A method and device for controlling drift of a photoelectric tracker

Abstract

The application discloses a kind of photoelectric tracker's control method and device of inhibiting drift, the method includes: setting sampling time interval, every reaches sampling time interval, the motion speed and position of servo system in photoelectric tracker are recorded;The current motion speed of the servo system is obtained;If the current motion speed of the servo system is greater than the first preset threshold, proportion control is carried out to control master order, and the method ends;If the current motion speed of the servo system is compared with the motion speed of the servo system at previous sampling time, the ratio of speed change is less than the second preset threshold, then the servo system enters positioning state;The servo system in positioning state is controlled.The drift phenomenon generated by servo system is obviously improved when multiple systems work simultaneously, and the drift phenomenon of servo system can be effectively inhibited by the application.

Description

Technical Field

[0001] This invention relates to the field of servo control, and more specifically to a control method and apparatus for suppressing drift in a photoelectric tracker. Background Technology

[0002] Tracking systems are widely used in target detection and tracking, such as photoelectric trackers and photoelectric observation and aiming devices. The manual search state of a photoelectric tracker refers to a state where a speed loop, composed of the gyroscope, motor, controller, and load inside the tracker, receives speed signals from an external host computer. These speed signals specify the magnitude and direction of the speed, causing the photoelectric tracker's servo system to move at the specified speed. In the manual search state, only the speed loop is active; this speed loop is a negative feedback loop.

[0003] According to the working principle of the servo system, there are three main electrical factors that cause the optical axis to drift in the manual search state of the photoelectric tracker: the zero position change of the speed sensor (e.g., gyroscope assembly), the zero bias stability of various components of the servo controller, and the zero position change of other electronic components such as the power supply.

[0004] Existing methods for suppressing drift in photoelectric trackers involve zero-point compensation in the servo controller software (typically a DSP) or adjusting the control commands output by the servo controller based on the ambient temperature. For example, if the tracker is used in a cold region at -35°C, or in a hot region at +40°C, zero-point compensation is applied to the control commands output by the servo controller. These control commands are calculated by comparing the control commands issued by the host computer with the data fed back from the gyroscope. While this drift compensation method can control optical axis drift for a standalone servo system, drift still occurs when the servo system is connected to an external device or works in conjunction with other equipment. In such cases, compensation via control commands becomes ineffective. Therefore, a new control method is needed to address the system drift problem caused by multiple systems operating simultaneously in the servo control system. Summary of the Invention

[0005] In view of this, the present invention provides a control method and device for suppressing drift in an optical tracker, which can solve the technical problem of drift in the servo system when multiple systems are working simultaneously. Multiple systems refer to other control systems that work together with the optical tracker, such as: azimuth turntable, inertial components, system controller, etc.

[0006] To solve the above-mentioned technical problems, the present invention is implemented as follows.

[0007] A method for controlling the drift suppression of an optical tracker, comprising:

[0008] Step S1: Set the sampling time interval. At each sampling time interval, record the motion speed and position of the servo system in the photoelectric tracker; obtain the current motion speed of the servo system.

[0009] Step S2: If the current motion speed of the servo system is greater than the first preset threshold, perform proportional control on the control command. The control command is a value used to control the speed of the motor, and the method ends. The control command is used to control the motion speed of the servo system, and the proportional control is to multiply by a proportional coefficient.

[0010] Step S3: If the rate of change of the current motion speed of the servo system compared with the motion speed of the servo system during the previous sampling is less than a second preset threshold, then the servo system enters the positioning state; control the servo system in the positioning state.

[0011] Preferably, a manual search command is obtained, and the servo system of the photoelectric tracker obtains the search speed of the manual search command.

[0012] Preferably, in step S2, the first preset threshold is determined based on the minimum speed value that the servo system can respond to, and the minimum speed value is related to the accuracy of the speed sensor gyroscope configured in the servo system and the control accuracy of the servo controller.

[0013] Preferably, step S3, controlling the servo system that has entered the positioning state, includes:

[0014] Step S31: If the servo system is entering the positioning state for the first time, the integral separation PID control algorithm is used to control the motor, and the method ends; if the servo system is not entering the positioning state for the first time, the position deviation of the servo system is determined, and the position deviation is the deviation of the position of the servo system relative to the position of the servo system at the previous sampling time, and then proceed to step S32.

