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In an information acquisition system, the sensor is usually at the front of the system, the first of the detection and control systems. It provides the raw information necessary for system processing and decision making. Therefore, the accuracy of the sensor is critical to the overall system. In the measurement of displacement, velocity and acceleration, the differential transformer type sensor is often used because of its high sensitivity, good linearity and supporting integrated circuits, but the traditional LVDT sensor requires too much stability and accuracy for the working power supply, and Most of the circuit boards are made up of separate components, which are prone to looseness and moisture deterioration, which affects the service life and overall performance of the sensor. This paper introduces an LVDT linear displacement sensor based on AD598 signal processing chip, and discusses its error and precision by examples. 1 Basic principles A differential transformer type sensor is a device that realizes measurement by utilizing changes in the self-inductance or mutual inductance of a coil, and its core is a variable self-inductance or a variable mutual inductance. The variable air gap differential transformer type inductive sensor used in this paper uses the change of mutual inductance to work. 1.1 Basic structure and working principle There are one excitation coil and one output coil on the upper and lower iron cores. The upper and lower excitation coils are connected in series and then connected to the AC excitation power supply voltage Uin, and the two output coils are reversely connected in series according to the potential. Ignore the high-order infinitesimal quantity. When ωR(ω is the frequency of the AC excitation power supply voltage Uin and R is the equivalent resistance of the excitation coil), it can be derived. Where: Uin is the excitation power supply voltage (unit V); Uout is the output voltage (unit V); N1, N2 are the turns of the excitation coil and the output coil respectively; △ δ is the distance of the axis offset balance position (unit: mm) ; δ accounts for the air gap size (in mm) when the axis is in equilibrium. When the shaft is at the intermediate position, δ1 = δ2 = δ, and alternating magnetic fluxes φ1 and φ2 are generated in the exciting coil, and an alternating current induced potential is generated in the output coil. Since the air gaps on both sides are equal and the magnetic reluctance is equal, φ1=φ2, the potential E21=E22 induced in the output coil, since the secondary is connected in reverse by the potential, the output voltage Uout=0. When the axis deviates from the intermediate position, the air gaps on both sides are not equal (ie, δ1 ≠ δ2), and the potentials induced in the output coil are no longer equal (ie, E21 ≠ E22), and the voltage Uout is output. The size and phase of the Uout depends on the magnitude and direction of the displacement of the shaft. 1.2 Output characteristic equation The primary side excitation voltage of the differential transformer is Ep, the angular frequency is ω, the current is Ip, the inductance is Lp, and the equivalent resistance is Rp. The secondary voltages are E21 and E22, respectively, and the mutual inductance is M1 and M2. If you ignore the effects of hysteresis eddy currents and coupling capacitors, you can conclude that: 2 sensor measurement circuit AD598 is a new LVDT dedicated signal processing chip introduced by Analog Device. The schematic diagram is shown in Figure 2. As can be seen from the figure, the chip mainly consists of two parts: one part is a sine wave generator, its frequency and amplitude can be determined by a few external components; the other part is the signal processing part of the LVDT secondary. Through this part, a DC voltage signal proportional to the displacement of the core is generated. The AD598 can drive up to 24 V, LVDT primary windings in the frequency range of 20 Hz to 20 kHz, and accepts a minimum of 100 mV secondary input, making it suitable for many different types of LVDTs. 3 measurement system error analysis The error of the measurement system can be divided into two categories: fixed error and random error. 3.1 Fixed error Fixed error refers to the error caused by the structure of the differential transformer (machining accuracy) and the material (hysteresis eddy current). This is a comprehensive consideration of the accuracy requirements and economic indicators of the measurement in the system demonstration. Once the system is determined, these factors are generally not changeable. 3.2 Random error The random error can be divided into the error caused by the fluctuation of the excitation source and the error caused by the phase sensitive detection according to the error source. Because the AD598 encapsulates the oscillator, LVDT and phase sensitive demodulator, it not only improves the integration of the product, but also greatly reduces the number of external components, so that the performance of the sensor is greatly improved. Therefore, it is not correct in this paper. The error caused by phase sensitive detection is derived.

According to the James Consulting, researchers from the Belgian Microelectronics Research Center (IMEC) and the Dutch Applied Science Organization (TNO), the Holst Center researchers showed a test for detecting fingers. New flexible, large area sensor technology for palm prints. With a thickness of less than 0.2 mm and no large prisms or moving parts, the new sensor can be embedded in objects such as mobile phones and door handles to create an "invisible" but secure access control system that recognizes that the scanned object is alive rather than a phantom. Or a fake person. The technology paves the way for low-cost sensors for large-area finger and palmprint scanners, which will be on display at the Information Display Association (SID) 2018 Display Week Innovation Zone in Los Angeles, USA, and will be in Belgium. The IMEC Technology Forum (ITF) in Antwerp is on display. The two demonstration machines will demonstrate the technological potential for high resolution and large area effective detection areas. Among them, the 6 x 8 cm, 200-ppi demonstration machine is large enough for the 4-finger scanners currently used by border management and provides adequate image quality for basic identification applications. At the same time, the slightly smaller 500 ppi demonstration machine provides higher image quality, meets FBI standards, and is sufficient for law enforcement agencies to visualize details and pores for more powerful identification. Like the Holst Center's early flexible X-ray detectors, this fingerprint sensor combines an organic photodiode front panel, an oxide thin film transistor (TFT) backplane (originally developed for flexible displays) and a thin film barrier for protection. Together. All three technical elements have been or are being transferred to industrial production to expand and commercialize. The sensor reads hand fingerprints or palm prints by detecting visible light (400 to 700 nanometers) reflected from the skin surface. Moreover, they can also detect part of the light that penetrates the skin before reflection. This allows them to perceive the heartbeat from changes in the capillaries of the hand, thereby verifying that the scan mark is from a living person. In addition, by using different photodiode materials, the sensor's functionality can be extended to other wavelengths, such as near-infrared (NIR). This technology will enable new authentication modes, such as identification by hand vein pattern, which is even more specific to individuals than fingerprints. Near-infrared sensors can also be used for other purposes such as blood oxygen monitoring, night vision and 3D facial recognition. Holz Center project manager Hylke Akkerman said: "The flexible fingerprint sensor demonstration machine demonstrates the versatility and maturity of the flexible electronics technology being developed by Holst Center. Since the underlying technology has been applied to the flat panel industry, it is the new flexibility. The manufacture of fingerprint sensors has established a fast track, and we are looking for industry partners to take this step.

To make modern direct injection (DI) combustion engines meet strict emission regulations, higher levels of exhaust aftertreatment are an indispensable and important condition: converting nitrogen oxides (NOx) into harmless substances and from the exhaust stream. Filtering out gasoline and diesel particulate matter (PM) is a core function of the car. Continental has recently introduced advanced sensor solutions designed to further enhance control, enabling exhaust aftertreatment to meet vehicle emission standards in China and around the world. The post-processing system is equipped with Continental's intelligent high temperature sensor (HTS) and differential pressure sensor (DPS) for fast response and high precision measurement. At present, intelligent high temperature sensors are now in the second generation, helping customers save system cost and manpower. Mr. Fan Mingxiang, Sales Director of Continental's Sensors and Actuators business unit in China, said: [From a global perspective, the post-processing market is a promising market, and we have seen China's particularly strong demand. To meet these needs, Continental continues to We are developing new technologies to reduce emissions. We are proud to be able to deliver our second generation of high temperature sensors and differential pressure sensors to the Chinese market to help our customers meet emission standards reliably and efficiently." Intelligent High Temperature Sensors (HTS) The currently established diesel exhaust cleaning method requires a diesel particulate filter (DPF), a diesel oxidation catalyst (DOC), and a selective catalytic reduction (SCR) unit for the conversion of nitrogen oxides. Complex post-processing will be monitored throughout to ensure the highest conversion efficiency and filtration efficiency are maintained at all times. The use of a gasoline particulate filter (GPF) is also advantageous for direct injection gasoline engines. The sensor provides critical data for emissions control. Continental's intelligent high temperature sensors detect temperature in the exhaust system from different locations. Since the aftertreatment system can only work at the right temperature level, it is important to confirm the temperature. To ensure optimal emissions control, temperature collection needs to be fast and accurate. Continental's second generation of high temperature sensors are tailored to meet these goals. It is based on thermocouple technology that converts temperature into an accurate digital signal and forwards it to the engine control unit (ECU) for optimal catalytic conversion and on-board diagnostics. In addition to providing critical data, high temperature sensors simplify system layout with multiple sensor probes for close monitoring. In addition, high temperature sensors can be used to provide overheat protection for critical components such as turbochargers. Continental's second-generation high-temperature sensor has been in production in Changchun, China since 2016. Differential Pressure Sensor (DPS) Gasoline Direct Injection (GDI) engines have good fuel economy and can effectively reduce carbon dioxide emissions. However, the quality and quantity of particulate matter (PM) emitted by gasoline direct injection engines is significantly higher than that of valve-type fuel injection gasoline engines. The function of the gasoline particulate filter and the differential pressure sensor is to remove particulate matter or soot from the exhaust gas of the gasoline/diesel engine. Continental's particulate filter differential pressure sensor (PFD) can be used to infer the flow of exhaust gas through a gasoline/diesel particulate filter using the differential pressure in the measuring filter. This technology will provide an analog or digital output voltage proportional to the differential pressure across the filter. At a predetermined pressure increment, the engine control unit initiates a regeneration process to remove particulate matter accumulated in the filter and restore exhaust gas flow. Mr. Fan Mingxiang added: [The sensor and actuator team of Continental Group has strong strength in the production and R&D of these two products. I believe that the local team will be dedicated to providing complementary services to local customers."

Circuit diagram of automatic transmission control unit, solenoid valve, vehicle speed sensor, transmission oil temperature sensor

Today, manufacturers of plastic processing equipment use a low-cost linear linear potentiometer for displacement measurement and control, but this equipment will experience severe wear and tear after a long period of use, resulting in linear deviation, causing users The consequence is that it costs a lot of money to repair and suffer serious losses from production stoppages. Balluff's engineers have developed the Micropulse-AT linear displacement measurement control system that is optimized for cost savings. The new Balluff Micropulse-BTL 5 unit has a rounded housing. The resolution of this displacement sensor is ≤10mm, and the repeating positioning accuracy is ≤20mm when the measuring range is 50-1500mm. The Micropulse-AT unit with IP67 enclosure rating is placed in an anodized aluminum hermetic housing. In this way, the system can be protected against dust, water and vibration and shock. This rounded housing and its many advantages provide ease and flexibility for installation. It can be attached to any part of the machine. As long as the vertical distance between the positioning magnet and the sensor does not exceed 8 mm, the possibility of damage to the displacement measuring system due to lateral force and signal interruption can be eliminated. The magnet can be placed with a vertical deviation of ±5 mm. Balluff displacement sensors can be fixedly mounted using standard components commonly used on the market. Because the displacement sensor has large mounting tolerances, no time-consuming structural modifications and fine adjustments are required. The Micropulse-AT unit with two positional magnet position sensors is particularly cost effective and can measure two axial movements with one measurement system without additional investment. Use an M12 plug cable for electrical connections. The Micropulse-AT unit operates at 24V with a 10V analog output or a P110 digital pulse interface for uninterrupted data transfer. It can match all the common processing cards of Balluff and the control devices of various manufacturers, and can transmit 500m signals safely. Companies using their own control and signal processing devices can also achieve high-resolution pulse interface analysis results. Balluff's Micropulse-BTL 5 sensor can be used as a bus system. For example, the Profibus DP system is available in a multi-plug version without a dispenser. In this case the busbar wires are separated from the supply voltage. With Profibus and Canopen systems, up to 4 positions of velocity data and diagnostic data can be transmitted to the control unit with a resolution of 5 mm and a speed of 0.1 mm/s. In addition, in cooperation with Wago, the Balluff Micropulse-BTL 5 unit can be connected to all busbar systems commonly found on the market. This connection is achieved by a 750 series terminal with an integral ASIC device for the pulse interface and a corresponding bus coupler. There is also a Micropulse-AT device with a digital pulse interface/integrated protocol (DPI/IP) pulse interface, a protocol for direct data exchange between the control unit and the displacement sensor. The benefits of this protocol are: simple automatic parameterization, identifiable damaged or replaced measurement systems and improved machine safety.

