Two-dimensional turntable capable of realizing self-adaptive high-precision tracking and control method thereof

Abstract

The invention provides a two-dimensional turntable capable of realizing self-adaptive high-precision tracking and a control method thereof, relates to a photoelectric tracking two-dimensional turntable and a control method thereof, and is used for solving the technical problems that an existing two-dimensional turntable high-precision tracking system is poor in environmental adaptability and meets the requirement of high-precision tracking in a large-speed span range. By establishing a parameter identification model, when the two-dimensional turntable is influenced by factors such as temperature, azimuth angle and pitch angle, parameter identification is carried out on changes of wire winding torque, friction torque and rotational inertia, and control parameters are automatically changed through parameter identification, so that the control precision is improved. Ground tests prove that the method can realize high-precision tracking in a large-span speed range.

Description

Technical Field

[0001] The invention relates to a photoelectric tracking two-dimensional turntable and a control method, and in particular to a two-dimensional turntable capable of realizing adaptive high-precision tracking and a control method thereof. Background Art

[0002] With the advancement of science and technology, the requirements for the tracking accuracy of two-dimensional turntables are getting higher and higher. High-precision tracking means that the two-dimensional turntable is more sensitive to changes in friction torque, winding torque and moment of inertia, resulting in reduced parameter robustness (the ability of the system to survive abnormal and dangerous situations). A set of parameters often cannot meet the requirements of high-precision tracking under large speed spans.

[0003] The traditional control method of the photoelectric two-dimensional turntable (PID classic control method) can compensate for the random changes of the winding torque and friction torque during the turntable movement to a certain extent, but the adaptability to the speed is narrow and the environmental adaptability is poor. Affected by temperature and other factors, when the winding torque and friction torque change greatly, the control parameters need to be changed according to the changes. In order to achieve high-precision tracking, it is generally necessary to readjust the control parameters when the temperature changes greatly within one day or the next day. Since it is impossible to adjust the parameters online in real time, it not only increases the difficulty of work, but also seriously affects the progress of the test. Therefore, the environmental adaptability of the high-precision tracking system of the two-dimensional turntable is low. It can be seen that the traditional control method used by the two-dimensional turntable has poor robustness and adaptability, and cannot meet the requirements of high-precision tracking within a large speed span. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problems that the existing two-dimensional turntable high-precision tracking system has poor environmental adaptability and a single control parameter cannot meet the requirements of high-precision tracking within a large speed span, and to propose a two-dimensional turntable and a control method thereof that can realize adaptive high-precision tracking.

[0005] To solve the above technical problems, the technical solutions provided by the present invention are as follows:

[0006] A two-dimensional turntable capable of realizing adaptive high-precision tracking comprises a turntable, a turntable motor connected to an input end of the turntable and controlled by current, an angle measuring unit connected to an angle output end of the turntable, a speed loop located in an inner ring connected to the angle measuring unit, a position loop located in an outer ring, and a disturbance loop located outside the position loop connected to a disturbance output end of the turntable; the speed loop comprises a speed control algorithm unit; the position loop comprises a position control algorithm unit; the angle measuring unit is used to measure the azimuth angle and the pitch angle of the turntable; and the special features thereof are:

[0007] It also includes a control parameter testing system, which includes a state observation unit, a parameter identification unit, a position adaptive controller, and a speed adaptive controller;

[0008] The state observation unit is connected to the state output terminal of the turntable, the angle measuring unit transmits the measured azimuth and pitch angle to the state observation unit, and the state observation unit outputs the temperature of the turntable, as well as the azimuth and pitch angle data, and sends them to the parameter identification unit;

[0009] The parameter identification unit calculates the winding torque, friction torque and moment of inertia according to the temperature, azimuth angle and pitch angle output by the state observation unit; the output end of the parameter identification unit is connected to the input end of the position adaptive controller and the speed adaptive controller respectively;