[0015] Step S32: If the position deviation is less than the first preset angle, the motor is controlled by the integral separation PID control algorithm, and the method ends;

[0016] If the position deviation is greater than the second preset angle, the position deviation is converted into an angle of optical axis offset. After passing through the PD control algorithm, a control quantity for controlling the motor is generated. The motor is then controlled by an integral separation PID control algorithm. The optical axis is the optical axis of the optical device used to display images in the photoelectric tracker. The method ends here.

[0017] If the position deviation is greater than or equal to the first preset angle and less than or equal to the second preset angle, a non-integral separation PID control algorithm is used to generate a control command to control the movement of the motor.

[0018] Preferably, the value of the proportionality coefficient is between 1.00 and 1.30.

[0019] The present invention provides a control device for suppressing drift in a photoelectric tracker, the device comprising:

[0020] Sampling module: configured to set a sampling time interval, and record the motion speed and position of the servo system in the photoelectric tracker at each sampling time interval; obtain the current motion speed of the servo system;

[0021] First control module: configured to perform proportional control on the control command if the current motion speed of the servo system is greater than a first preset threshold, wherein the control command is a value used to control the rotation speed of the motor; the control command is used to control the motion speed of the servo system, and the proportional control is to multiply by a proportional coefficient;

[0022] The second control module is configured to enter a positioning state if the rate of change of the current motion speed of the servo system compared with the motion speed of the servo system during the previous sampling is less than a second preset threshold; and to control the servo system in the positioning state.

[0023] The present invention provides a computer-readable storage medium storing a plurality of instructions; the plurality of instructions are used by a processor to load and execute the method as described above.

[0024] The present invention provides an electronic device, characterized in that the electronic device comprises:

[0025] A processor is used to execute multiple instructions;

[0026] Memory, used to store multiple instructions;

[0027] The plurality of instructions are to be stored in the memory and loaded and executed by the processor as described above.

[0028] Beneficial effects:

[0029] This invention is based on the working principle of servo systems and, according to the basic characteristics of multiple systems working simultaneously, proposes a control method for suppressing drift in photoelectric trackers, which can effectively suppress the drift problem of servo systems when multiple systems are working simultaneously.

[0030] It has the following technical effects:

[0031] (1) When multiple systems work simultaneously, the drift phenomenon generated by the servo system is significantly improved. The present invention can effectively suppress the drift phenomenon of the servo system.

[0032] (2) The control method of the present invention is simple, easy to implement and highly operable.

[0033] (3) The present invention has been verified in photoelectric trackers, with significant effects, and is easy to promote and use. When it is integrated with other external systems, it performs excellently. Attached Figure Description

[0034] Figure 1 A schematic flowchart of the control method for suppressing drift in the photoelectric tracker provided by the present invention;

[0035] Figure 2 This is a schematic diagram of the control device for suppressing drift in the photoelectric tracker provided by the present invention. Detailed Implementation

[0036] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] like Figure 1 As shown, this invention proposes a control method for suppressing drift in a photoelectric tracker, comprising the following steps:

[0038] Step S1: Set the sampling time interval. At each sampling time interval, record the motion speed and position of the servo system in the photoelectric tracker; obtain the current motion speed of the servo system.

[0039] Step S2: If the current motion speed of the servo system is greater than the first preset threshold, perform proportional control on the control command. The control command is a value used to control the speed of the motor, and the method ends. The control command is used to control the motion speed of the servo system, and the proportional control is to multiply by a proportional coefficient.

[0040] Step S3: If the rate of change of the current motion speed of the servo system compared with the motion speed of the servo system during the previous sampling is less than a second preset threshold, then the servo system enters the positioning state; control the servo system in the positioning state.

[0041] In step S1, the following is stated:

[0042] The photoelectric tracker tracks people, vehicles, or other targets. The user determines the target to be tracked. The servo system of the photoelectric tracker includes current loops, speed loops, position loops, and tracking loops. Different loops function in different states of the servo system. Manual search is the process where the user observes objects within the field of view and sends a manual search command via host computer software, instructing the photoelectric tracker to move at a specified speed to search for the target. The manual search command includes information such as search speed and search direction. The manual search state is the process where the speed loop in the servo system is active. After receiving the manual search command, the servo system enters manual search mode. Upon receiving the manual search command, the servo controller within the photoelectric tracker controls the servo system to move at the search speed and search direction specified in the control command.

[0043] Furthermore, step S1 also includes: obtaining a manual search command, wherein the servo system of the photoelectric tracker obtains the search speed of the manual search command; the search speed is sent to the photoelectric tracker by the host computer, and is the final speed value of the speed loop of the photoelectric tracker, which is an evaluation standard.

[0044] In this embodiment, the current motion speed of the servo system is the output value of the servo system speed sensor gyroscope collected by the servo system controller.