Abstract: This paper designs a somatosensory interactive control system for the Meinham wheel omnidirectional walking transport platform. The system uses kinect sensor to propose two kinds of control methods: bone motion information recognition and depth gesture recognition based on different scenes. Based on the skeletal motion information recognition control method, the human body depth image data is acquired by kinect, then the bone tracking technology is used to extract the joint points of the human body, and the spatial coordinate system is established. Finally, the vector joint calculation method is used to calculate the rotation angle of the human body to realize the dynamic motion recognition. Convert to control instructions for platform control. Based on the depth gesture recognition control method, the depth information acquired by the kinect is used to realize the hand segmentation from the background, and then the template matching method is used to recognize the gesture conversion into the control command to realize the platform control. Experiments show that the control system can effectively and flexibly control the all-round transportation platform. This article refers to the address: http:// With the advancement of technology, people have been working on the research of convenient and efficient transportation institutions. The omni-directional motion mechanism achieves a high degree of flexibility in a small space with its full freedom of movement in the plane, and has broad application prospects in many aspects such as military, industrial, and social life. Human-computer interaction with human posture and gestures is a novel and natural way of interaction. People can perform rapid human-computer interaction through simple body language, which is easy to implement and flexible. Kinect is a somatosensory recognition device developed by Microsoft Corporation, which can realize somatosensory recognition and human-computer interaction. Therefore, this paper designs a model of somatosensory control omnidirectional transportation platform using Mecanum wheel. For this model control system, two kinds of somatosensory control modes based on kinect sensor-based bone motion information recognition and deep gesture recognition are proposed. The two scenarios applied to the transport platform: when the platform is integrated into remote devices such as mobile robots, The operator has a wide control environment and can apply various postures of the human body for fine control. When the transportation platform is integrated into a short-range control device such as a wheelchair or a forklift, the operator is located on a narrow device, and the short-distance gesture can be applied for simple, fast and efficient operation. Manipulation. The experimental results show that the two control modes of the control system can well control the omnidirectional transportation platform. 1 Model construction and kinematics analysis of omnidirectional transportation platform 1.1 omnidirectional platform construction The omni-directional mobile platform constructed in this paper is shown in Figure 1(a). It consists of aluminum 60mm 45 degree universal wheel, DC motor, motor drive module, 12V lithium battery, MSP430f149 minimum system control board, serial Bluetooth and other components. constitute. The platform controller reads the data sent by the host computer through the Bluetooth to perform the corresponding action correspondingly, and FIG. 1(b) is the model object. 1.2 Omni-directional kinematics analysis and manipulation As shown in Fig. 2(a), the principle structure of the Mecanum wheel is such that a small roller with α=45 degrees to the axis of the wheel is distributed around the main wheel. The roller can rotate itself while rotating around the axle, so that the main wheel has two degrees of freedom of rotation about the axle and movement in the direction perpendicular to the axis of the roller. Figure 2 (b) shows the chassis motion mechanics analysis. The kinematics equation of the platform is obtained by analyzing the motion of the wheel: In the formula, (1) Vx, Vy, and ω are control quantities. In this paper, the PWM drive signal Cn is generated by the single-chip microcomputer to realize the chassis drive control. From equation (2), Cn is the power of the nth motor, ωn is the calculated speed of the nth motor, ωmax is the speed at the maximum output power set by the n motor at the same voltage, mn is the maintenance 4 The measured parameters of the motor speed at the same maximum. 2 Human body depth image and bone information acquisition The kinect sensor is used to obtain the depth image and bone information of the human body. It is composed of modules such as RGB color camera, infrared emitter, and infrared CMOS camera, and can obtain depth image data and RGB image data of the target object. Based on the depth image data, bone tracking technology is used to extract human bone information. 3 skeletal motion information recognition control mode design 3.1 joint angle calculation method Kinect can track 20 bone points in the human limbs. The bone movement information recognition control mode refers to the system identifying the control commands by analyzing the motion data of the human skeleton points. In this paper, the left and right shoulder joint points, the left and right elbow joint points, the left and right wrist joint points, and the left and right hand joint points are used to identify the movement of the joints by recognizing the rotation angle of each joint. In this paper, the human skeleton data obtained by kinect is used to establish the spatial coordinate system with the center of the shoulder as the origin. The vector is calculated according to the coordinate construction vector of each joint point, and the joint rotation angle is obtained. The specific calculation of the rotation of the right elbow joint is taken as an example. As shown in Fig. 3, a, b, and c are respectively the shoulder joint point, the elbow joint point, and the wrist joint point of the right hand, and the corresponding space coordinates are (x1, y1, z1), (x2, y2, z2), respectively. (x3, y3, z3), the angle of movement of the elbow joint is α. Then there is Finally, the angle of motion of the joint can be obtained by inversely solving the trigonometric function. 3.2 Motion posture corresponding control command So this article uses two-handed cooperation to control the operation of the omnidirectional chassis. From the mathematical model, we can get the omnidirectional moving chassis with arbitrary trajectory movement ability, but because of the directionality of the motion trajectory, it is easy to lead to control instability, but the advantage becomes a disadvantage. From this we have streamlined the directionality of the movement so that it satisfies both the rich motility of the omnidirectional movement and the stability. See the table here. We set up 10 kinds of direction movements and split the different natural gestures corresponding to the control commands. 4 gesture recognition mode design 4.1 Background segmentation In the gesture recognition based on the image data, it is necessary to extract the gesture of the operator. First, we need to separate the palm portion of the character from the background information. Based on the depth data extracted by kinect, this paper uses the threshold segmentation method to perform background segmentation, which is to extract the average depth value of the foreground and segment the scene. The formula for setting the depth threshold is: Maxmax=ω+ε (6) Among them, ω is the minimum value of the palm of the hand that can be accurately divided by the experimental measurement, ε is the adjustable value that can be freely set according to the actual application scene, and μmax is the distance space that can accurately identify the palm. 4.2 Gesture recognition In this paper, a template matching algorithm proposed by Y-H.Lin is used to process the extracted gestures and perform gesture recognition. The algorithm first converts the extracted two-dimensional image into a one-dimensional vector, which eliminates the influence of in-plane graphics scaling and rotation. At the same time, a plurality of scale reference template vectors are constructed for the same gesture, and the extracted gesture vectors are compared with the reference template to obtain a comparison result. 4.3 System Flow Chart The flow chart of the system using gesture recognition for control is shown in Figure 4. 4.4 Gesture corresponding instructions For the application scenario of the current control mode, this paper designs 6 motion instructions for the transportation platform to meet the simple and accurate control requirements of the operator process. The specific gesture corresponding instructions are shown in Figure 5. 5 Experimental analysis The Kinect development tool used in the control system host computer is Kinect Software Devel-opment Kit (SDK) v1.8, the development environment is Visual Studio 2013, and the programming language used is C#. 5.1 skeletal motion information recognition control mode validity test The success of this mode of application lies in the effectiveness of the identification of the angle of rotation of the joint points of the application. Based on this, we performed a rotational angle recognition test on the joint joints of the left and right shoulder joints, elbow joints and wrist joints. The specific test method is as follows: We select 10 people whose body height is different, and the rotation angle of each joint is set to 10°, 20°, 40°, 60°, 80°, 5 cases in each case. That is, each joint is accumulated for 250 experiments, and the angle is allowed to be ±30°. Experimental results of removing accidental abnormal results are shown in Table 4. From the table, the following findings can be found: the recognition rates of the three nodes from the left and right shoulder joints to the left and right wrist joints are sequentially reduced; the greater the rotation angle, the higher the success rate of recognition. The reason for the above phenomenon is that the kinect recognizes that the angle of the human joint is related to the change range of the human body posture, and the amplitude of the human body posture of each joint point of the human body depends on the joint point as the position and the rotation angle of the joint point, so the shoulder joint has the highest recognition accuracy. The greater the angle of rotation of the same joint point, the higher the recognition rate. Despite this, the recognition rate of each joint at each rotation angle exceeds 90%, which has a high recognition success rate and meets the control requirements. 5.2 Gesture Recognition Test For the proposed control gestures, we launched the recognition accuracy test. The specific test method was that we selected 10 people who did not use the hand to perform 10 recognition tests for each gesture, that is, 50 times for each gesture test. As shown in the table, we can find that because the gestures we use are relatively large and the number of gesture categories is small, the gesture recognition accuracy is high and meets the control requirements. 5.3 Overall Maneuverability Verification After verifying the effectiveness of the two somatosensory control modes, in order to actually test the handling performance of the transport platform, we used black tape to lay out a scene for performing tasks on the flat ground, inviting three simple trained operators to control. The test was controlled three times using two modes, and the experiment showed that all of the three people completed all the test content, but the time and route were inconsistent, the skilled operator route was smoother than the unskilled operator, and the time was short. At the same time, limb manipulation is more time-consuming than gesture manipulation because it is more elaborate than gesture control. 6 Conclusion In this paper, two kinds of somatosensory control modes based on kinect-based bone motion information recognition and deep gesture recognition are proposed for a omni-directional transport platform based on Mecanum wheel. It is proved by experiments that both control modes can meet the control requirements and have flexibility. And high efficiency.

An encoder is a device that compiles and converts a signal (such as a bit stream) or data into a signal form that can be used for communication, transmission and storage. According to its working principle, it is divided into two categories: incremental and absolute. There are three main differences, as follows: 1.Different principles The incremental encoder converts the displacement into a periodic electric signal, and then converts this electric signal into a counting pulse, and the number of pulses is used to indicate the magnitude of the displacement. There are many engraved lines on the code disc of the absolute encoder to arrange each position on the encoder. Since each position is different, if you want to know the magnitude of the displacement, you only need to know the starting position and the ending position, and you don`t need to keep counting like an incremental encoder. To describe it as pouring water, an incremental encoder is like finding a cup of unknown size and pour water into it. When it is full, empty the cup once, then pour water, and finally calculate the distance based on the number of times the cup is filled. An absolute encoder is like finding a taller cup with a scale, pour water into it, and finally calculate the distance based on the start and end scale. There is a problem. What to do if the cup is full? The solution is to find a larger cup with graduations, pour the water in the small cup into the large cup, and finally add up to calculate the distance. This is a single-turn absolute encoder and a multi-turn absolute encoder. 2. Different memory for power on and off Incremental encoders have no memory. Power off and restart must return to the reference zero position in order to find the desired position, and restart each time the power is turned on. The most common incremental encoder is the positioning of the printer scanner. Every time the printer is turned on, we can hear a crackling noise. In fact, this is the printer looking for the reference zero point, and it can only work after this. The absolute encoder has a memory, and the target position can be known without returning to the zero position after power off and restart. This prevents the absolute encoder from being disturbed in the process, and its anti-interference characteristics and data reliability are greatly improved. 3. Different application areas The presence or absence of breakpoint memory makes incremental encoders and absolute encoders very different in the field of use. Incremental encoders are more suitable for determining speed, distance or direction of motion, while absolute encoders are Features are more and more widely used in the field of industrial control positioning.