[0010] The position adaptive controller calculates the corresponding position loop PID gain parameters according to the winding torque, friction torque and rotational inertia output by the parameter identification unit at different temperatures, azimuth angles and pitch angles of the turntable, and sends them to the position control algorithm unit;

[0011] The speed adaptive controller calculates the corresponding speed loop PID gain parameters according to the winding torque, friction torque and rotational inertia output by the parameter identification unit at different temperatures, azimuth angles and pitch angles of the turntable, and sends them to the speed control algorithm unit;

[0012] The position control algorithm unit establishes a position control algorithm for the corresponding stage under the corresponding temperature, azimuth angle, and pitch angle according to the azimuth angle error dA or the pitch angle error dE and the position loop PID gain parameter, and outputs the azimuth angle rate error dωA or the pitch angle rate error dωE;

[0013] The speed control algorithm unit establishes a speed control algorithm for the corresponding stage under the corresponding temperature, azimuth angle and pitch angle according to the azimuth rate error dωA or the pitch rate error dωE output by the position control algorithm and the speed loop PID gain parameter;

[0014] The azimuth error dA is the difference between the target value of the azimuth external guidance target angle input from the turntable and corrected by the disturbance correction algorithm and the azimuth measurement value obtained by the angle measurement unit;

[0015] The pitch angle error dE is the difference between the target value of the pitch angle external guidance target angle input from the turntable after being corrected by the disturbance correction algorithm and the pitch angle measurement value obtained by the angle measurement unit.

[0016] A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking is characterized in that it comprises the following steps:

[0017] 1) Establishing a parameter identification model; the parameter identification model includes a winding torque parameter identification model, a friction torque parameter identification model and a moment of inertia parameter identification model, and the parameter identification unit calculates the winding torque, friction torque and moment of inertia according to the parameter identification model, wherein:

[0018] The steps for establishing the winding torque parameter identification model are as follows:

[0019] a1) The turntable measures the winding torque at different temperatures at the same azimuth and elevation angles to generate a temperature-winding torque variation curve;

[0020] a2) The turntable measures the winding torque at different temperatures at the same azimuth and different pitch angles, and generates a pitch angle, temperature-winding torque variation curve;

[0021] a3) The turntable measures the winding torque at different temperatures at different azimuth angles and the same pitch angle, and generates the azimuth angle, temperature-winding torque variation curve;

[0022] a4) obtaining a winding torque parameter identification model according to the variation curves generated in steps a1 to a3;

[0023] The steps for establishing the friction torque parameter identification model are as follows:

[0024] b1) When the azimuth and elevation angles of the turntable are at the extreme positions, measure the friction torque at different temperatures and generate the temperature-friction torque variation curve at the extreme position;

[0025] b2) When the azimuth angle and the pitch angle of the turntable are both at the middle position, the friction torque at different temperatures is measured to generate a temperature-friction torque variation curve at the middle position;

[0026] b3) obtaining a friction torque parameter identification model according to the variation curves generated in step b1 and step b2;

[0027] The steps to establish the moment of inertia parameter identification model are as follows:

[0028] c1) The turntable measures the moment of inertia at different pitch angles at the same azimuth angle, and generates a pitch angle-moment of inertia variation curve;

[0029] c2) The turntable measures the moment of inertia at different azimuth angles at the same pitch angle, and generates the azimuth-moment of inertia change curve;

[0030] c3) obtaining a moment of inertia parameter identification model according to the change curves generated in step c1 and step c2;

[0031] 2) Based on the parameter identification model obtained in step 1, the position adaptive controller and the speed adaptive controller calculate the PID gain parameters kp, ki, and kd of the position loop and the speed loop respectively according to the changes in the temperature T, azimuth angle A, and pitch angle E of the turntable;

[0032] 3) According to the azimuth error dA or the pitch angle error dE and the PID gain parameters obtained in step 2, the control parameters are confirmed in stages, and the position loop and the speed loop establish the position control algorithm and the speed control algorithm of the corresponding tracking stage. The tracking stage includes the tracking capture stage, the tracking intermediate stage and the tracking holding stage:

[0033] 3.1) In the tracking and capturing stage, according to the target value of the tracking and capturing stage, based on the PID gain parameters kp, ki, and kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm of the tracking and capturing stage are established, and the control parameters kp1, ki1, and kd1 of the position loop and the speed loop in the tracking and capturing stage are calculated respectively;

[0034] 3.2) In the intermediate tracking stage, according to the target value in the intermediate tracking stage, based on the PID gain parameters kp, ki, kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm in the intermediate tracking stage are established, and the control parameters kp2, ki2, kd2 of the position loop and the speed loop in the intermediate tracking stage are calculated respectively;

[0035] 3.3) In the tracking and holding stage, according to the target value of the tracking and holding stage, based on the PID gain parameters kp, ki, kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm of the tracking and holding stage are established, and the control parameters kp3, ki3, kd3 of the position loop and the speed loop in the tracking and holding stage are calculated respectively;

[0036] 4) According to the control parameters of different stages obtained in step 3, the turntable performs high-precision tracking control in stages.

[0037] Furthermore, in step 3, the specific steps of confirming the control parameters in stages are:

[0038] When the azimuth error dA satisfies dA≥DA1 or the elevation error dE satisfies dE≥DE1, the turntable is in the tracking and capturing stage, and the P control mode is adopted;

[0039] When the azimuth error dA satisfies DA2≤dA≤DA1 or the elevation error dE satisfies DE2≤dE≤DE1, the turntable is in the middle tracking stage and adopts PID or PI control mode;

[0040] When the azimuth error dA satisfies dA ≤ DA2 or the elevation error dE satisfies dE ≤ DE2, the turntable is in the tracking and holding stage, and the PD or P control mode is adopted;

[0041] Where: DA1 is the maximum value of the azimuth error dA when the measurement value of the turntable azimuth angle ends the rising stage; DA2 is the minimum value of the azimuth error dA when the ratio of the difference between the measurement value and the target value of the turntable azimuth angle to the target value is less than 5%;

[0042] DE1 is the maximum value of the elevation error dE when the measurement value of the turntable elevation angle ends the rising stage; DE2 is the minimum value of the elevation error dE when the ratio of the difference between the measurement value and the target value of the turntable elevation angle to the target value is less than 5%.

[0043] Further, in the step a1, when the azimuth angle and the elevation angle remain unchanged and the working temperature of the turntable is between 10°C and 30°C, the temperature measures the winding torque of the turntable at intervals of 0.1°C; when the working temperature of the turntable is outside the range of 10°C to 30°C, the temperature measures the winding torque of the turntable at intervals of 0.5°C, and obtains the change curve of the winding torque due to temperature change at the same azimuth angle and elevation angle of the turntable.

[0044] Further, in the step a2, when the azimuth angle remains unchanged and the elevation angle changes by 5° each time, when the working temperature of the turntable is between 10°C and 30°C, the temperature measures the winding torque of the turntable at intervals of 0.1°C; when the working temperature of the turntable is outside the range of 10°C to 30°C, the temperature measures the winding torque of the turntable at intervals of 0.5°C, and obtains the change curve of the winding torque due to temperature change at the same azimuth angle and different elevation angles of the turntable.

[0045] Further, in the step a3, when the elevation angle remains unchanged and the azimuth angle changes by 5° each time, when the working temperature of the turntable is between 10°C and 30°C, the temperature measures the winding torque of the turntable at intervals of 0.1°C; when the working temperature of the turntable is outside the range of 10°C to 30°C, the temperature measures the winding torque of the turntable at intervals of 0.5°C, and obtains the change curve of the winding torque due to temperature change at different azimuth angles and the same elevation angle of the turntable.

[0046] Further, in the step b1, when both the azimuth angle and the elevation angle are at the limit positions, when the working temperature of the turntable is between 10°C and 30°C, the temperature measures the friction torque of the turntable at intervals of 0.1°C; when the working temperature of the turntable is outside the range of 10°C to 30°C, the temperature measures the winding torque of the turntable at intervals of 0.5°C, and obtains the change curve of the friction torque due to temperature change at the azimuth angle and elevation angle at the limit positions of the turntable; the limit position is the position of the maximum angle of rotation of the turntable.