[0045] In step S2, the first preset threshold is determined based on the minimum speed value that the servo system can respond to. The minimum speed value is related to the accuracy of the speed sensor gyroscope configured in the servo system and the control accuracy of the servo controller. For example, the first preset threshold is 0.01° / s or 0.02° / s.

[0046] In step S2, proportional control is performed on the control command, where the control command is a numerical value used to indicate the motor speed, wherein:

[0047] Proportional control involves multiplying the control command by a constant coefficient. The resulting control command is then amplified and transmitted to the motor, which in turn drives the servo system.

[0048] Let Econ = K1 * Vex; where Econ is the control command, K1 is the proportional coefficient, and Vex is the speed deviation, which is the difference between the current motion speed of the servo system and the motion speed of the servo system at the previous sampling time.

[0049] Furthermore, the value of K1 is between 1.00 and 1.30. The value of K1 needs to be determined by simulating an initial reference value based on the model of the photoelectric tracker. The initial reference value is then input into the servo controller of the photoelectric tracker, the control effect of the servo system is compared, and then corrections are made to obtain the value of K1 in the actual servo system; typically, K1 is between 1.00 and 1.30.

[0050] Step S3, the purpose of this embodiment is that if the current speed of the servo system changes very little compared to the speed at the previous moment, then the servo system moves at a given speed.

[0051] Step S3 involves controlling the servo system that has entered the positioning state, including:

[0052] Step S31: If the servo system is entering the positioning state for the first time, the integral separation PID control algorithm is used to control the motor, and the method ends; if the servo system is not entering the positioning state for the first time, the position deviation of the servo system is determined, and the position deviation is the deviation of the position of the servo system relative to the position of the servo system at the previous sampling time, and then proceed to step S32.

[0053] Step S32: If the position deviation is less than the first preset angle, the motor is controlled by the integral separation PID control algorithm, and the method ends;

[0054] If the position deviation is greater than the second preset angle, the position deviation is converted into an optical axis offset angle, and a control quantity for controlling the motor is generated through the PD control algorithm. The motor is then controlled using an integral separation PID control algorithm. The optical axis is the optical axis of the optical device used to display images in the photoelectric tracker. The method ends.

[0055] If the position deviation is greater than or equal to the first preset angle and less than or equal to the second preset angle, a non-integral separation PID control algorithm is used to generate a control command to control the movement of the motor.

[0056] In this embodiment, the integral-separated PID control algorithm refers to setting the integral term to zero when the deviation is large or small, and only introducing the integral when the deviation is moderate. The non-integral-separated PID control algorithm is, for example:

[0057]

[0058] Where u(k) is the output signal of the PID controller, which is the control quantity / control command used to control the motor;

[0059] Kp is the proportional gain;

[0060] Ki is the integral coefficient;

[0061] Kd is the differential coefficient;

[0062] e(k) is the velocity deviation, which is the difference between the given velocity value and the gyroscope measurement value.

[0063] PID control algorithm is a control algorithm that combines proportional, integral and derivative functions into one. In essence, it calculates the input deviation value according to the proportional, integral and derivative functional relationship, and the calculation result is used to control the output.

[0064] The present invention also provides an example of a control method for suppressing drift in a photoelectric tracker.

[0065] Taking the control method for suppressing drift when the servo stabilization platform of an optical tracker works in conjunction with multiple systems simultaneously as an example, the specific implementation method is as follows:

[0066] Step 1: When the photoelectric tracker receives a manual search command, and the turntable enters the manual search state, if the movement speed is greater than 0.01° / s, proportional control is used with a proportional coefficient of 1. The control method is as follows:

[0067] Econ = 1 * Vex

[0068] Econ is the control master command;

[0069] K1 is a proportionality coefficient of 1;

[0070] Vex represents the speed deviation;

[0071] Step 2: When the turntable enters manual search mode and the speed remains unchanged, the turntable enters positioning mode;

[0072] The control method after the turntable enters the positioning state is as follows:

[0073] Determine if this is the first time entering the location state.

[0074] If this is the first time entering the positioning state, clear the integral term of the PID control algorithm;

[0075] If this is not the first time entering the positioning state, check the position deviation. If the deviation is less than 0.2 degrees, clear the integral term in the PID control algorithm.

[0076] When the angle deviation is greater than 1 degree, the integral term in the PID control algorithm is cleared; the angle deviation at this time is then processed by the PID control algorithm to generate a control quantity, which is then sent to the motor for control.