The working principle of the linear displacement sensor is the same as that of the sliding varistor. It is used as a voltage divider and it shows the actual position of the measured position with relative output voltage. There are the following requirements for the operation of this device: First, if the electronic ruler has been used for a long time, and the seal has been aged, mixed with a lot of impurities, and the water mixture and oil will seriously affect the brush's contact resistance, so that the displayed figures will constantly jump. At this time, it can be said that the electronic scale of the linear displacement sensor has been damaged and needs to be replaced. Second, if the capacity of the power supply is very small, there will be many situations. Therefore, the power supply needs sufficient capacity. Then, if the capacity is insufficient, the following situation will occur: the movement of the melted plastic will cause the display of the molded electronic ruler to change, and there will be fluctuations, or the movement of the mold clamping will fluctuate the display of the ejected electronic ruler, resulting in a great error in the measurement result. If the drive power of the solenoid valve is at the same time when the power supply of the linear displacement sensor is at the same time, the above situation is more likely to occur. When the situation is serious, the voltage of the multimeter can even measure the fluctuation of the voltage. If the situation is not due to high-frequency interference, static interference, or neutrality is not good enough, then it may be caused by the power of the power supply is too small. Third, FM interference and static interference may cause digital displacement of the digital scale of the linear displacement sensor. The signal line of the electronic ruler should be separated from the strong electrical line of the device. The electronic ruler must use the grounding bracket forcibly. At the same time, the electronic ruler's housing should be in good contact with the ground. The signal line needs to use shielded wire, and a section of the box should be grounded with the shielded wire. If there is high-frequency interference, usually using a multimeter's voltage measurement will show normal, but the display number will be beating constantly; and in the case of static interference, the same situation occurs with high-frequency interference. To prove whether it is an electrostatic disturbance, you can use a power cord to short-circuit the electronic ruler's capping screw to some metal on the machine. As long as it is shorted, the electrostatic interference will be eliminated immediately. of. But if you want to eliminate high-frequency interference it is difficult to use the above method, Frequency Inverters and robots often appear high-frequency interference, so you can try to use the method to stop the high-frequency power saver or robot to verify that it is not high Frequency interference. 4. If the electronic scale of the linear displacement sensor is in the course of working, if the displayed data at a certain point regularly jumps or no data is displayed, it is necessary to check if the insulation of the connecting wire is damaged. , and short circuit to ground caused by regular contact with the outer shell of the machine. Fifth, the power supply voltage must be stable, industrial voltage needs to meet the stability of ± 0.1 [%], for example, the reference voltage is 10V, you can allow fluctuations of ± 0.01V, if not, it will cause display The traps fluctuate in such situations. However, if the amplitude of the display fluctuation at this time does not exceed the fluctuation amplitude of the fluctuation voltage, then the electronic scale is normal. 6. The alignment of the linear displacement sensor needs to be very good, but the parallelism can tolerate an error of ±0.5mm, and the angle can tolerate an error of ±12°. However, if the parallelism error and the angle error are both too large, this will cause the display of digital jitter. When such a situation arises, it is necessary to adjust the degree of parallelism and angle. 7. During the process of connection, we must pay more attention to the fact that the three lines of the electronic ruler cannot be connected wrongly. The power lines and output lines cannot be exchanged. If the above line is connected wrongly, there will be a large linear error, it is difficult to control, the control accuracy will become very poor, and the display is prone to beating and so on.

Abstract : Entering a new era, the development of electronic technology has become the main factor affecting the development direction of automobiles. Sensors are the core components of electronic technology and have been widely used by modern automobiles. One of its functions is to improve the brake handling performance of the chassis, the stability of the steering performance and the safety of the car. This paper deeply studies the application status of sensors in the electronic control of automobile chassis, and gives a detailed introduction to its future development trend. This article refers to the address: http:// 1 Introduction With the development of electronic technology, the degree of electronicization of automobiles is also increasing. The connection between the device and the actuator of the chassis control system also enters the electrical signal connection phase by a simple mechanical connection phase. A good chassis electronic control system improves the adhesion between the wheel and the ground, thereby improving the safety, power and comfort of the car [1]. The application of electronic control systems in automotive chassis technology has improved the active safety of automobiles. Common chassis control systems are as follows: traction control, brake control, suspension control and steering control [2]. The sensor is the core device in the electronic technology. It is a device for signal transformation. Its function is to transform the measured non-electricity signal into a power signal, which is a key device to promote the comprehensive development of automotive technology. In the electronic control system of the car chassis, the control work is inseparable from the sensor [3]. Sensors for chassis control refer to sensors distributed in the transmission control system, power steering system, suspension control system, braking system, etc. They function differently in different systems, but their working principle is the same [4 ]. 2 Theoretical basis of electronic control of automobile chassis The main function of the car chassis is to allow the car to move according to the driver's wishes, such as acceleration, deceleration and steering. The driver expresses his or her wishes by manipulating the steering wheel, throttle and brake pedal in the car. The amount of execution corresponding to these controls is the steering angle of the front wheels and the driving or braking torque on the wheels. What works is the longitudinal and lateral forces of the tire. The main factors affecting the tire force of the car are the adhesion coefficient of the road surface, the normal force of the wheel, the wheel slip rate and the wheel side yaw angle. The basic principle of the car chassis control design is to properly adjust and control the wheel slip rate and the wheel side declination under the premise of the road surface adhesion coefficient and the wheel normal force, thereby indirectly controlling the longitudinal force and side of the tire. For the purpose of force, to maximize the use of adhesion between the tire and the road surface, to achieve the purpose of improving the car's active safety, mobility and comfort. The electronic control of the car chassis is a complex system engineering that interacts and interacts with multiple systems. The specific performance is as follows: (1) The same control system may have multiple actuators and control multiple variables simultaneously. (2) The same control target can be controlled by different control systems or by multiple systems. (3) The same control target is simultaneously controlled by different control systems. (4) Different control systems may share the same sensor or control unit [2]. 3 Application status of sensors in electronic control of automobile chassis 3. 1 sensor application in power steering system In the power steering system, the control object of the sensor is the steering angle of the wheel, and the electronic steering control of the steering angle of the wheel achieves the purpose of controlling the power steering system. Common power steering systems are: active front wheel superimposed steering system AFS, active front wheel power steering system ESP and active rear wheel steering system RWS. The sensors used mainly include an engine speed sensor, a vehicle speed sensor, a torque sensor, etc., and the power steering electronic control system increases the output power and reduces the engine loss while achieving a light steering function and improved response characteristics. It also saves fuel. The working principle of all power steering systems ESP, AFS and RWS is commanded by the driver. The sensor senses the condition of the road surface and transmits the road surface condition to the electronic controller and actuator through the network in the form of electrical signals. For example, in the EPS system, the microcomputer-controlled steering assist system has the characteristics of small components, small mass, and small size. When the system works, if we choose the best transmission ratio, we can get the fastest response: when the car is driving at high speed, the steering speed ratio will become smaller, and the steering force will gradually increase, which will make the car direction more. Stable and safer to drive. When driving at a very low driving speed, the steering speed ratio will become larger. At this time, the steering wheel is only slightly lightly angled, and the body displacement will change greatly, which makes a lot of work easier, such as Parking is in place; the system is characterized by improved steering and steering response, as well as increased stability at high speeds and maneuverability at low speeds. In addition, since the EPS can apply an extra torque to the steering wheel as needed, the driver can turn the steering according to the prompt signal of this torque, which is the function suggested by the steering of the system. The system mainly consists of an electronic controller, an electric motor and a motion transmission mechanism, a motor speed sensor, a steering torque sensor and a steering wheel angle sensor. Other systems, like the EPS system, each play an irreplaceable and important function. 3.2 Application of Sensor in Suspension System Control The operation of the sensor in the suspension system control is to intervene and adjust the characteristics of the vehicle suspension components, so as to achieve the purpose of vehicle dynamics control. When working, the system integrates the motion state of the car and the information detected by these sensors, and calculates the optimal damping coefficient of each wheel suspension damper, and then makes work orders such as automatically adjusting the vehicle height and suppressing the change of the vehicle posture. Thereby control of steering stability, driving stability and vehicle comfort is achieved. The continuous damping control system ADC consists of four control units, CAN, four wheel vertical acceleration sensors, four body vertical acceleration sensors and four damper proportional valves. 3. 3 Application of sensor in electronic control system for driving and braking 3. 3. 1 The sensor is used in the traction control system TCS. Since the driving torque of the driving wheel of the automobile is too large, the driving wheel will slide relative to the ground. According to the calculation, the safe slip rate of the drive wheel should not exceed 20%. Therefore, we need to control the drive wheel slip rate. The system that controls the drive wheel slip rate is the traction control system TCS. It is developed on the basis of ABS. In most cars, TCS and ABS share an ECU. The job of the sensor is to sense the slip of the car, and then input the obtained information into the system as an electrical signal. The system analyzes the signal input by the sensor to identify and judge the driving condition of the car, and accordingly takes corresponding measures. 3. 3. 2 The application of the sensor in the automotive dynamics electronic stability system ESP. The ESP system is an active safety system that enables the car to have more comfortable maneuverability and better direction stability. The basic working principle is to identify the driver's desired motion state by analyzing the sensor input signal and performing logical operations. The actual movement state of the car is known by adjusting the longitudinal force of the wheel and the driver's expectation of the car. Therefore it requires more sensors than the ABS and TCS to control the yaw motion of the car. This type of sensor identifies the driver's expectations for the car, including the steering wheel sensor, the lateral acceleration sensor, the car yaw rate sensor, and the hydraulic sensor of the brake master cylinder [4]. 3. 3. 3 The application of the sensor in the vehicle anti-lock braking system ABS. Anti-lock braking system ABS is an important safety component in automotive electronic devices with the longest development time and the fastest application. Its working principle is: control to prevent the wheel from locking when the car brakes, and to ensure the best sliding rate between the wheel and the ground (5%-20%). In this way, no matter what kind of road is braked on the road, the vertical peak adhesion coefficient and the large lateral adhesion coefficient can be achieved between the wheel and the ground, so that the vehicle can be braked without braking. Loss of steering conditions and other unsafe conditions, reducing the braking distance, improving the handling stability and safety of the car. The functioning sensor is an anti-lock brake sensor. It mainly detects the wheel speed by using the wheel angular velocity sensor, and controls the brake oil pressure when the slip ratio of each wheel is 20%, thereby improving the braking performance. Ensure the purpose of vehicle handling and stability [5]. Among them, the wheel speed sensor is a very important device of ABS. Its main job is to provide reliable and accurate wheel speed to the ECU in time. If there is no wheel speed sensor, the work of the system can not be completed, and the accuracy of the wheel speed sensor will directly affect the work of the system. The wheel speed sensor is mainly There are several types of electromagnetic, Hall, and magnetoresistive. 4 Development trend of sensors in electronic control of automobile chassis With the development of electronic technology and the automotive industry, the development of automotive sensors will become one of the key factors affecting the development of high-end, electronic and automation of automobiles. The higher the degree of automation of the car, the greater the dependence on the sensor. Therefore, many automotive electronics industries regard the vehicle sensor technology as a key research and development technology project. Since the electronic control system of the car chassis is composed of many systems, the types and quantities of sensors required are also various. Therefore, it is necessary and necessary to develop new sensors with high precision, high reliability and low cost. In order to meet this need, the development trend of the sensor of the electronic control system of the automobile chassis in the future will definitely be toward the direction of integration, intelligence and miniaturization; on the basis of basic research, discover new phenomena, adopt new principles, and develop new ones. Materials and the adoption of new processes [7]. The sensor is becoming more and more accurate, and the technology content is getting higher and higher, so as to better promote the development of electronic technology and even the automotive industry. 4.1 Introduction to development trends The intelligent sensor is a sensor with a microcomputer and various functions such as detection, judgment, and information processing. Compared with traditional sensors, it can correct the measurement data by determining the working state of the sensor, thus reducing environmental factors such as temperature. Its greatest advantage lies in its ability to fully understand the driver's and passenger's condition, traffic facilities and surrounding environment information; to determine whether the driver and passengers are in the best condition, whether the vehicle and people will be in danger, and take appropriate measures in a timely manner. The difference is that it uses software to solve problems, which are difficult to solve in ordinary sensors. For example, the calculation and processing of data are completed, and the intelligent sensor not only has large range coverage, large output signal, high precision, high signal-to-noise ratio, good anti-interference performance, and many self-test functions [7] . In the future, if this sensor can be applied to the electronic control system of the car chassis, it will bring a lot of convenience to the driver. The versatile integrated sensor is a sensor that integrates multiple functionally sensitive components and multiple sensitive components of the same function. This sensor can detect two or more characteristic parameters or chemical parameters, which reduces the number of chassis sensors and improves the accuracy of its electronic control system. Micro-sensors use micromachining technology to package micron-sized sensitive components, signal processors, data processing devices, etc. on a single chip. This sensor is easy to integrate, small in size, and inexpensive, and small and sophisticated components can be clearly Improve system test accuracy. At present, this technology has gradually matured, and it is possible to produce various miniature sensors such as mechanical quantity, magnetic quantity, and thermal quantity. This sensor is used in the electronic control system of the car chassis and will greatly optimize many of the car's performance. 4.2 Research methods and directions The research and development of sensors is the inevitable development of electronic technology. The basic principles of various sensors are the same, that is, the use of physical phenomena, chemical reactions and biological effects. Therefore, discovering new phenomena and new effects is an important basis for the development of modern sensors. Another important basis for the development of sensor technology is functional materials. Due to the rapid development of materials science, material manufacturing has reached a very high level, that is, we can arbitrarily control the composition of materials when manufacturing various materials. In view of this, we can also design and manufacture a variety of functional materials for sensors. For example, by adding different semiconductor oxides, gas sensors of various properties can be manufactured; optical fibers can be used as materials for sensors, which is a major discovery of sensor functional materials; in addition, many experts in automotive electronics at home and abroad also There has been a strong interest in organic materials, and they are speculating whether organic materials can be used as functional materials in sensors, which remains to be further studied by experts. For a sensor, the performance of its sensitive components is highly dependent on the functional materials used. However, the processing also has a certain impact on the performance of the component. Therefore, improving the processing technology will also be a direction for future research. As various new materials such as semiconductors, ceramics, etc. are applied to sensor sensitive components, many modern advanced processing technologies are gradually introduced into automotive sensor manufacturing processes, such as ion implantation technology, integration technology, and micro-machining technology. By using these new technologies, it is possible to manufacture new sensitive components with high reliability, small size, light weight and stable performance. For example, due to the rapid development of technology, microelectromechanical systems (MEMS) technology has matured, and this technology has evolved from semiconductor integrated circuit technology. Micro-electromechanical systems can be used to create a variety of miniature sensors capable of sensitively detecting mechanical, magnetic, thermal, chemical and biomass [8]. For a sensor, the performance of its sensitive components is highly dependent on the functional materials used. However, the processing also has a certain impact on the performance of the component. Therefore, improving the processing technology will also be a direction for future research. As various new materials such as semiconductors, ceramics, etc. are applied to sensor sensitive components, many modern advanced processing technologies are gradually introduced into automotive sensor manufacturing processes, such as ion implantation technology, integration technology, and micro-machining technology. By using these new technologies, it is possible to manufacture new sensitive components with high reliability, small size, light weight and stable performance. For example, due to the rapid development of technology, microelectromechanical systems (MEMS) technology has matured, and this technology has evolved from semiconductor integrated circuit technology. Micro-electromechanical systems can be used to create a variety of miniature sensors capable of sensitively detecting mechanical, magnetic, thermal, chemical and biomass [8]. 5 Conclusion The wide application of electronic technology in automotive technology makes the control system of automobile chassis develop rapidly in the direction of electronic and intelligent, which leads to the emergence of many electronic control systems for automobile chassis, and the sensor is the core device of electronic technology. More and more sensors are used in the chassis of the car, and the brake handling performance, steering performance and safety performance of the vehicle are greatly improved due to the use of the sensor. At the same time, it also improves the economy and safety of the car. The effects of various electronic steering control systems such as AFS, EPS and RWS are even more pronounced. They can make reasonable recommendations to the driver when necessary or make necessary corrections to the driver's instructions. With the further development and improvement of electronic sensor technology, by integrating these new information with the electronic control system of the car chassis, more new functions and new systems will emerge, thus providing sufficient conditions for the development of the automotive industry. basis.