[0047] Furthermore, in step b2, when the azimuth angle and the pitch angle are both in the middle position and the operating temperature of the turntable is between 10°C and 30°C, the friction torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the friction torque of the turntable is measured at intervals of 0.5°C, and a friction torque change curve of the turntable due to temperature change at the azimuth and pitch angles in the middle position is obtained; the middle position is the position where the turntable is at zero.

[0048] Furthermore, in step c1, at the same azimuth angle, the moment of inertia of the turntable is measured every 5° change in the pitch angle to obtain a curve of the moment of inertia change of the turntable due to the change in the pitch angle.

[0049] Furthermore, in step c2, at the same pitch angle, the rotational inertia of the turntable is measured every 5° change in the azimuth angle to obtain a rotational inertia change curve of the turntable due to the change in the azimuth angle.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] 1. The present invention provides a two-dimensional turntable capable of adaptive high-precision tracking. The state information of the two-dimensional turntable is detected by a state observation unit, and the data is transmitted to a parameter identification unit. The parameter identification unit calculates the winding torque, friction torque and moment of inertia. The position adaptive controller and the speed adaptive controller respectively calculate the position loop PID gain parameters and the speed loop PID gain parameters based on the parameter identification unit. The position control algorithm unit and the speed control algorithm unit establish and output the control parameters of the corresponding stage according to the azimuth error or the pitch angle error. The two-dimensional turntable can achieve high-precision tracking in stages through the position control algorithm and the speed control algorithm, thereby improving the control accuracy of the two-dimensional turntable.

[0052] 2. The present invention provides a control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking. By establishing a parameter identification model, when the two-dimensional turntable is affected by factors such as temperature, azimuth, and pitch angle, parameter identification is performed on the changes in winding torque, friction torque, and moment of inertia. Based on the parameter identification model, the control parameters of the speed loop and the position loop are automatically changed, solving the problem of poor adaptability of a single parameter. To a certain extent, the two-dimensional turntable avoids the uncertainty caused by winding torque, friction torque, and moment of inertia, solves the problem of unsatisfactory performance of a set of control parameters in certain areas, and realizes high-precision tracking within the entire motion envelope of the turntable, thereby increasing the adaptability range of the two-dimensional turntable to speed.

[0053] 3. The present invention adopts a staged precise tracking mode, which is divided into a tracking capture stage, a tracking intermediate stage and a tracking holding stage. The control parameters are different in the three stages. The control parameters of each stage are confirmed according to the performance to be completed and the winding torque, friction torque and moment of inertia, which solves the problem of the singleness of the control parameters and improves the adaptability and robustness of the control system.

[0054] 4. The present invention can be implemented for different two-dimensional turntables only by changing the software, which is economical and practical, can greatly reduce the workload of debugging personnel, save debugging time, and improve debugging efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 A connection diagram of an embodiment of a two-dimensional turntable capable of realizing adaptive high-precision tracking according to the present invention;

[0056] Figure 2 It is a flow chart of an embodiment of a control method of a two-dimensional turntable capable of realizing adaptive high-precision tracking according to the present invention;

[0057] Figure 3 A schematic diagram of staged control in an embodiment of a control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to the present invention;

[0058] Figure 4 It is a schematic diagram of segmented parameters D1 and D2 functions in an embodiment of a control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to the present invention;

[0059] Figure 5 It is a schematic diagram of the PID gain function in the tracking and capturing stage of an embodiment of a control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to the present invention;

[0060] Figure 6 A schematic diagram of a PID gain function in the tracking intermediate stage in an embodiment of a control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to the present invention;

[0061] Figure 7 It is a schematic diagram of the PID gain function in the tracking and holding stage in an embodiment of the control method of a two-dimensional turntable capable of realizing adaptive high-precision tracking of the present invention. DETAILED DESCRIPTION

