Tray position correction device and method suitable for electric energy meter verification

Abstract

The invention discloses a tray position correction device and method suitable for electric energy meter verification. The device comprises a laser distance measuring sensor group which comprises at least two laser distance measuring sensors symmetrically installed on the left side and the right side of a tray and is used for detecting the distance values from the left side and the right side of the tray to a reference surface in real time; the main control unit is connected with the laser distance measuring sensor group and is used for calculating the inclination angle of the tray according to the distance difference between the left side and the right side and generating a steering engine control signal; and the steering engine driving module is used for receiving the control signal of the main control unit and driving a steering engine to adjust the position of the tray. According to the scheme, multi-sensor fusion control is adopted, laser ranging and a weighing sensor are combined, and double closed-loop control of angle detection and load compensation is achieved. Through dynamic PID parameter adjustment, control parameters are optimized in real time based on the load weight and the gravity center offset, so that the method is applied to the condition that the load and the gravity center are greatly different, and the method is suitable for being compatible with verification assembly lines of different types of electric energy meters.

Description

Technical Field

[0001] The present invention relates to the technical field of automatic verification of electric energy meters, and particularly relates to a tray position correction device and method for an electric energy meter verification production line, which is applicable to real-time adjustment of the posture of a high-precision tray. Background Art

[0002] In an automatic verification production line of electric energy meters, a tray carries the electric energy meters to be inspected and needs to be accurately positioned to complete operations such as crimping and communication. The pin insertion device for detection needs to accurately insert into the interface of the electric energy meter to be verified. Therefore, it is necessary to ensure the accurate position of the tray. Otherwise, it will cause poor contact and affect the verification work or cause damage to components. The existing tray correction technologies mainly rely on restricting the position of the tray through fixed stoppers or guide rails, but they cannot dynamically compensate for mechanical wear or assembly errors. After long-term use, the positioning accuracy is likely to decline, and rigid contact may damage the tray structure. Or through manual auxiliary correction, relying on the operator to visually judge the level of the tray and use a manual adjustment mechanism to correct it, there are problems such as large subjective errors and slow response speed, and it is difficult to meet the requirements of industrial automation.

[0003] Especially for a verification production line that needs to be compatible with different types of electric energy meters, the tray needs to load different types of electric energy meter terminals including single-phase electric energy meters, three-phase electric energy meters, and acquisition terminals. At the same time, in order to cooperate with subsequent crimping and detection operations, the electric energy meter terminals need to be placed on one side of the tray. In this way, there will be significant differences in the load and center of gravity of the tray during use. Therefore, an accurate and efficient technical solution is also needed to perform real-time tray correction every time the tray is loaded. Summary of the Invention

[0004] The present invention is to overcome the above deficiencies of the existing tray correction technologies, and provides a tray position correction device and method applicable to the verification of electric energy meters.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a tray position correction device applicable to the verification of electric energy meters, and the device includes:

[0007] A tray for carrying the electric energy meters to be inspected;

[0008] A servo motor, the servo disc of the servo motor is connected to the tray, and is used to adjust the horizontal angle of the tray;

[0009] A laser ranging sensor group, including at least two laser ranging sensors symmetrically installed on the left and right sides of the tray, and is used to detect the distance values from the left and right sides of the tray to a reference plane in real time;

[0010] The main control unit, connected to the laser ranging sensor group, is used to calculate the tilt angle of the tray according to the distance difference between the left and right sides and generate a servo control signal;

[0011] The servo drive module is used to receive the control signal from the main control unit and drive the servo to adjust the position of the tray;

[0012] The power supply module provides isolated power for the laser ranging sensor group, the main control unit and the servo drive module.

[0013] Preferably, the main control unit includes a TM32F103VCT6 chip.

[0014] Preferably, the laser ranging sensor uses a VL53LX laser ranging sensor.