The normal operation of the temperature sensor element is to meet its operating conditions, one of which is its operating current, because the temperature sensor has a resistance value, when the current flows through the temperature sensor element, there will be power loss, it will heat, so in order to To reduce the temperature error caused by the sensor's own heating, so to meet the normal working conditions of the sensor, to minimize its own heat. This is why the temperature sensor is used under constant, low current conditions. So, for example, the platinum thermal resistance's normal operating current is 5mA, but our recommended operating current is 1MA. The reason is to reduce the measurement error due to self-heating of the temperature sensor element. The current is constant and its output has a linear relationship between temperature and potential. The insertion depth of the temperature sensor is also a problem that is easy to overlook. Some customers require a very short insertion depth but a relatively large diameter. This is unreasonable, especially in the case of high temperatures, which is not desirable. In theory, the temperature sensor is inserted. Depth can generally be determined according to actual needs. However, the minimum insertion depth should not be less than 8-10 times the diameter of the temperature sensor protection sleeve. In order to ensure stable performance of the temperature sensor. For example, the location and insertion depth of the thermocouple can not reflect the true temperature of the furnace, in other words, the thermocouple should not be installed too close to the door and the heating place, the depth of insertion should be at least 8 to 10 times the diameter of the protection tube; The gap between the protective sleeve of the thermocouple and the wall is not filled with heat insulation material, so that the heat in the furnace overflows or the cold air invades. Therefore, the gap between the thermocouple protection tube and the wall hole of the thermocouple is blocked with heat insulating material such as fireproof mud or asbestos rope to avoid cold and heat. Convection of air affects the accuracy of temperature measurement; the thermocouple cold junction is too close to the furnace body to make the temperature exceed 100°C; thermocouples should be installed as far as possible to avoid strong magnetic fields and strong electric fields, so thermocouples and power cables should not be installed in the Within the same conduit to avoid introducing interference caused by errors; thermocouple can not be installed in the area where the measured medium rarely flows. When using a thermocouple to measure the temperature of the gas in the tube, the thermocouple must be installed against the flow velocity and fully in contact with the gas. . Knowing the operating current and insertion depth of the temperature sensor is necessary for us to select and use the temperature sensor. If you ignore these two details, it is easy to cause unstable or even damaged temperature sensor performance.