[0062] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0063] The present invention proposes a two-dimensional turntable capable of realizing adaptive high-precision tracking, such as Figure 1As shown, it includes a turntable, a turntable motor connected to the input end of the turntable and controlled by current, and an angle measuring unit connected to the angle output end of the turntable. The angle measuring unit is used to measure the azimuth and pitch angle of the turntable; the angle measuring unit is used to measure the azimuth and pitch angle of the turntable; the speed loop located in the inner ring, the position loop located in the outer ring, and the disturbance loop located outside the position loop connected to the disturbance output end of the turntable. The two-dimensional turntable capable of realizing adaptive high-precision tracking also includes a control parameter test system. The state observation unit in the control parameter test system is connected to the state output end of the turntable. The angle measuring unit transmits the measured azimuth and pitch angle to the state observation unit. The state observation unit outputs the temperature of the turntable, as well as the azimuth and pitch angle data, and sends them to the parameter identification unit. The parameter identification unit calculates the winding torque, friction torque and rotational inertia according to the temperature, azimuth and pitch angle data output by the state observation unit; the output end of the parameter identification unit is respectively connected to the input end of the position adaptive controller and the speed adaptive controller.

[0064] The position adaptive controller calculates the corresponding position loop PID gain parameters according to the winding torque, friction torque and moment of inertia output by the parameter identification unit at different temperatures, azimuths and pitch angles of the turntable, and sends them to the position control algorithm unit; the speed adaptive controller calculates the corresponding speed loop PID gain parameters according to the winding torque, friction torque and moment of inertia output by the parameter identification unit at different temperatures, azimuths and pitch angles of the turntable, and sends them to the speed control algorithm unit. The azimuth external guidance target angle input from the turntable is corrected by the disturbance correction algorithm, and the corrected target value is subtracted from the azimuth measurement value obtained by the angle measurement unit to obtain the azimuth error dA of the turntable; the pitch external guidance target angle input from the turntable is corrected by the disturbance correction algorithm, and the corrected target value is subtracted from the pitch measurement value obtained by the angle measurement unit to obtain the pitch error dE of the turntable. The azimuth error dA or the pitch angle error dE is input into the position control algorithm unit. The position control algorithm unit establishes the position control algorithm of the corresponding stage under the corresponding temperature, azimuth angle, and pitch angle according to the error and the position loop PID gain parameter, and outputs the azimuth rate error dωA or the pitch angle rate error dωE. The azimuth rate error dωA or the pitch angle rate error dωE is input into the speed control algorithm unit. The speed control algorithm unit establishes the speed control algorithm of the corresponding stage under the corresponding temperature, azimuth angle, and pitch angle according to the error and the speed loop PID gain parameter. By inputting the temperature, azimuth angle, and pitch angle into the two-dimensional turntable, the control parameters of the two-dimensional turntable can be automatically adjusted according to the speed control algorithm and the position control algorithm, thereby improving the control accuracy of the two-dimensional turntable.

[0065] The present invention also provides a control method for the two-dimensional turntable capable of realizing adaptive high-precision tracking, such as Figure 2 As shown, the following steps are included:

[0066] 1) A parameter identification model is established for the changes of winding torque, friction torque and moment of inertia during the rotation of the turntable, as well as the changes of temperature and other factors. Including winding torque parameter identification model, friction torque parameter identification model and moment of inertia parameter identification model, the parameter identification unit of the turntable calculates the winding torque, friction torque and moment of inertia according to the established parameter identification model.

[0067] The winding torque is affected by the rotation angle of the two-dimensional turntable, namely the azimuth and pitch angle, and is also affected by temperature. Therefore, the azimuth, pitch angle, and temperature variables are controlled respectively to measure the change in the winding torque; the steps for establishing the winding torque parameter identification model are as follows:

[0068] a1) The turntable measures the winding torque at different temperatures at the same azimuth and elevation angles to generate a temperature-winding torque variation curve;

[0069] When the azimuth and elevation angles are kept unchanged and the operating temperature of the turntable is between 10°C and 30°C, the winding torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the winding torque of the turntable is measured at intervals of 0.5°C, and the winding torque change curve of the turntable due to temperature change at the same azimuth and elevation angles is obtained.