[0015] The present invention also provides a method for correcting the position of a tray applicable to the verification of electric energy meters. The method includes the following steps:

[0016] Step 1: Synchronously collect the distance values L left and L right from both sides of the tray to the reference plane through laser ranging sensors symmetrically installed on the left and right sides of the tray, and the sampling time difference is less than 1m;

[0017] Step 2: Calculate the height difference Δh = L left -L right , and determine the tilt angle θ of the tray according to the formula , where D is the horizontal distance between the two sensors;

[0018] Step 3: If |θ| > θ max , trigger an emergency stop and alarm; if |θ| < θ deadzone , determine that the tray is horizontal; otherwise, execute Step 4;

[0019] Step 4: Generate a servo control signal based on the PID control algorithm:

[0020] Calculate the angle deviation e(t) = -θ, e(t) = θ target -θ current as the angle deviation;

[0021] Execute the PID operation and limit the integral term, where u(t) is the servo control amount, e(t) = θ target -θ current is the angle deviation, θ target is the target angle, θ target = 0, θ current is the current angle, K P 、K i 、K dThey are the proportional, integral, and derivative coefficients respectively;

[0022] Convert u(t) into a servo drive signal and send it to the servo through the isolated R485 bus;

[0023] Step 5, the servo drives the tray to adjust the position, and returns 1 until |θ| < θ deadzone .

[0024] Preferably, the PID parameters K P , K i , K d are tuned by the Ziegler-Nichol critical proportional method and satisfy K i ≤0.2K P .

[0025] Preferably, in step 1, the laser ranging data needs to be processed by moving average filtering, and the filtering formula is:

[0026] Preferably, in step 4, the integral term limiting range is ±0.2u max , where u max is the maximum control amount of the servo.

[0027] Preferably, the emergency stop threshold θ max = 1°, and the dead zone threshold θ deadzone = 0.1°.

[0028] Preferably, load cells are also provided at the four corners of the tray in step 1 to obtain the force parameters F1, F2, F3, and F4 respectively, and the total load weight F of the tray is obtained as F = F1 + F2 + F3 + F4;

[0029] Step 4 further includes:

[0030] Step 401, calculate the angle deviation e(t) = -θ, e(t) = θ target -θ current is the angle deviation;

[0031] Step 402, dynamically adjust the PID control parameters K c , K p , K i , K d according to the load weight F and the center of gravity x i , F i +1] corresponding reference PID parameters K p0 , K i0 , K d0 ,

[0032] Step 403: The length of the tray is L, the width is W, the center is the origin (0, 0), and the center of gravity coordinates are set as (x c , y c ). According to the obtained force parameters F1, F2, F3, and F4 respectively,

[0033] The total moment of the tray about the X-axis The total moment about the Y-axis Calculate the servo to adjust the tilt direction of the tray, that is, about the Y-axis direction, x c The center of gravity offset Δx = x c -x nominal , where

[0034] Calculate the center of gravity offset Δx = x c -x nominal Calculate the parameter compensation coefficient, where L is the length of the tray, and α, β are calibration constants.

[0035] Preferably, in step 402, the weight-parameter mapping table is generated by offline calibration. The specific steps include:

[0036] Step 4021: Apply the nominal load F nominal on the tray and adjust the center of gravity to the center position to calibrate the reference parameters K p0 , K i0 , K d0 ;

[0037] Step 4022: Increase the load in steps of 10%F nominal to F max , and record the optimal PID parameters under each load;

[0038] Step 4023: For each load F i , offset the center of gravity ±20%L along the length direction of the tray to fit the α, β coefficients.

[0039] It is necessary to be compatible with the verification production lines for different types of electric energy meters. The tray needs to load different types of electric energy meter terminals including single-phase electric energy meters, three-phase electric energy meters, and acquisition terminals. At the same time, in order to cooperate with subsequent crimping and detection operations, the electric energy meter terminals need to be placed on one side of the tray. In this way, the load and the center of gravity of the tray during use will be quite different, so it is necessary to calibrate the tray in a timely manner.