Abstract: Solar LED lighting system has been widely used as a green energy source in recent years. It introduces a solar energy landscape lighting control system based on sensor network, which is simple, reliable and easy to deploy. Based on ZigBee wireless sensor network architecture, the light intensity of the lighting unit in the system is realized. Color control, using polling mechanism to solve the real-time acquisition of each lighting unit state and broadcast frame synchronization collaborative lighting unit to complete the scene conversion, all system information is processed centrally by the host computer control software through the GPRS network. Compared with traditional illumination sources, LED lamps have the advantages of low power consumption, long life, fast response, no radiation, high-frequency switch flashing, convenient dimming, etc., and are one of the important choices for landscape lighting. At present, solar LED landscape lighting systems are increasingly used in urban squares, main parks and other fields. The wireless sensor network square landscape lighting system introduced in this paper realizes the remote control of LED light switch, light intensity and color, and can flexibly construct multiple landscape scenes, and simultaneously detect the working status and power supply of LED lamps in real time to ensure timely and effective system maintenance. . 1 system structure The landscape lighting system is mainly composed of three parts: lighting unit, scene controller and monitoring host, as shown in Figure 1. The landscape lighting system staff realizes the detection, management and control of the working status of each lighting unit of the entire landscape system through the monitoring host. A monitoring host is set up in the system. The host computer is a computer connected to the Intenet and installed the landscape lighting system monitoring software. . The scene controller and the lighting unit it controls are the basic building blocks of the system. The monitoring host maintains information interaction with the system through the Internet and the GPRS wireless network. The number of scene controllers is determined according to the landscape lighting scale and the application environment, and each scene controller controls 1 to 127 lighting units to operate. Because landscape lighting has lower real-time requirements than industrial control systems and requires less information to be transmitted, the landscape system local communication uses ZigBee wireless sensor network (WSN), the lighting unit completes the WSN sensor network device function, and the scene controller The wireless sensor gateway function is implemented and acts as a co-ordinator of the respective sensor network, which is responsible for the networking and data transfer management of each sensor device. In addition to the completion of the sensor device function, the lighting unit in the system needs to complete the work of collecting the detection data of the lighting unit, sending data according to the system requirements, battery charging management, lighting control, and the like. Figure 1 Landscape lighting system composition 2 functional design 2.1 Lighting unit The main components of the lighting unit include a solar panel (group), a power management module, a battery (group), an LED light control module, and a wireless transceiver module. The solar panels (groups) convert the light energy into a current and charge the battery (group) via the power management module. After the landscape lighting system is turned on, the power management module converts the stored energy of the battery (group) into 12V DC required for LED lighting, and the power module detects the voltage of the battery in real time. When the battery voltage is lower than the threshold, the module automatically turns the LED power supply. Enter the mains and complete the conversion from 220V AC to 12V DC. The LED light control module needs to complete the switching, coloring and dimming of the LED light according to the scene setting. LED lamps are currently packaged in 1W or 3W lamp beads, which emit different colors of light through different phosphor LED beads. LED lamp beads are packaged in series, parallel, and hybrid. The LED lamp bead package can be selected according to the color requirements and brightness requirements of landscape lighting. In order to achieve better color reproduction in the landscape lighting system, the system uses red (R), green (G), and blue (B) three-color lamp beads to uniformly package the hybrid mode. The LED light control module controls the brightness of the RGB three color light beads, and forms a plurality of colors through the lens. Controlling the brightness of the LED lamp bead can be realized by changing the LED lamp bead current and adjusting the LED lamp bead lighting time. Relatively changing the current adjustment method, using the LED high-flashing feature to change the LED lighting time is simpler and easier to implement, is currently The main method used to adjust the brightness of the lamp bead. Figure 2 is a schematic diagram of the control principle of a lamp bead (red) in an LED lamp. The integrated circuit U1 is a constant current source chip (XLT604), and supplies power to the red, green and blue lamp beads, and the PWM pin control generates a constant current. Source current size. The P1.5 of the MCU sends out a PWM signal. The duty cycle is different, which causes the red bead to illuminate at different times, so that the red bead emits different brightness. The high and low levels of the MCU P1.2 pin are used to judge whether the red bead is damaged. . Figure 2 LED lamp bead control circuit. The DS2438 chip (internal integrated with temperature sensor, A/D converter, current integrator and other circuits, has many functions such as measuring battery temperature, voltage, current and remaining power). In order to improve the reliability and maintainability of the system, the lighting unit based on the DS2438 designed the overcharge, over discharge, overvoltage, high temperature protection detection circuit for the battery pack and the LED temperature (junction temperature, ring temperature), voltage and current for the important components. Detection circuit. The status detection information is uploaded by the scene controller (sensor gateway) to the monitoring host to provide information for enhancing system management and maintenance, improving battery life, and ensuring reliable system operation. 2.2 Scene Controller The built-in GPRS module of the scene controller communicates with the host computer after accessing the Intenet through the GPRS network. At the same time, in the ZigBee wireless sensor network, its role is the coordinator, responsible for the networking of wireless sensors and management of various sensor devices (lighting units). In the system design, the maximum value of the communication nodes in each sensor network is set to 128, that is, one coordinator and 127 devices. A landscape lighting system may have more than 127 lighting units, that is, there are more than two coordinators and their responsible networks in one system. In the system, a unique 16-bit network PAN ID is set for each coordinator. The ZigBee terminal module embedded in the managed lighting unit needs to set the same PAN ID as the network coordinator, so that the coordinator of the scene controller can be located. A request to join the network for the same PAN ID terminal within its network coverage is accepted, and then information for the new lighting unit node is added. During system operation, the scene controller does not process and save the information sent by the monitoring host and the lighting unit. It directly sends the status detection information sent by the lighting unit to the monitoring host through the local area network, and sends the instructions issued by the monitoring host to each. Lighting unit. The monitoring host is responsible for the information processing judgment of multiple scenes and lighting units of the entire system. The scene control in the system acts as a sensor gateway, responsible for communication with various devices and communication with the Intenet network. The sensor gateway hardware consists of an MCU unit, a GPRS module unit, a ZigBee module unit, a power management unit, and a clock unit. The power management unit input voltage converts the battery pack voltage to 4.1V required by the GPRS module, the 5V required by the MCU, and the 3.3V required by the MCU module. The UART0 and UART1 of the MCU module are respectively connected to the GPRS and ZigBee modules for Implement network control and communication. In the circuit design, it should be noted that the large current when the GPRS module is started will cause the voltage to drop by 0.6~0.7V. It is necessary to design 1~2 100μF tantalum capacitors between the 4.1V output terminal and the ground to avoid the voltage drop to 3.0V. Restart caused by GPRS module protection. The scene controller uses the NXPLPC1766 microcontroller (containing 256 KBFLASH, 64 KB RAM), and its two UART ports are connected to the GPRS module and the ZigBee transceiver module respectively. The software implements UDP and IP protocol stack based on embedded operating system μC/OSII. The monitoring host in the system can realize information interaction with the gateway through UDP protocol. 2.3 Monitoring host The monitoring host in the system is the information center of the whole landscape lighting system. When the system is running, the host computer software receives the status information of the lighting unit forwarded from the scene controller via the Intenet, and sends a query and setting instructions to the scene controller according to the scene setting requirements, and then Forwarded by the scene control to the corresponding lighting unit. The monitoring host is also the control center of the system, and the configuration controls the startup time of the entire system lighting unit, the color of the light source and the light intensity. The system is set in units of scene controllers. Each lighting unit controlled by the scene controller can be configured with parameters such as red, green, and blue light bulb flashing parameters of 1 byte each (value 0~255), each The scene contains a 16-bit scene controller number, scene code (8 bits), and a 127 x 32-bit lighting unit. The software provides an editing function that encodes the edited results and stores them in a local hard disk file. The start time is added to the specified scene controller. The monitoring PC software provides functions such as dynamic analysis, alarm and maintenance prompts of the system running status. 3 Network communication protocol description Landscape lighting control system local communication uses ZigBee wireless sensor network, which is widely used at present, is a low-rate, low-power, short-distance wireless communication technology. ZigBee supports multiple networking modes. The system uses star topology networking based on efficiency and reliability considerations. That is, each landscape lighting system deploys one to multiple Co-ordinators (scene controllers) as needed. Communicate directly with the Sensor device. Since each sensor network can only have one PAN Co-ordinator, the monitoring host in the system manages multiple scene controllers through the Intenet, and each scene control is responsible for the network of one sensor network. (1) Sensor network networking process The system pre-defines a PAN ID as the identifier of the network for each Co-ordinator. The scene controller broadcasts the broadcast frame 60s after the scene controller is started (reset), and opens the request response of the Sensor device (lighting unit) to join the network. Once the unit is started or reset, the channel is scanned periodically. Once the scene controller that is available in the network is found, a request is made. After the scene controller detects the request, it determines that the lighting unit information is determined, and accepts or rejects the device. Network, update your own network table at the same time. (2) Sensor network information communication In the system, the data transmission between the sensor network scene controller and the lighting unit adopts the direct transmission mode (no intermediate device forwarding), that is, the scene control directly sends the data to the lighting unit, and when the lighting unit receives the data, sends the confirmation information to the scene controller. . The data transmission method requires the end node device to be in the data receiving state at any time, that is, it is required to be in a state of waking up at any time. The scene controller sends information by using the unicast mode to poll each sensor node. After the scene controller is started, the time slice wheel is started. According to the order of each lighting unit in the network table, the data transmission request frame is periodically sent to the lighting unit for polling, and the lighting unit After receiving the transmission request frame, the response frame is returned, and the response frame includes its status information (such as battery voltage, power supply, current setting, lamp color brightness, etc.). (3) Communication between sensor network and host computer The scene controller starts to obtain the IP address and establishes a network table. It periodically (default 5 min, configurable) reports the status information of the lighting unit in the sensor network to the upper computer. The host computer sets the polling interval of the scene controller through the network, and verifies the local clock of the scene controller and the network scene (lighting unit parameter set). (4) System synchronization The realization of the scene effect in the landscape control needs to be coordinated between the lighting units, which requires solving the synchronization problem of each lighting unit. The system adopts a two-level synchronization mechanism to solve the synchronization problem. The verification time frame is used between the host computer software and the scene controller communication protocol, and the upper computer periodically sends the time check frame. The scene controller obtains the host computer time through the frame, and checks the correction. local time. In the sensor network, the scene controller is used to transmit a broadcast pulse frame every 60s to realize synchronization between nodes of the managed network. The pulse frame includes counter update data in seconds, and the lighting unit updates the timing local timer after receiving the broadcast pulse frame. The value of the count, the internal timer of the lighting unit counts the value of this timer every 1 s. 1. The sensor gateway broadcasts the current time information every 10s. The sensor gateway has a clock chip. The internal time counting unit of the sensor network is seconds, and the sensor gateway will clock. The chip's HH:MM:SS is converted into one-second count. Each sensor device receives this time data, updates the internal time counter, and each sensor device timer 1s is interrupted once. The time counter in the interrupt service is incremented by 1. (5) Main transmission data The communication data frame between the monitoring host and the scene controller and the scene controller and each lighting unit in the system mainly includes: Among them: the scene setting instruction frame is sent by the monitoring host when changing the landscape lighting or timing to start different scenes according to the operation requirements of the upper computer. The scene control receives the instruction frame and responds to the response frame (including the status information of the lighting unit of the network). The status request frame is sent by the operator at any time through the host computer software, and the scene controller receives the request frame and replies to the response frame. The systolic frame reports the network status information periodically by the scene controller. The pulsation frame has the same format as the response frame, the frame number of the pulsation frame is 0, and the acknowledgment frame number is the same as the received instruction or query sequence number. The pulsation (response frame) format is shown in Figure 3. Figure 3 response frame format The lighting unit timing measurement status information (1s detection once), the illumination unit response frame is in accordance with its pulsation frame format, and the information includes temperature (1B), humidity (1B), battery voltage (1B), power supply status (battery, mains, battery) + Mains) with lamp bead condition (1B). 4 Conclusion This paper introduces a design of landscape lighting system based on ZigBee sensor network. The system uses sensor network to realize real-time detection and centralized control of the status of many lighting units in the system. The system's proposed detection and control communication mode ensures multi-scene space. The coordination of the switching is synchronized and the real-time performance is strong. It runs reliably in urban main park applications, and the setting of multiple scenes is convenient and automatic switching is accurate. At the same time, the system can also be applied to places with many lighting units such as parks and stadium lighting. references:

Researchers Hu Shuju, Meng Yanfeng, Li Fenglin, Song Bin, and Deng Ya from the Institute of Electrical Engineering, Chinese Academy of Sciences, in the 24th issue of Journal of Electrical Engineering, in the study of a non-ideal grid voltage condition, to study a voltage imbalance in the grid. The grid-connected inverter has no AC voltage sensor control strategy. Firstly, based on the second-order generalized integrator, the orthogonal filter and the three-phase grid-connected inverter voltage observer suitable for the grid voltage unbalance condition are constructed, and the grid voltage is observed in the two-phase stationary coordinate system; then based on the orthogonal filter The output is positively and negatively sequenced, so that the positive and negative sequence separations are synchronized with the grid voltage observation. Finally, the inverter is combined with the PR control in the two-phase stationary coordinate system, and the negative sequence compensation algorithm is used to realize the inverter. No AC voltage sensor control under grid voltage imbalance conditions. This strategy can avoid the problems of integral saturation, initial value sensitivity and static error in traditional virtual flux linkage observation, and overcome the problem that the existing orthogonal filter-based inverter without AC voltage sensor can not adapt to the grid voltage imbalance. . The effectiveness of the proposed strategy is verified by simulation and experiment. When a renewable energy power generation system is connected to a power distribution network such as an inverter or a distribution network with a weak grid structure, some non-ideal conditions that may exist in the grid voltage may adversely affect the stable operation of the grid-connected system. [1]. In view of the grid-connected inverters, in recent years, some researchers at home and abroad have begun to study the AC-free voltage sensor control that does not rely on the grid voltage signal to improve the adaptability of the inverter under non-ideal grid conditions [2, 3]. Similar to voltage sensor control, in a voltage-free sensor control algorithm, the reconstructed voltage/virtual flux linkage signal can be explicit and vector controlled; it can also be implicit and direct power control. The existing grid voltage/virtual flux linkage reconstruction methods can be roughly divided into two categories: one is the grid voltage/virtual flux reconstruction method based on complex power estimation, which belongs to the open loop estimation method, and the accuracy is not high, and The current differential term is easy to cause interference; the second is the grid voltage/virtual flux reconstruction method based on the grid side current deviation adjustment, which belongs to the closed loop estimation method and has high accuracy. In order to reduce interference and improve the accuracy of observation, it is generally necessary to use a low-pass filter, but the low-pass filter itself has problems such as zero drift, integral saturation, steady-state error, and initial value sensitivity [4, 5]; When the voltage is unbalanced, the cascade algorithm of flux linkage observation and positive and negative sequence separation makes the control structure more complicated, increases the delay time and reduces the dynamic response speed of the system [6]. In [7], an inverter-free AC voltage sensor control method based on quadrature filter is proposed, which can realize the AC-free voltage sensor control of the inverter under the condition of grid voltage balance. Based on the virtual synchronous machine technology, the literature [8,9] introduces a virtual current to synchronize the voltage control signal with the grid voltage, which can well track the amplitude, frequency and phase of the fundamental component, but not for the non-ideal grid voltage. Conditions are specifically studied. In [10], based on the instantaneous power theory and virtual flux linkage technology, the literature [10] proposes two improved AC voltage-free sensors that adapt traditional direct power control to grid disturbances and operate well. The situation requires further experimental verification. Therefore, for the inverter-free voltage sensor control of grid voltage imbalance conditions, both the construction of the filter and the control strategy of the inverter need further research, verification and improvement. Aiming at the above problems, this paper studies the inverter-free AC voltage sensor control strategy under the condition of grid voltage imbalance. Based on the second-order generalized integrator, a variable frequency orthogonal filter is constructed to further establish a voltage observer. The method of separating the positive and negative sequence components based on the orthogonal filter makes the voltage observation and voltage and current positive and negative sequence separation can be completed simultaneously, and the negative sequence compensation current control realizes the inverter without AC voltage sensor control, thereby simplifying The control structure of the system and get better dynamic performance. Finally, the simulation and experimental verification results and conclusions are given. Figure 1 Structure diagram of variable frequency orthogonal filter Figure 2 Experimental system structure Figure 3 experimental system device physical map in conclusion In this paper, we propose to establish a variable frequency orthogonal filter based on the second-order generalized integrator, and further construct a voltage observer that adapts to the grid voltage imbalance condition, and perform positive and negative sequence separation based on the output of the orthogonal filter to make positive and negative The sequence separation is synchronized with the grid voltage observation, combined with the negative sequence current compensation control, to achieve the inverter-free AC voltage sensor control under the grid voltage imbalance condition. The effectiveness of the proposed control strategy is verified by simulation and experiment. The proposed AC-free voltage sensor control strategy can adapt to the grid voltage imbalance condition and reduce the inverter hardware cost, which can effectively improve the grid adaptability of the grid-connected inverter. The next step will be to further improve the method proposed in the current inverter without voltage sensor control, and compare it with other methods.