[0077] In other cases, the PID control algorithm is used.

[0078] The present invention also provides a control device for suppressing drift in a photoelectric tracker, such as... Figure 2As shown, the device includes:

[0079] Sampling module: configured to set a sampling time interval, and record the motion speed and position of the servo system in the photoelectric tracker at each sampling time interval; obtain the current motion speed of the servo system;

[0080] First control module: configured to perform proportional control on the control command if the current motion speed of the servo system is greater than a first preset threshold, wherein the control command is a value used to control the rotation speed of the motor; the control command is used to control the motion speed of the servo system, and the proportional control is to multiply by a proportional coefficient;

[0081] The second control module is configured to enter a positioning state if the rate of change of the current motion speed of the servo system compared with the motion speed of the servo system during the previous sampling is less than a second preset threshold; and to control the servo system in the positioning state.

[0082] The specific embodiments described above only illustrate the design principles of the present invention. The shapes and names of the components in this description may differ and are not limited. Therefore, those skilled in the art can modify or make equivalent substitutions to the technical solutions described in the foregoing embodiments; and these modifications and substitutions do not depart from the inventive spirit and technical solutions of the present invention, and should all fall within the protection scope of the present invention.

Claims

1. A control method for suppressing drift in a photoelectric tracker, characterized in that, include: Step S1: Set the sampling time interval. At each sampling time interval, record the motion speed and position of the servo system in the photoelectric tracker. Obtain the current motion speed of the servo system; Step S2: If the current motion speed of the servo system is greater than the first preset threshold, perform proportional control on the control command. The control command is a value used to control the speed of the motor, and the method ends. The control command can control the motion speed of the servo system, and the proportional control is to multiply by a proportional coefficient. Step S3: If the rate of change of the current motion speed of the servo system compared with the motion speed of the servo system during the previous sampling is less than the second preset threshold, then the servo system enters the positioning state. Control the servo system that has entered the positioning state; Step S3 involves controlling the servo system that has entered the positioning state, including: Step S31: If the servo system is entering the positioning state for the first time, the integral separation PID control algorithm is used to control the motor, and the method ends; if the servo system is not entering the positioning state for the first time, the position deviation of the servo system is determined, and the position deviation is the deviation of the position of the servo system relative to the position of the servo system at the previous sampling time, and then proceed to step S32. Step S32: If the position deviation is less than the first preset angle, the motor is controlled by the integral separation PID control algorithm, and the method ends; If the position deviation is greater than the second preset angle, the position deviation is converted into an angle of optical axis offset. After passing through the PD control algorithm, a control quantity for controlling the motor is generated. The motor is then controlled by an integral separation PID control algorithm. The optical axis is the optical axis of the optical device used to display images in the photoelectric tracker. The method ends here. If the position deviation is greater than or equal to the first preset angle and less than or equal to the second preset angle, a non-integral separation PID control algorithm is used to generate a control command to control the movement of the motor.

2. The method as described in claim 1, characterized in that, The photoelectric tracker's servo system acquires the search speed of the manual search command.

3. The method as described in any one of claims 1-2, characterized in that, In step S2, the first preset threshold is determined based on the minimum speed value that the servo system can respond to. The minimum speed value is related to the accuracy of the speed sensor gyroscope configured in the servo system and the control accuracy of the servo controller.

4. The method according to any one of claims 1-2, characterized in that, The value of the proportionality coefficient is between 1.00 and 1.

30.

5. A control device for suppressing drift in a photoelectric tracker, used to execute the method according to any one of claims 1-4, characterized in that, The device includes: Sampling module: configured to set a sampling time interval, and record the motion speed and position of the servo system in the photoelectric tracker at each sampling time interval; obtain the current motion speed of the servo system; First control module: configured to perform proportional control on the control command if the current motion speed of the servo system is greater than a first preset threshold, wherein the control command is a value used to control the speed of the motor; the control command can control the motion speed of the servo system, and the proportional control is multiplying by a proportional coefficient; The second control module is configured to enter a positioning state if the rate of change of the current motion speed of the servo system compared with the motion speed of the servo system during the previous sampling is less than a second preset threshold; and to control the servo system in the positioning state.

6. A computer-readable storage medium storing a plurality of instructions; the plurality of instructions being loaded by a processor and executing the method as claimed in any one of claims 1-4.

7. An electronic device, characterized in that, The electronic device includes: A processor is used to execute multiple instructions; Memory, used to store multiple instructions; The plurality of instructions are to be stored in the memory and loaded by the processor and executed as described in any one of claims 1-4.

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