[0040] This solution adopts multi-sensor fusion control: combining laser ranging with a weighing sensor to achieve dual closed-loop control of angle detection and load compensation. By dynamically adjusting the PID parameters, the control parameters are optimized in real time based on the load weight and the center-of-gravity offset, so as to be applicable to situations where there are significant differences in both the load and the center of gravity, and it is suitable for being compatible with the verification production lines for different types of electricity meters. Description of the Drawings

[0041] Figure 1 is the circuit diagram of the main control unit of a tray position correction device applicable to the verification of electricity meters;

[0042] Figure 2 is the circuit diagram of the laser ranging sensor;

[0043] Figure 3 is the circuit diagram of the power supply module;

[0044] Figure 4 is the circuit diagram of the servo communication circuit;

[0045] Figure 5 is the principle block diagram of a tray position correction device applicable to the verification of electricity meters. Detailed Implementation Manner

[0046] The present invention will be further described below in conjunction with the drawings and the detailed implementation manner.

[0047] The embodiment of the present application provides a tray position correction device applicable to the verification of electricity meters, and the device includes:

[0048] A tray for carrying the electricity meter to be verified;

[0049] A servo, the servo disk of which is connected to the tray and is used to adjust the horizontal angle of the tray;

[0050] A laser ranging sensor group, including at least two laser ranging sensors symmetrically installed on the left and right sides of the tray, and is used to detect the distance values from the left and right sides of the tray to the reference plane in real time;

[0051] A main control unit, connected to the laser ranging sensor group, and is used to calculate the tilt angle of the tray according to the distance difference between the left and right sides and generate a servo control signal;

[0052] A servo drive module, which is used to receive the control signal of the main control unit and drive the servo to adjust the tray position;

[0053] A power supply module, which provides an isolated power supply for the laser ranging sensor group, the main control unit and the servo drive module;

[0054] The main control unit dynamically adjusts the output of the servo through the PID control algorithm until the tilt angle of the tray is less than the set threshold.

[0055] The described main control unit includes a TM32F103VCT6 chip.

[0056] The described laser ranging sensor uses a VL53LX laser ranging sensor.

[0057] The basic principle of this solution is as follows: Two laser ranging sensors placed on both sides of the tray are used to determine whether the tray is tilted. If the tray is placed completely straight, the laser sensors on both sides should be a preset fixed value, and the values on both sides are the same. If there is a tilt, it is determined whether the tray tilts to the left or the right based on the difference in distances on both sides; the servo motor connected to the tray starts to adjust the angle and stops when the position of the tray is adjusted to meet the requirements. At this time, the crimping starts.

[0058] As Figure 1 shown, the circuit diagram of the main control unit

[0059] The main control part consists of an STM32F103VCT6 chip U1; a connector J2; resistors R1, R2, R3; capacitors C1, C2, C3, C13, C14; crystal oscillators E1, E2; and an LED lamp ELD1.