Introduction Servo technology is a tracking and positioning control technology and an important part of electromechanical integration technology. It is widely used in automation equipment such as CNC machine tools and industrial robots. With the continuous expansion of modern industrial production, the demand for electric servo systems in various industries is increasing day by day, and higher demands are placed on their performance. Therefore, researching and manufacturing high-performance, high-reliability servo drive systems is a goal that industrial advanced countries are striving to achieve. It has very important practical significance. At present, digital servo drives are basically monopolized by Japan, Europe and the United States. Every year, China needs to import a large amount of such equipment from abroad for CNC machine tools and other industries. The price of imported drives is high and maintenance services are inconvenient. The all-digital servo driver with independent intellectual property rights in China began to be manufactured in large scale in the 1990s. Huazhong CNC hsv series digital AC servo motor drive unit has good performance. The speed ratio of all-digital AC servo system independently developed by our company is 1:5000. High-end products often use foreign AC servo systems, mainly domestic servo drive controllers in high-speed and high-precision control characteristics, compared with Japan's fanuc, Mitsubishi, Panasonic, Fujitsu and Germany's Siemens and other foreign advanced products, There is a significant gap. Servo Control System Hardware Design The digital servo system is mainly composed of five parts: a permanent magnet synchronous motor, a power supply module, a drive and inverter circuit module, a speed and position detection circuit module, and a control circuit module. The control circuit module includes the core control chip, human-machine interface and communication module; the drive and inverter circuit module includes the inverter main circuit, voltage/current sampling circuit, overvoltage/undervoltage protection, and current limit protection. Brake circuit, digital servo control system hardware block diagram shown in Figure 1. The tms320f2812dsp is the control core and receives information from the CNC, the encoder interface, the current detection module, and the fault signal processing module to complete the control and troubleshooting of the permanent magnet synchronous motor. Optical isolation module as the interface between the electronic circuit and the power main circuit, the svpwm signal sent by the dsp is sent to the ipm module to complete the dc/ac inversion and drive the motor to rotate. The encoder interface sends the magnetic pole position, motor steering and encoder alarm information of the permanent magnet synchronous motor recorded by the absolute encoder to the dsp, and sends the position information of the permanent magnet synchronous motor to the cnc. The motor phase current is measured, filtered, amplitude-converted, zero-shifted, and limited by the current detection module, and converted into 0~3v voltage signal and sent to the dsp a/d pin. Power over-voltage, under-voltage, short-circuit, power-failure, and IPM faults of the power main circuit are detected and processed by the fault detection module and sent to the i/o port of the dsp. The keyboard and display module are the man-machine interface of the controller, used to complete the input of control parameters, and display the operating status and operating parameters. The memory module is used to store control parameters and system fault information. The servo's core control chip adopts tm320f2812, the latest motor-specific control chip from Ti. It has the following outstanding performance compared to other similar dsps: Using high-performance static CMOS technology, the main frequency can reach 150mips, shorten the instruction cycle to 6.67ns (150mhz), and use 32-bit operation, thereby greatly improving the processing capability; Low power consumption, supply voltage drop 1.8v (core) and 3.3v (i/o); On-chip up to 128k words flash program memory, 18k saram and 4k rom; With 12-bit a / d converter, the minimum conversion time is 80ns. The inverter circuit uses Mitsubishi's ipm module. The smart power module uses a 5th generation igbt process, with an optimized gate drive and protection circuit, and an incredibly ultra-compact volume with three-phase waveforms with powerful output power. It has the following outstanding performance: Complete power output circuit, directly connected to the load; Built-in gate drive circuit; Short circuit protection; Drive voltage undervoltage protection; Adopt fifth-generation low-power igbt die; Ultra-small size, weighing only 65g. Digital servo system control strategy Digital servo system is generally completed by three closed loops. The principle is shown in Figure 2. The first layer is the position loop, the second layer is the speed loop, and the third layer is the current loop; where the position and speed are all outer loops, and the current loop is the inner loop within the system. The composition is composed of core hardware and key solution software. The all-digital servo system is the core transmission part of the CNC machine tool, and it is also the most technically difficult part. Its main features are high speed, high precision, and rich and varied functions. The current loop is the core control loop of the servo system, and the key to ensure the speed accuracy and the torque stability is the design of the current loop in the digital servo. Therefore, whether a system performance is excellent is closely related to the design of the current loop. The design of the lem sensor and current sampling circuit scheme directly results in the accuracy of the entire current loop because of the accuracy and speed of sampling, and thus has a very significant impact on the performance of the system. In the field of power parameter measurement, the Hall current sensor, which is the leading manufacturer of Lem, has become the first choice for this system design due to its stable and reliable product performance. The model number is lts25-np. This sensor uses a single-supply power supply. Compared to a dual-supply power sensor (see Figure 3), the Lamb sensor has a simpler peripheral hardware design and does not require an additional voltage boost circuit (a dual-supply sensor must Increase the voltage raising circuit to convert the negative voltage into a positive voltage before entering the dsp) to reduce the interference of the power supply to the system. Another advantage of this sensor is the small temperature drift, high precision; and built-in sampling resistor, the output is a voltage-type output, to avoid the increase in the external sampling resistor and ops to enter the dsp to reduce the accuracy. The specific characteristics and performance parameters of the lts25-np sensor are as follows: The original side rated current effective value ipn: 25a; The primary current measurement range ip: 0 ~ ± 80a; Supply voltage: +5v; Output voltage vout: 2.5 ± 0.625v; The conversion rate kn=np:ns is: 1:2000; Total accuracy: ±0.2%; Linearity: less than 0.1%; Reaction time: less than 500ns. The sensor has three pins: positive (+5), measuring (out), and ground (0), as shown in Figure 3. Its working principle is as follows: This sensor is a closed loop Hall current sensor, uses the Hall device as the core sensitive element, the modular product for isolating and detecting the electric current, its working principle is the magnetic balance type of Hall (or call Hall magnetic Compensation type, Hall zero flux type). When a current flows through a long straight wire, a magnetic field is generated around the wire. The size of the magnetic field is proportional to the size of the current flowing through the wire. This magnetic field can be collected by a soft magnetic material and then detected by a Hall device. Since the change of the magnetic field has a good linear relationship with the output voltage signal of the Hall device, the measured output signal can directly reflect the current in the wire. In order to prevent interference, a 1μf decoupling filter capacitor is separately connected to the power supply terminal and the ground terminal of the Hall sensor. The current detection circuit converts the three-phase stator current of the permanent magnet synchronous motor into the dsp through the sensor and converts it into a digital form and performs a series of transformations. Since this system is a three-phase balanced system: ia+ib+ic=0; therefore only Need to detect the two-phase current, you can get three-phase current. From the mathematical model of the permanent magnet synchronous motor, we can see that the stator current detection accuracy and real-time is the key to the accuracy of the entire vector control system, so the system uses lts25-np sensor to detect the current. In this system, the current of phase a and phase b is detected by two lem modules. In actual debugging, since the current signal passing through the sensor has high-order ripple and other interference signals, a filter must be designed to suppress high-order chopping waves and other interference signals. Considering the actual situation, this paper designs a current detection circuit with a second order low-pass filter with voltage follow-up. The specific schematic is shown in Figure 4. Under the switch mode control, the phase current signal contains higher harmonics that need to be filtered out. In the design, first use the pspice software to carry on the fictitious design to the filter [2 ], after confirming and verifying through the simulation, confirm and adopt the Butterworth filter structure of the second order, the system uses the electric current sensor to measure the electric current, have filtered, amplitude transform, zero deviation Move and clip, convert the voltage signal of 0~3v into the a/d pin of dsp. The amplitude-frequency characteristics of the second-order Butterworth filter (shown in dashed box) in Figure 4 are shown in Figure 5. The frequency response curve in the passband is as flat as possible. The cut-off frequency is 300hz and the attenuation slope is -40db. /dec. Experimental Results In the experimental system, the pwm frequency is 15khz, the dead time is 3μs, the current loop sampling period is 67μs, the speed loop sampling period is 0.67ms, the output loop of the speed loop is 1.5 times the rated current, and the current loop output Limiting is 1.2 times the rated voltage. Experimental control of an 8-pole permanent magnet synchronous motor motor, the parameters are: rated power: 1.88kw, rated speed: 2500r/min, rated current: 7.5a, rated torque: 7.5nm, rated voltage: 220v. The motor is at 10r/min, 200r/min, 1000r/min, 2000r/min and the speed regulator parameter is set to: kpv=0.5, kiv=0.02; the current regulator parameter is set to: kpi=0.2, kii=0.02 The start-stop speed curves are shown in Figures 6-9, respectively. From the experimental waveforms shown in Figs. 6-9, it can be seen that when the motor is running at no-load, the system operates in the closed state of the speed current, and the steady state can be reached quickly. The overshoot and steady state errors are small. The experimental results show that the system Reasonable design, with good dynamic and static properties. Conclusion In this system application, lem sensor can measure the motor current correctly and convert it into the corresponding output. All the performance indicators can meet the requirements of this system. It is a very good product. In summary, using the Hall current sensor (lem module) to sample the current, the linearity is good, the power consumption is small, the temperature stability is good, and the accuracy is generally higher, so it is an ideal current sensor. During the development of this system, we greatly thanked the engineers of the company for their thoughtful service and technical support. Hope that after the lem electronics company can provide more products and better technical support, together with China's high-end servo control industry to achieve greater development efforts.

Recently, Turck introduced linear displacement sensors for hydraulic cylinders - the new magnetostrictive LTX series linear displacement sensors. The sensor can achieve liquid level detection through the use of float-type positioning magnetic blocks. Depending on the high seismic resistance and impact resistance of the sensor, this series of sensors can also be applied to construction machinery and other harsh working environments. This series of products completes the family of inductive linear displacement sensors, especially where magnetic positioning blocks must be used. The LTX-Series products meet the IP68 protection rating while it has anti-corrosive properties for many chemicals and oils. The high quality stainless steel housing protects the product from working in many corrosive environments. The LTX series linear displacement sensor uses a wear-free detection method, which ensures that it can provide a precise signal output with high linearity and repeatability. It can provide analog signal output (4-20 mA or 0-10 VDC signal) or SSI digital signal output with high precision. A three-color LED indicator can show the working status of the sensor. The low input power (1 watt) version can be connected directly to the display module, control module or interface module. The easy programming of LTX series sensors makes it easy to adjust the detection range. For setting a smaller measurement range, the product can be set up again in a matter of seconds. Therefore, the series of sensors with good versatility can effectively reduce the inventory pressure of different sensor products during use.