[0070] a2) The turntable measures the winding torque at different temperatures at the same azimuth and different pitch angles, and generates a pitch angle, temperature-winding torque variation curve;

[0071] Keeping the azimuth angle unchanged, the pitch angle changes by 5°, and when the operating temperature of the turntable is between 10°C and 30°C, the winding torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the winding torque of the turntable is measured at intervals of 0.5°C, and the winding torque change curve of the turntable due to temperature change at the same azimuth angle and different pitch angles is obtained.

[0072] a3) The turntable measures the winding torque at different temperatures at different azimuth angles and the same pitch angle, and generates the azimuth angle, temperature-winding torque variation curve;

[0073] Keeping the pitch angle unchanged, the azimuth angle changes by 5°, and when the operating temperature of the turntable is between 10°C and 30°C, the winding torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the winding torque of the turntable is measured at intervals of 0.5°C, and the winding torque change curve of the turntable due to temperature change at different azimuth angles and the same pitch angle is obtained.

[0074] a4) Based on the change curves generated in steps a1 to a3, a three-dimensional table with the turntable azimuth angle, pitch angle and temperature changes is generated to obtain a winding torque parameter identification model; when the azimuth angle, pitch angle and winding temperature of the two-dimensional turntable are input, the current winding torque can be identified.

[0075] Friction is greatly affected by temperature. Within the working angle range of the turntable, the azimuth and pitch angles at the extreme position and the middle position are selected to measure the change of friction torque with temperature, so as to improve the accuracy of the friction torque parameter identification model. The extreme position is the position of the maximum angle of the turntable, and the middle position is the position of the turntable at zero position. The steps for establishing the friction torque parameter identification model are as follows:

[0076] b1) When the azimuth and elevation angles of the turntable are at the extreme positions, measure the friction torque at different temperatures and generate the temperature-friction torque variation curve at the extreme position;

[0077] When the azimuth and pitch angles are both at extreme positions and the operating temperature of the turntable is between 10℃ and 30℃, the friction torque of the turntable is measured at intervals of 0.1℃; when the operating temperature of the turntable is outside the range of 10℃ to 30℃, the winding torque of the turntable is measured at intervals of 0.5℃, and the friction torque change curve of the turntable due to temperature change at the azimuth and pitch angles at the extreme positions is obtained.

[0078] b2) When the azimuth and elevation angles of the two-dimensional turntable are at the middle position, measure the friction torque at different temperatures;

[0079] When the azimuth and pitch angles are both at the middle position and the operating temperature of the turntable is between 10°C and 30°C, the friction torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the friction torque of the turntable is measured at intervals of 0.5°C, and the friction torque change curve of the turntable due to temperature change is obtained at the azimuth and pitch angles at the middle position.

[0080] b3) According to step b1 and step b2, a friction torque parameter identification model is obtained. When the azimuth angle, pitch angle and temperature of the two-dimensional turntable are input, the current friction torque can be identified.

[0081] The moment of inertia is related to the azimuth and pitch angles of the two-dimensional turntable. The azimuth and pitch angles are controlled separately to measure the change in the moment of inertia. The steps for establishing the moment of inertia parameter identification model are as follows:

[0082] c1) The turntable measures the moment of inertia at different pitch angles at the same azimuth angle, and generates a pitch angle-moment of inertia variation curve;

[0083] At the same azimuth, the pitch angle changes by 5° at intervals, and the moment of inertia of the turntable is measured to obtain a curve of the change of the moment of inertia of the turntable due to the change of the pitch angle.