[0060] The twentieth pin, nineteenth pin, twenty-seventh pin, ninety-ninth pin, seventy-fourth pin, forty-ninth pin, and nineteenth pin of chip U1 are connected to network GND; the sixty-eighth pin of chip U1 is connected to network TX1, and the sixty-ninth pin is connected to network RX1; the ninety-second pin is connected to network SCL_EXT, and the ninety-third pin is connected to network SDA_EXT; one end of resistor R3 is connected to the fifth pin of chip U1, to network PE6, and the other end is connected to the positive electrode of LED lamp LED1, and the negative electrode of LED1 is connected to GND; one end of capacitor C1 is connected to crystal oscillator E1, to network XT1, and the other end is connected to GND; one end of capacitor C2 is connected to crystal oscillator E1, to network XT2, and the other end is connected to GND; one end of capacitor C3 is connected to crystal oscillator E2, to network X1, and the other end is connected to GND; one end of capacitor C13 is connected to crystal oscillator E2, to network X2, and the other end is connected to GND; one end of crystal oscillator E1 is connected to network XT1, to the twelfth pin of chip U1, and the other end is connected to network XT2, to the thirteenth pin of chip U1; one end of crystal oscillator E2 is connected to network X1, to the eighth pin of chip U1, and the other end is connected to network X2, to the ninth pin of chip U1; one end of resistor R1 is connected to GND, and the other end is connected to the ninety-fourth pin of chip U1, to network BOOT0; one end of capacitor C4 is connected to GND, and the other end is connected to the fourteenth pin of chip U1; one end of resistor R2 is connected to the fourteenth pin of chip U1, and the other end is connected to 3V3; the first pin and the second pin of connector J2 are connected to 3V3, the third pin of connector J2 is connected to the ninetieth pin of chip U1, to network NJTRST; the fourth pin of connector J2 is connected to network RST, to the fourteenth pin of chip U1, the fifth pin of connector J2 is connected to network JTDI, to the seventy-seventh pin of chip U1; the sixth pin of connector J2 is connected to network JTDO, to the eighty-ninth pin of chip U1; the seventh pin of connector J2 is connected to network JTMS, to the seventy-second pin of chip U1; the eighth pin of connector J2 is left floating; the ninth pin of connector J2 is connected to network JTCK, to the seventy-sixth pin of chip U1; the tenth pin of connector J2 is connected to GND.

[0061] As Figure 2 shown is the circuit diagram of the laser ranging sensor

[0062] The sensor drive circuit consists of VL53LX chips U4, U6 and NDC7002N chips U3, U5; resistors R5, R6, R8, R9, R10, R11, R12, R13, R45, R15, R16, R17, capacitors C24, C25.

[0063] The first pin and the eleventh pin of chip U4 are connected to 3V3, and the second pin, the third pin, the fourth pin, the sixth pin, and the twelfth pin are connected to GND. One end of capacitor C24 is connected to the first pin of chip U4, which is connected to 3V3, and the other end is connected to the second pin of the chip, which is connected to GND; one end of resistor R8 is connected to 3V3, and the other end is connected to the fifth pin of chip U4; one end of resistor R9 is connected to 3V3, and the other end is connected to the seventh pin of chip U4; the ninth pin of chip U4 is connected to the second pin of chip U3, which is connected to the SDA network; the tenth pin of chip U4 is connected to the fifth pin of chip U3, which is connected to the SCL network. One end of resistor R10 is connected to the second pin of chip U3, and the other end is connected to 3V3; one end of resistor R5 is connected to 3V3, and the other end is connected to the fifth pin of chip U3; one end of resistor R6 is connected to +5V, and the other end is connected to the sixth pin of chip U3, which is connected to the SCL_EXT network; one end of resistor R11 is connected to +5V, and the other end is connected to the fourth pin of chip U3, which is connected to the SDA_EXT network.

[0064] The first pin and the eleventh pin of chip U6 are connected to 3V3, and the second pin, the third pin, the fourth pin, the sixth pin, and the twelfth pin are connected to GND. One end of capacitor C25 is connected to the first pin of chip U6, which is connected to 3V3, and the other end is connected to the second pin of the chip, which is connected to GND; one end of resistor R14 is connected to 3V3, and the other end is connected to the fifth pin of chip U6; one end of resistor R15 is connected to 3V3, and the other end is connected to the seventh pin of chip U6; the ninth pin of chip U6 is connected to the second pin of chip U5, which is connected to the SDA network; the tenth pin of chip U6 is connected to the fifth pin of chip U5, which is connected to the SCL network. One end of resistor R16 is connected to the second pin of chip U5, and the other end is connected to 3V3; one end of resistor R12 is connected to 3V3, and the other end is connected to the fifth pin of chip U5; one end of resistor R13 is connected to +5V, and the other end is connected to the sixth pin of chip U5, which is connected to the SCL_EXT network; one end of resistor R17 is connected to +5V, and the other end is connected to the fourth pin of chip U5, which is connected to the SDA_EXT network.