There is no limit to creativity, and the instrument is invented. Today we introduce a patent for national inventions - sensor control devices and sensor control systems. The patent was filed by Japan Special Ceramics Co., Ltd. and was authorized to be announced on April 12, 2017. Description The present invention relates to a sensor control device and a sensor control system, wherein the sensor control device and the sensor control system measure, for example, a concentration of a specific component in an object measurement gas such as an aerated mixture of an internal combustion engine, and are suitable for use in an oxygen sensor The output signal is compensated. Background of the invention In recent internal combustion engines, in order to improve fuel economy and reduce harmful substances contained in exhaust gas, control of an air-fuel ratio as a ratio of fuel to intake air is generally performed, particularly for fuel versus intake air. Control of the ratio of oxygen contained in the medium. When this control is performed, it is necessary to measure the volume of the intake air. For example, a method of using an air mass flow sensor for measuring the volume of intake air is known. The air mass flow sensor is used in an internal combustion engine equipped with an intake throttle valve and can be used to measure an in-cylinder intake air volume that changes according to an operating state. On the other hand, an intake throttle valve is not provided in a diesel engine, a direct injection gasoline engine, or the like, and the intake air volume in the cylinder is substantially constant. Further, in a diesel engine having an exhaust gas recirculation device (hereinafter referred to as "EGR device") for recirculating a part of the burned exhaust gas into the intake air, the ratio of oxygen contained in the intake air It is changed by the amount of exhaust gas for recirculation (hereinafter referred to as "EGR amount"). In other words, the amount of oxygen in the cylinder changes. In this case, it is difficult to precisely control the air-fuel ratio using only the above-described air mass flow sensor. That is, in the control of the air-fuel ratio using only the air mass flow sensor, the in-cylinder oxygen ingress is calculated on the assumption that the ratio of oxygen contained in the intake air is the same as the ratio of oxygen contained in the air, for example. the amount. Since the ratio of oxygen contained in the intake air is changed in the internal combustion engine equipped with the EGR device, it is impossible to accurately calculate the in-cylinder oxygen intake amount. Summary of the invention It is known that in the case of using an oxygen sensor as described above, it is necessary to compensate for variations in output values due to, for example, deterioration of the oxygen sensor. In particular, in the case where the oxygen sensor is disposed only in the intake system, high oxygen sensor accuracy is required. Further, the necessity of compensation is improved as compared with the case where the oxygen sensor is disposed in the intake system and the non-intake system. For this reason, the technique disclosed in JP-A-H02-221647 also compensates for the output value of the oxygen sensor after the internal combustion engine is stopped. However, power is always consumed in the case of compensating for the output value of the oxygen sensor, and in the case of the vehicle, the power is supplied from the installed battery. When the power of the battery is insufficient in the case where the compensation is performed after the internal combustion engine is stopped as disclosed in JP-A-H02-221647, there is a fear that the compensation cannot be performed in an accurate state. More specifically, there may occur a case where the heater of the oxygen sensor cannot be sufficiently driven, or a case where the temperature of the sensing element cannot be accurately controlled. Further, even in the case of performing compensation, there is a fear that the battery is easily exhausted due to the consumption of power of the battery. The drawing shows a schematic diagram of the overall structure of a sensor control system according to a first embodiment of the present invention. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a sensor control apparatus and a sensor control system capable of suppressing a heater equipped with a heater while suppressing power consumption of a battery installed together with an internal combustion engine The measurement accuracy of the oxygen sensor is deteriorated. In the first aspect (1), the above object of the present invention has been achieved by providing the following: a sensor control device for connecting to an oxygen sensor, the oxygen sensor comprising: a sensing element for measuring the progress of the internal combustion engine An oxygen concentration in the gas; and a heater for heating the sensing element, the sensor control device comprising: a detecting unit configured to detect a output corresponding to the oxygen concentration output from the sensing element An output signal; and a calculation unit for calculating a compensation coefficient of an output signal used for calculating the oxygen concentration, wherein the internal combustion engine is in operation and is capable of estimating an oxygen concentration in the intake air In the case of a specific operational state, the calculation unit collects compensation information used in calculating the compensation coefficient. According to the sensor control device of the present invention, in the case where the internal combustion engine is in operation and in a specific operational state capable of estimating the oxygen concentration in the intake air, collection of compensation information for calculating the compensation coefficient is performed. Therefore, the compensation coefficient for compensating the output signal of the sensing element based on the compensation information can be calculated and updated. Thus, even in the correspondence relationship between the value of the output signal of the sensing element and the oxygen concentration in the intake air, due to, for example, deterioration of the sensing element, the compensation coefficient calculated in the calculation unit can be used. The output signal is compensated to eliminate the deviation of the corresponding correspondence. Further, in the present invention, as described above, in the case where the internal combustion engine is in operation, the calculation unit collects compensation information used to calculate the compensation coefficient. The timing at which the calculation unit calculates and updates the compensation coefficient of the output signal may be the time when the internal combustion engine is in operation and may be the time when the internal combustion engine is in the non-operating state. There is no specific limit to this moment. Further, in the sensor control device of the present invention, since the calculation unit collects the above-described compensation information in the case where the internal combustion engine is used to drive the generator and the battery mounted together with the internal combustion engine is charged, the compensation information is collected in the case where the internal combustion engine is stopped. In comparison with the case, the power consumption of the battery can be suppressed. In other words, the specific operational state capable of estimating the oxygen concentration in the intake air is a state in which the oxygen concentration previously stored in the calculation unit and the oxygen concentration in the intake air are the same. Further, the state in which the internal combustion engine is in operation refers to, for example, a state in which the internal combustion engine is driven (including an idling operation state) in a case where the key is not in an OFF (OFF) state. Further, the state in the case where the internal combustion engine is driven for a certain period of time is included in a state in which the internal combustion engine is in operation, regardless of whether or not the vehicle is traveling in the case where the internal combustion engine is installed in the vehicle. In a preferred embodiment (2) of the sensor control device (1) of the present invention, the specific operational state is an opening degree of a control valve provided in the exhaust gas recirculation device for controlling the amount of exhaust gas for recirculation. a state less than a predetermined opening degree, wherein the exhaust gas recirculation device is configured to recirculate a portion of an exhaust gas of the internal combustion engine into the intake air, and an opening degree of the control valve is smaller than the predetermined opening degree The oxygen concentration in the intake air is previously stored in the calculation unit, and in a case where the opening degree of the control valve is smaller than the predetermined opening degree, the calculation unit collects the compensation information. In a second aspect, the above object of the present invention is also achieved by providing an oxygen sensor comprising: a sensing element for measuring an oxygen concentration in an intake of an internal combustion engine, and a heater for sensing the feeling The measuring component performs heating; a state measuring unit for outputting a state signal corresponding to an operating state of the internal combustion engine; and a determining unit configured to determine whether the internal combustion engine is in a specific operating state based on the state signal; The sensor control device according to (1), wherein the calculation unit of the sensor control device collects the compensation information based on a determination result of the determination unit. According to the invention, the sensor control device and the sensor control system can suppress the deterioration of the measurement accuracy of the oxygen sensor equipped with the heater while suppressing the power consumption of the battery mounted together with the internal combustion engine. This is because the compensation coefficient is calculated based on the compensation information collected in the case where the internal combustion engine is in operation and is in an operating state capable of estimating the oxygen concentration in the intake air.

According to the James Consulting, researchers from the Belgian Microelectronics Research Center (IMEC) and the Dutch Applied Science Organization (TNO), the Holst Center researchers showed a test for detecting fingers. New flexible, large area sensor technology for palm prints. With a thickness of less than 0.2 mm and no large prisms or moving parts, the new sensor can be embedded in objects such as mobile phones and door handles to create an "invisible" but secure access control system that recognizes that the scanned object is alive rather than a phantom. Or a fake person. The technology paves the way for low-cost sensors for large-area finger and palmprint scanners, which will be on display at the Information Display Association (SID) 2018 Display Week Innovation Zone in Los Angeles, USA, and will be in Belgium. The IMEC Technology Forum (ITF) in Antwerp is on display. The two demonstration machines will demonstrate the technological potential for high resolution and large area effective detection areas. Among them, the 6 x 8 cm, 200-ppi demonstration machine is large enough for the 4-finger scanners currently used by border management and provides adequate image quality for basic identification applications. At the same time, the slightly smaller 500 ppi demonstration machine provides higher image quality, meets FBI standards, and is sufficient for law enforcement agencies to visualize details and pores for more powerful identification. Like the Holst Center's early flexible X-ray detectors, this fingerprint sensor combines an organic photodiode front panel, an oxide thin film transistor (TFT) backplane (originally developed for flexible displays) and a thin film barrier for protection. Together. All three technical elements have been or are being transferred to industrial production to expand and commercialize. The sensor reads hand fingerprints or palm prints by detecting visible light (400 to 700 nanometers) reflected from the skin surface. Moreover, they can also detect part of the light that penetrates the skin before reflection. This allows them to perceive the heartbeat from changes in the capillaries of the hand, thereby verifying that the scan mark is from a living person. In addition, by using different photodiode materials, the sensor's functionality can be extended to other wavelengths, such as near-infrared (NIR). This technology will enable new authentication modes, such as identification by hand vein pattern, which is even more specific to individuals than fingerprints. Near-infrared sensors can also be used for other purposes such as blood oxygen monitoring, night vision and 3D facial recognition. Holz Center project manager Hylke Akkerman said: "The flexible fingerprint sensor demonstration machine demonstrates the versatility and maturity of the flexible electronics technology being developed by Holst Center. Since the underlying technology has been applied to the flat panel industry, it is the new flexibility. The manufacture of fingerprint sensors has established a fast track, and we are looking for industry partners to take this step."

The linear displacement sensor works on the same principle as a sliding rheostat. It is used as a voltage divider to present the actual position of the measured position with a relative output voltage. There are several requirements for the operation of this device: First, if the electronic ruler has been used for a long time, and the seal has been aging, and there are many impurities, and the water mixture and oil will seriously affect the contact resistance of the brush, so that the displayed number will continue to jump. At this time, it can be said that the electronic scale of the linear displacement sensor has been damaged and needs to be replaced. Second, if the capacity of the power supply is small, there will be many situations, so the power supply needs to have sufficient capacity. Then, if the capacity is insufficient, it will cause the following situation: the movement of the glue will change the display of the clamped electronic ruler, and there will be fluctuations, or the movement of the mold will cause the display of the electronic ruler to fluctuate, resulting in a large error in the measurement result. If the driving power of the solenoid valve is at the same time when the power supply of the electronic scale is together, the above situation is more likely to occur. When the situation is serious, the voltage fluctuation of the multimeter can even measure the fluctuation of the voltage. If the situation is not caused by high frequency interference, static interference or neutral neutrality, then it may be caused by the power of the power supply being too small. Third, FM interference and static interference are all possible to make the digital display of the linear displacement sensor jump. The signal line of the electronic ruler and the strong electric line of the device are separated from the wire slot. The electronic ruler must use the grounding bracket forcibly, and at the same time let the outer casing of the electronic ruler be in good contact with the ground. A shielded wire is required for the signal line, and a section of the electrical box should be grounded to the shielded wire. If there is high frequency interference, the voltage measurement using the multimeter will usually display normal, but the display number will be non-stop; when static interference occurs, the situation will be the same as high frequency interference. To prove whether it is static interference, you can use a power cord to short the cover screw of the electronic ruler with some metal on the machine. As soon as it is shorted, the static interference will be eliminated immediately. of. However, if it is necessary to eliminate high-frequency interference, it is difficult to use the above method. Frequency conversion power savers and robots often have high-frequency interference, so you can try to verify whether it is high by stopping the high-frequency power saver or robot. Frequency interference. 4. If the electronic scale of the linear displacement sensor is in the process of working, the display data at a certain point is beating regularly, or when the data is not displayed, it is necessary to check whether the insulation of the connecting wire is damaged or not. And short circuit to ground caused by regular contact with the outer casing of the machine. 5. The voltage of the power supply must be stable. The voltage of the industry needs to meet the stability of ±0.1 [%]. For example, if the reference voltage is 10V, the fluctuation of ±0.01V can be allowed. If not, it will cause display. The traps fluctuate like this. However, if the amplitude of the display fluctuation at this time does not exceed the fluctuation of the fluctuating voltage, then the electronic ruler is normal. Sixth, the alignment of the linear displacement sensor needs to be very good, but the parallelism can allow an error of ±0.5mm, and the angle can allow an error of ±12°. However, if the parallelism error and the angle error are both too large, there will be a case where the digital jitter is displayed. Then, when such a situation occurs, the parallelism and angle must be adjusted. Seventh, in the process of connection, we must pay more attention, the three lines of the electronic ruler can not be connected wrong, the power line and output line can not be exchanged. If the above line is wrong, there will be a large linearity error. It is difficult to control, the accuracy of the control will be poor, and the display will be prone to jitter.