[0065] As Figure 3 is the circuit diagram of the power supply module.

[0066] The power supply circuit consists of connector J1, power supply module M1; chip U2; DC / DC module DC1; capacitors C4, C5, C6, C7, C8, C9, C10, C11, C12, C15, C16, C17, C18, C19, C20, C21, C22, C23

[0067] The first pin of connector J1 is connected to 12VG, and the third pin is connected to +12V; the positive electrode of capacitor C4 is connected to +12V, and the negative electrode is connected to 12VG; one end of capacitor C5 is connected to +12V, and the other end is connected to 12VG; the twenty-second and twenty-third pins of power module M1 are connected to +12V, the second and third pins are connected to 12VG, the fourteenth pin is connected to +5V, and the sixteenth pin is connected to GND; the positive electrode of capacitor C6 is connected to +5V, and the negative electrode is connected to GND, one end of capacitor C7 is connected to +5V, and the other end is connected to GND; one end of capacitor C8 is connected to +5V, and the other end is connected to GND, the third pin of chip U2 is connected to +5V, the first pin is connected to GND, and the second and fourth pins are connected to 3V3; one end of capacitor C10 is connected to 3V3, and the other end is connected to GND; the positive electrode of capacitor C9 is connected to 3V3, and the negative electrode is connected to GND; one end of capacitor C11 is connected to 3V3, and the other end is connected to GND, one end of capacitor C12 is connected to 3V3, and the other end is connected to GND; one end of capacitor C15 is connected to +5V, and the other end is connected to GND; one end of capacitor C16 is connected to +5V, and the other end is connected to GND; one end of capacitor C17 is connected to +5V, and the other end is connected to GND; one end of capacitor C18 is connected to +5V, and the other end is connected to GND; one end of capacitor C19 is connected to +5V, and the other end is connected to GND; the positive electrode of capacitor C20 is connected to +5V, and the negative electrode is connected to GND; the first pin of DC / DC module DC1 is connected to +5V, the second pin is connected to GND, the third pin is connected to GL_5V, and the fifth pin is connected to GL_GND; the positive electrode of capacitor C21 is connected to GL_5V, and the negative electrode is connected to GL_GND; one end of capacitor C22 is connected to GL_5V, and the negative electrode is connected to GL_GND; one end of capacitor C23 is connected to GL_5V, and the negative electrode is connected to GL_GND.

[0068] Figure 4 It is the circuit diagram of the servo communication circuit.

[0069] The servo communication circuit consists of chip US1; connector J3; LED lights LED2, LED3; resistors R4, R7, RS1, RS2, RS3, RS4, RS5, RS6, RS7, RS8, RS9, RT1, RT2; triode Q1; optocouplers QS1, QS2

[0070] The positive electrode of the LED lamp LED1 is connected to 3V3, the negative electrode is connected to the resistor R4, and the other end of the resistor R4 is connected to the RX1 network; the positive electrode of the LED lamp LED2 is connected to 3V3, the negative electrode is connected to the resistor R7, and the other end of the resistor R7 is connected to the TX1 network; one end of the resistor RS1 is connected to 3V3, and the other end is connected to the RX1 network; the collector of the triode Q1 is connected to the RX1 network, the emitter is connected to GND, one end of the resistor RS2 is connected to the third pin of the optocoupler QS1, and the other end is connected to the base of the triode Q1; one end of the resistor RS4 is connected to the third pin of the optocoupler QS1, and the other end is connected to GND; the first pin of the optocoupler QS1 is connected to GL_5V, the fourth pin is connected to 3V3, the second pin is connected to the resistor RS5, and the other end of the resistor RS5 is connected to the first pin of the chip US1; one end of the resistor RS8 is connected to the TX1 network, and the other end is connected to the second pin of the optocoupler QS2. One end of the resistor RS6 is connected to the first pin of the optocoupler QS2, and the other end is connected to the second pin of the optocoupler QS2. The first pin of the optocoupler QS2 is connected to 3V3, the fourth pin of the optocoupler QS2 is connected to GL_5V, and the third pin of the optocoupler QS2 is connected to the second and third pins of the chip QS1; one end of the resistor RS9 is connected to the third pin of the optocoupler QS2, and the other end is connected to GL_GND; one end of the resistor RS3 is connected to GL_GND, and the other end is connected to the seventh pin of the chip US1; one end of the resistor RT1 is connected to the seventh pin of the chip US1, and the other end is connected to the 485B network; one end of the resistor RS7 is connected to the sixth pin of the chip US1, and the other end is connected to GL_5V; one end of the resistor RT2 is connected to the sixth pin of the chip US1, and the other end is connected to the 485A network; the fourth pin of the chip US1 is connected to GL_GND, the eighth pin is connected to GL_5V, and the fifth pin is connected to GL_GND. The first pin of the connector J3 is connected to 12VG. The second pin is connected to +12V, the third pin is connected to 485A, and the fourth pin is connected to 485B.

[0071] In the embodiment of the present application, the method for correcting the servo control tray is further optimized, and at the same time, a method for correcting the tray position applicable to the verification of the electric energy meter is provided. The method includes the following steps:

[0072] Step 1, synchronously collect the distance values L left and L right from both sides of the tray to the reference plane through the laser ranging sensors symmetrically installed on the left and right sides of the tray, and the sampling time difference is less than 1m;

[0073] Step 2, calculate the height difference Δh = L left -L right , and determine the tilt angle θ of the tray according to the formula , where D is the horizontal distance between the two sensors;

[0074] Step 3, if |θ| > θ max , trigger an emergency stop and alarm; if |θ| < θ deadzone , determine that the tray is horizontal; otherwise, execute step 4;

[0075] Step 4, generate the servo control signal based on the PID control algorithm:

[0076] Calculate the angle deviation e(t) = -θ, e(t) = θ target -θ current is the angle deviation;

[0077] Execute the PID operation and limit the amplitude of the integral term, where u(t) is the servo control quantity, e(t) = θ target -θ current is the angle deviation, θ target is the target angle, θ target = 0, θ current is the current angle, K P 、K i 、K d are the proportional, integral, and differential coefficients respectively;

[0078] Convert u(t) into a servo drive signal and send it to the servo through the isolated R485 bus;

[0079] Step 5, the servo drives the tray to adjust the position, and returns 1 until |θ| < θ deadzone .

[0080] Preferably, the PID parameters K P 、K i 、K d are tuned by the Ziegler-Nichol critical ratio method and satisfy K i ≤ 0.2K P .

[0081] Preferably, in the said Step 1, the laser ranging data needs to be processed by moving average filtering, and the filtering formula is:

[0082] Preferably, in the said Step 4, the integral term amplitude limiting range is ±0.2u max , where u max is the maximum control quantity of the servo.

[0083] Preferably, the emergency stop threshold θ max = 1°, and the dead zone threshold θ deadzone = 0.1°.

[0084] Preferably, a weighing sensor group is further provided at the four corners of the tray in step 1 to obtain the force parameters F1, F2, F3, and F4 respectively, and the total load weight F of the tray is obtained as F = F1 + F2 + F3 + F4. The installation method of the weighing sensor group here is that a connecting plate can be set between the tray and the servo motor. The connecting plate is parallel to the tray and located below the tray, and has a buffer connecting member (such as a rubber pad, etc.) that can move up and down with the tray. The weighing sensor group is set between the tray and the connecting plate and below the four corners of the tray. In this way, it can not only meet the linkage structure of the servo motor driving and adjusting the tray, but also meet the real-time monitoring of the tray load situation by the weighing sensor group.