1 Introduction to TSL256x TSL2560 and TSL2561 are a high-speed, low-power, wide-range, programmable and flexible configuration of light intensity digital conversion chips introduced by TAOS. The chip can be widely used in the monitoring of various display screens, the purpose is to make the display screen provide the best display brightness and reduce the power consumption as much as possible under changing lighting conditions; it can also be used for street lighting control and safety lighting And many other occasions. The main features of this chip are as follows: Programmable upper and lower thresholds for permitted light intensity, and an interrupt signal is given when the actual light intensity exceeds this threshold; Digital output conforms to standard SMBus (TSL2560) and I2C (TSL2561) bus protocols; Programmable control of analog gain and digital output time; 1.25 mm & TImes; 1.75 mm ultra-small package, in low power mode, power consumption is only 0.75 mW; Automatically suppress 50 Hz / 60 Hz light fluctuations. 2 TSL256x pin function TSL256x has 2 kinds of packaging forms: 6LEAD CHIPSCALE and 6LEAD TMB. Different packaging forms have different formulas for calculating the corresponding illuminance. The functions of each pin are as follows: Pin 1 and pin 3: Power pin and signal ground respectively. Its operating voltage range is 2.7 ~ 3.5V. Pin 2: Device access address selection pin. Due to the different levels of this pin, the device has 3 different access addresses. The corresponding relationship between the access address and the level is listed in Table 1. Pin 4 and pin 6: I2C or SMBus bus clock signal line and data line. Pin 5: Interrupt signal output pin. When the light intensity exceeds the upper or lower threshold set by the user, the device will output an interrupt signal. 3 TSL256x internal structure and working principle TSL256x is the second-generation ambient light intensity sensor, and its internal structure is shown in Figure 2. Channel 0 and channel 1 are two photodiodes, where channel 0 is sensitive to both visible light and infrared light, while channel 1 is only sensitive to infrared light. The integral A / D converter integrates the current flowing through the photodiode and converts it into a digital quantity. After the conversion is completed, the conversion result is stored in the registers of channel 0 and channel 1 inside the chip. When one integration cycle is completed, the integral A / D converter will automatically start the next integral conversion process. Microcontroller and TSL2560 can be realized through standard SMBus (System Management Bus) V1.1 or V2.0, TSL2561 can be accessed through I2C bus protocol. The control of TSL256x is realized by reading and writing 16 internal registers. 4 TSL256x application design The access of TSL256x follows standard SMBus and I2C protocols, which makes the hardware and software design of the chip very simple. Although the read and write timings of these two protocols are very similar, there are still differences. The following uses only the TSL2561 chip as an example to illustrate the practical application of the TSL256x light intensity sensor. 4.1 Hardware design TSL2561 can be accessed through the I2C bus, so the hardware interface circuit is very simple. If the selected microcontroller has an I2C bus controller, the clock line and data line of the bus are directly connected to the SCL and SDA of the I2C bus of the TSL2561; if there is no pull-up resistor inside the microcontroller, you need to Then use 2 pull-up resistors to connect to the bus. If the microcontroller does not have an I2C bus controller, connect the SCL and SDA of the TSL2561's I2C bus to the ordinary I / O port; but when programming, you need to simulate the timing of the I2C bus to access the TSL2561, and the INT pin is connected to the micro control The external interruption of the device. 4.2 Software design The microcontroller can read and write the TSL2561 through the I2C bus protocol. When writing data, send the device address first, then send the data to be written. The write operation of TSL2561 is as follows: First send a group of device addresses; then write the command code, the command code is to specify the address 00h ~ 0fh of the next write register and the way to write the register, which is a byte, word or block ) The unit performs write operations; finally send the data to be written, according to the previous command code to specify the way to write the register, you can continuously send the data to be written, the internal write register will automatically increase by 1. For the specific reading and writing timing of the I2C protocol, you can refer to the relevant information, and I will not repeat them here. Due to space limitations, here are some programs to read and write TSL2561: unsigned char TSL2561_write_byte (unsigned char addr, unsigned char c) { unsigned char status = 0; status = twi_start (); // Start status = twi_writebyte (TSL2561_ADDR | TSL2561_WR); // Write TSL2561 address status = twi_writebyte (0x80 | addr); // Write command status = twi_writebyte (c); // write data twi_stop (); // stop delay_ms (10); // delay 10 ms return 0; } unsigned char TSL2561_read_byte (unsigned char addr, unsigned char * c) { unsigned char status = 0; status = twi_start (); // Start status = twi_writebyte (TSL2561_ADDR | TSL2561_WR); // Write TSL2561 address status = twi_writebyte (0x80 | addr); // Write command status = twi_start (); // Restart status = twi_writebyte (TSL2561_ADDR | TSL2561_RD); // Write TSL2561 address status = twi_readbyte (c, TW_NACK); // write data twi_stop (); delay_ms (10); return 0; } After the conversion of the integral A / D converter is completed, the corresponding values CH0 and CH1 can be read from the channel 0 register and the channel 1 register, but the unit is Lux (lumens) and the calculation is based on CH0 and CH1. For the TMB package, assuming that the light intensity is E (unit is Lux), the calculation formula is as follows: ① 0 E = 0.030 4 & TImes; CH0-0.062 & TImes; CH0 & TImes; (CH1 / CH0) 1/4 ② 0.50 E = 0.022 4 × CH0-0.031 × CH1 ③ 0.61 E = 0.012 8 × CH0-0.015 3 × CH1 ④ 0.80 E = 0.001 46 × CH0-0.001 12 × CH1 ⑤ CH1 / CH0》 1.30 E = 0 For the CHIPSCALE package, the calculation formula can view the corresponding chip information. 5 Conclusion A system that uses TSL256x to realize real-time monitoring of light intensity has the advantages of high accuracy, low cost, and small size. The chip integrates an integral A / D converter and uses digital signal output, so its anti-interference ability is stronger than similar chips. The chip has been widely used in the field of light intensity monitoring and control.

0 Preface China's urban lighting has been rapidly developed along with the acceleration of China's urbanization process. However, the energy demand and consumption in the development of urban lighting is also increasing. In general, green lighting work still has problems such as high energy consumption, high pollution, and low efficiency. According to the survey, China's current street lamps are mainly low-efficiency lighting, and the energy utilization rate is low. In view of the serious pollution, power waste, high energy density and low lighting efficiency in the lighting, researching the street lamp energy-saving control system and promoting street lighting energy-saving and energy-saving will play an active role in promoting the overall development of green lighting. 1 The current shortage of street lighting systems In modern society, the street lighting of urban charm business cards and windows has created a splendid urban civilization and brought some problems. Energy consumption has become the key to restricting the development of current street lighting systems. 1.1 Large voltage fluctuations - waste of operation Since the change in the grid load varies with the time period, the corresponding voltage fluctuation is also large. In the middle of the night when there are more pedestrians and vehicles, the voltage is lower and the brightness is darker; in the middle of the night, it is extremely bright, which is caused by the voltage rise due to the change of the grid load. Large voltage fluctuations increase the ratio of electricity to heat conversion, reducing the efficiency of the luminaire and causing waste of electrical energy. 1.2 Line loss is large --- line waste The street lamp has a long power supply line and low power, so the line loss is large. At the same time, the general 220 V single-phase voltage-powered street lamp has a serious three-phase unbalance, which will cause excessive zero-sequence current and zero displacement. Increased circuit losses. 1.3 extensive management methods - indirect waste At present, the line control of street lighting is relatively simple, and it is impossible to monitor, record and count the operation results. The discovery of abnormal equipment depends on manual inspection. It is found that the fault is not timely, and the efficiency of handling the fault is not high, which ultimately leads to waste of manpower and material resources. In order to solve the problems existing in the street lamp system, LED street lamps with the advantages of energy saving, environmental protection and longevity have been highly valued by the low carbon society. Research and development of LED street lamp energy-saving control system, improve resource utilization and save energy, has become the top priority of street lamp energy saving. 2 LED street light energy saving control system based on wireless sensing technology The LED street lamp energy-saving control system based on the wireless sensor technology can monitor the switch state of the LED street lamp in real time, and simultaneously detect and collect various parameter information of the LED street lamp. All kinds of parameter information (switch status, current, voltage, brightness, temperature, etc.) of the LED street lamp are transmitted to the monitoring center in real time via the wireless sensor node around the LED street lamp. Based on this, the system designs the maintenance plan and issues an alarm to notify the fault handling, saving labor costs, improving the efficiency of fault handling, and realizing the intelligentization of street lamp management. The LED street lamp energy-saving control system based on wireless sensor technology has the following advantages: 1 wireless mode networking, no wiring, flexible expansion, and no space; 2 easy to adopt, quick and convenient implementation, does not affect the road environment; Convenient, high efficiency of equipment failure processing, reducing the energy consumption of street lamps. The LED street lamp energy-saving control system based on wireless sensing technology improves energy utilization and saves certain energy costs. Extends the life of the lighting fixture while helping the lighting system save a lot of power. 3 overall system design The LED street lamp energy-saving control system based on wireless sensing technology is mainly composed of three parts: monitoring center, sub-network controller and LED street lamp monitor. The system structure is shown in Figure 1. Figure 1 LED street light energy-saving control system based on wireless sensor technology 3.1 LED street light monitor The heart of the LED street light monitor is the microcontroller, which is responsible for data processing and is the data center of the monitor. The voltage, current, and temperature sensors collect current, voltage, and temperature values, and the relay controls the state of the LED street light, and then sends the information to the single-chip microcomputer, and the single-chip microcomputer communicates with the Zigbee RF module to report various parameters of the LED street light to the sub-network controller. Accept the monitoring commands of the subnet controller. The LED street light monitor controls the switching status and acquisition, brightness adjustment, current, temperature, voltage acquisition, and the like. LED street light monitors are divided into external and modular, to meet different needs. The LED street light monitor is shown in Figure 2. Figure 2 LED street light monitor 3.2 Subnet controller design The subnet controller is located between the monitoring center and the LED street light monitor and communicates with the system center and the street light monitor in different ways. It uses the Zigbee communication protocol to issue commands from the system center and feedback the monitoring of the LED street light monitor. The subnet controller is responsible for processing all transactions within this subnet, including monitoring the LED street light monitor operating status and control signals, and handling alarms. The single-chip microcomputer, GPRS/3G and Zigbee RF modules form a subnet controller. The microcontroller is the core of the subnet controller. The MCU receives various commands of the monitoring center and reports the parameter values of the LED street lamp monitor. At the same time, it sends monitoring commands through the Zigbee RF module. 3.3 Monitoring Center The main function of the monitoring center is to monitor and remote data access to the LED street light monitor, including configuration parameters, sending monitoring commands, and collecting LED street lights. The LED street lighting time and switch settings can be changed with the sunshine conditions of the road section and the flow of people and vehicles, which not only meets the needs of lighting, but also saves energy. The function of the monitoring center is implemented by the following modules: Data management module. The data management module is mainly used for data application management and is the core of the whole system. The data management module manages system operation and configuration data, including management of street lamp monitor data, system operation status data, and management of other configuration data. Main interface module. The main interface module is mainly composed of monitoring management, data display and control panel. The data is visually displayed in a graphical manner to provide users with real-time monitoring of the entire LED street light. At the same time, users can configure and manage the system according to their own needs. Database module. The database module is primarily responsible for the data storage and operation of the system. The system can call and play back the historical data stored in the database at any time as needed to provide support for the function execution and analysis of other modules. User management module. The user management module is mainly responsible for the management of user accounts in the system, including account registration, login and modification, setting and authorization of different user rights, strictly controlling user modifications to the system, and achieving system security and stability. Communication management module. The communication management module is mainly responsible for the configuration and management of the communication interface to ensure data communication. It is the external interface of the software system, and through the interaction with the data controlled by the underlying center, the user finally controls the underlying hardware.

The growth of precious flowers, nursery stocks, and back-season vegetables requires natural environmental conditions for growth, including temperature, humidity, light, and carbon dioxide levels. When climatic conditions do not meet the above requirements, they grow poorly, withering, rot or die. If the greenhouse is intelligently controlled so that its climate parameters are always in the optimal state for plant growth, it will greatly increase its output and grade, and bring about better economic benefits. At present, there are few intelligent control applications for agricultural greenhouses in China, mainly because such equipment is expensive and not suitable for national conditions. To this end, we have developed a low-cost plant greenhouse automatic control system that can provide the optimum temperature, humidity, light intensity and carbon dioxide content and other climatic conditions for plant growth, and is most suitable for the existing medium and low grades in China. The "intelligent" transformation of greenhouses is in line with the level of farmers' consumption and is suitable for China's national conditions. Foliar humidity sensors are an important part of the moisture analysis of crop foliage. The function of the sensor subsystem is to convert climate parameters into voltage parameters. It is the main source of information for the monitoring system and relates to the reliability and accuracy of the entire system for detection, data analysis, and control. Mainly include soil moisture sensor, leaf surface humidity sensor, air temperature and humidity integration sensor, light intensity sensor, CO2 sensor. Due to the large area of the greenhouse, the sensor is a fixed-point instrument, so the use of various types of sensors is large. Real-time data collection and processing of leaf surface humidity sensors. In order to ensure real-time detection of environmental changes in the greenhouse, data collection and processing must meet certain time limits so that they can be processed in real time to resist accidents. Most of the functions of the system are realized by software. Since the peripheral circuit is simple, the software can be modified at any time, so the adaptability is strong. The operator can change the preset parameters of the environment according to the habits and growth characteristics of the plants in the greenhouse and ensure the plant growth environment. optimal.