[0085] The said step 4 further includes:

[0086] Step 401, calculate the angle deviation e(t) = -θ, e(t) = θ target -θ current is the angle deviation;

[0087] Step 402, according to the load weight F and the center of gravity x c , dynamically adjust the PID control parameters K p , K i , K d , preset a weight-parameter mapping table, which includes the reference PID parameters K i , F i +1] corresponding to different load intervals [F p0 , K i0 , K d0 ,

[0088] Step 403, the length of the tray is L, the width is W, the center is the origin (0,0), and the center of gravity coordinates are set as (x c , y c ). According to the force parameters F1, F2, F3, and F4 obtained respectively,

[0089] The total torque of the tray in the X-axis direction The total torque around the Y-axis Calculate the direction in which the servo motor adjusts the tilt of the tray, that is, the direction around the Y-axis, x c The center of gravity offset Δx = x c -x nominal , where

[0090] Calculate the center of gravity offset Δx = x c -x nominal Calculate the parameter compensation coefficient, where L is the length of the tray, and α, β are calibration constants.

[0091] Preferably, in step 402, the weight-parameter mapping table is generated through off-line calibration. The specific steps include:

[0092] Step 4021: Apply a nominal load F on the tray nominal and adjust the center of gravity to the center position to calibrate the reference parameters K p0 、K i0 、K d0 ;

[0093] Step 4022: Increase the load in steps of 10%F nominal to F max , and record the optimal PID parameters under each load;

[0094] Step 4023: For each load F i , offset the center of gravity by ±20%L along the length direction of the tray, and fit to obtain the α and β coefficients.

[0095] This solution is especially for the verification production line that needs to be compatible with different types of electric energy meters. The tray needs to load different types of electric energy meter terminals including single-phase electric energy meters, three-phase electric energy meters and acquisition terminals, etc. At the same time, in order to cooperate with subsequent crimping and detection operations, the electric energy meter terminals need to be placed on one side of the tray. In this way, there will be great differences in the load and the center of gravity during the use of the tray. Therefore, it is difficult to adapt to the load change with static PID parameters, resulting in overshoot or slow response in adjustment; lacking a center of gravity offset compensation mechanism, the calibration accuracy decreases when the load distribution is uneven.

[0096] The main innovation of this solution lies in:

[0097] (4) Multi-sensor fusion control: Combine laser ranging with a weighing sensor to achieve double closed-loop control of angle detection and load compensation.

[0098] (5) Dynamic PID parameter adjustment: Optimize the control parameters in real time based on the load weight and the center of gravity offset, breaking through the limitations of traditional fixed PID parameters. Calculate the center of gravity position through a weighing sensor, and dynamically adjust the PID parameters to adapt to different load distribution scenarios. Calibrate the parameter mapping table, and optimize the PID parameters offline according to the load weight and the center of gravity offset to ensure control consistency.

[0099] (6) Emergency classification and handling mechanism: Balance the response speed and safety through tilt angle threshold determination and dead zone design.

Claims

1. A tray position correction device applicable to the verification of electric energy meters, characterized in that The device includes: A tray for carrying the electricity meter to be inspected; A servo motor, the steering wheel of which is connected to the tray for adjusting the horizontal angle of the tray; A laser ranging sensor group including at least two laser ranging sensors symmetrically installed on the left and right sides of the tray for detecting the distance values from the left and right sides of the tray to the reference plane in real time; A main control unit connected to the laser ranging sensor group for calculating the tilt angle of the tray according to the distance difference between the left and right sides and generating a servo control signal; A servo driver module for receiving the control signal of the main control unit and driving the servo motor to adjust the position of the tray; a power supply module for providing isolated power for the laser ranging sensor group, the main control unit and the servo driver module.

2. The pallet position correction device applicable to the verification of electric energy meters according to claim 1, characterized in that, The main control unit includes a TM32F103VCT6 chip.

3. The pallet position correction device applicable to the verification of electric energy meters according to claim 1 is characterized in that, The laser ranging sensor uses a VL53LX laser ranging sensor.

4. A tray position correction method applicable to the verification of electric energy meters, characterized in that The method includes the following steps: Step 1: Synchronously collect the distance values L from both sides of the tray to the reference plane through laser ranging sensors symmetrically installed on the left and right sides of the tray. left and L right , with a sampling time difference less than 1 ms. Step 2, calculate the height difference Δh = L left -L right , and determine the tray tilt angle θ according to the formula , where D is the horizontal distance between the two sensors; Step 3, if ∣θ∣>θ max , trigger emergency shutdown and alarm; if ∣θ∣<θ deadzone , determine that the tray is horizontal; otherwise, execute Step 4; Step 4, generating a servo control signal based on the PID control algorithm: Calculate the angular deviation e(t) = -θ, e(t) = θ target -θ current where θ is the angular deviation; Perform PID operation And limit the integral term, where u(t) is the servo control quantity, and e(t) = θ target - θ current Is the angle deviation, θ target Is the target angle, θ target = 0, θ current Is the current angle, K P , K i , K d Are the proportional, integral, and differential coefficients respectively; Converting u(t) into a servo drive signal and sending it to the servo motor through the isolated R485 bus; Step 5, the servo drives the tray to adjust the position, and returns 1 until |θ| < θ deadzone .

5. A pallet position correction method applicable to the verification of electric energy meters according to claim 4, characterized in that, The PID parameters K P , K i , K d , are tuned by the Ziegler-Nichol critical ratio method and satisfy K i ≤0.2K P .

6. A tray position correction method applicable to the verification of electric energy meters according to claim 4, characterized in that In the above step 1, the laser ranging data needs to be processed by moving average filtering, and the filtering formula is:

7. A method for correcting the position of a tray applicable to the verification of electric energy meters according to claim 4, characterized in that, In the said step 4, the integral term limiting range is ±0.2u max , where u max is the maximum control amount of the steering gear.

8. A tray position correction method applicable to the verification of electric energy meters according to claim 4, characterized in that, The emergency shutdown threshold θ max = 1°, and the dead zone threshold θ deadzone = 0.1°.

9. A method for correcting the position of a tray applicable to the verification of electric energy meters according to claim 4, characterized in that, In step 1, a weighing sensor group is further arranged at the four corners of the tray to respectively obtain the force parameters F1, F2, F3, and F4, and the total load weight of the tray F = F1 + F2 + F3 + F4 is obtained; Step 4 further includes: Step 401, calculate the angular deviation e(t) = -θ, e(t) = θ target -θ current is the angular deviation; Step 402: Dynamically adjust the PID control parameters K c , K p , and K i according to the load weight F and the center of gravity x. A preset weight-parameter mapping table is included, which contains the reference PID parameters K d , K i , and K i corresponding to different load intervals [F p0 , F i0 + 1]. d0 ​ Step 403, the length of the tray is L, the width is W, the center is the origin (0, 0), and the center of gravity coordinates are set as (x c , y c ). According to the obtained force parameters F1, F2, F3, and F4 respectively, Total moment of the tray in the X-axis direction Total moment about the Y-axis Calculate the direction in which the servo adjusts the tilt of the tray, that is, about the Y-axis, x c Center of gravity offset Δx = x c -x nominal , where Calculate the center of gravity offset Δx of the steering gear adjustment tray in the tilting direction, where Δx = x c - x nominal Calculate the parameter compensation coefficient where L is the tray length, and α, β are calibration constants 10. A tray position correction method applicable to the verification of electric energy meters according to claim 9, characterized in that, In step 402, the weight-parameter mapping table is generated through offline calibration, and the specific steps include: Step 4021, apply a nominal load F on the tray nominal and adjust the center of gravity to the center position to calibrate the reference parameter K p0 , K i0 , K d0 ; Step 4022, increase the load in steps of 10% of F nominal until it reaches F max , and record the optimal PID parameters at each load; Step 4023, for each load F i , offset the center of gravity by ±20%L along the length direction of the tray, and fit to obtain the α and β coefficients.

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