[0084] c2) The turntable measures the moment of inertia at different azimuth angles at the same pitch angle, and generates the azimuth-moment of inertia change curve;

[0085] At the same pitch angle, the azimuth angle changes by 5° at intervals, and the rotational inertia change curve of the turntable due to the change of the azimuth angle is obtained.

[0086] c3) According to step c1 and step c2, a rotational inertia parameter identification model is obtained, and when the azimuth angle and pitch angle of the two-dimensional turntable are input, the current rotational inertia can be identified.

[0087] 2) According to the parameter identification model obtained in step 1, the changes of the temperature T, azimuth angle A, and pitch angle E of the input turntable are used, and the position adaptive controller and the speed adaptive controller calculate the PID gain parameters kp, ki, and kd of the position loop and the speed loop respectively;

[0088] 3) According to the azimuth error dA or the pitch angle error dE and the PID gain parameters obtained in step 2, the control parameters are confirmed in stages, and the position loop and the speed loop establish the position control algorithm and the speed control algorithm of the corresponding tracking stage. The tracking stage includes the tracking capture stage, the tracking intermediate stage and the tracking holding stage. If the speed loop and the position loop are used separately, the position loop makes staged judgments based on the angle error, and the speed loop makes staged judgments based on the angular velocity error. In this embodiment, the speed loop is used in connection with the position loop, so the staged judgments of the position loop and the speed loop can be realized by using the azimuth error dA or the pitch angle error dE. Figure 3 , Figure 4 As shown,

[0089] When the azimuth error dA satisfies dA≥DA1 or the elevation error dE satisfies dE≥DE1, the turntable is in the tracking and capturing stage, and the P control mode is adopted;

[0090] When the azimuth error dA satisfies DA2≤dA≤DA1 or the elevation error dE satisfies DE2≤dE≤DE1, the turntable is in the middle tracking stage and adopts PID or PI control mode;

[0091] When the azimuth error dA satisfies dA≤DA2 or the elevation error dE satisfies dE≤DE2, the turntable is in the tracking and holding stage, and the PD or P control mode is adopted;

[0092] Wherein: DA1 is the maximum value of the azimuth error dA at the end of the rising stage of the measured value of the turntable azimuth; DA2 is the minimum value of the azimuth error dA when the difference between the measured value of the turntable azimuth and the target value and the ratio of the target value are both less than 5%;

[0093] DE1 is the maximum value of the pitch angle error dE at the end of the rising phase of the measured value of the turntable pitch angle; DE2 is the minimum value of the pitch angle error dE when the ratio of the difference between the measured value of the turntable pitch angle and the target value and the target value are both less than 5%.

[0094] 3.1) Tracking and capturing stage: According to the target value of the tracking and capturing stage, based on the PID gain parameters kp, ki, and kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm of the tracking and capturing stage are established, as follows: Figure 5 As shown, according to f1(T / A / E), the control parameters kp1, ki1, and kd1 of the position loop and the speed loop in the tracking and capturing phase are calculated respectively.

[0095] 3.2) In the intermediate tracking stage, according to the target value in the intermediate tracking stage, based on the PID gain parameters kp, ki, and kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm in the intermediate tracking stage are established, such as Figure 6 As shown, based on f2(T / A / E), the control parameters kp2, ki2, and kd2 of the position loop and the speed loop in the intermediate tracking stage are calculated respectively.

[0096] 3.3) Tracking and holding stage: According to the target value of the tracking and holding stage, based on the PID gain parameters kp, ki, and kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm of the tracking and holding stage are established, such as Figure 7 As shown, based on f3(T / A / E), the control parameters kp3, ki3, and kd3 of the position loop and the speed loop in the tracking and holding stage are calculated respectively.

[0097] 4) According to the control parameters of different stages obtained in step 3, the turntable performs high-precision tracking control in stages.

[0098] In the process of the two-dimensional turntable movement, the parameter identification model in the parameter identification unit can calculate the winding torque, friction torque and moment of inertia according to the detection data of the state observation unit; the position adaptive controller and the speed adaptive controller calculate the corresponding PID gain parameters in stages according to step 2. The speed control algorithm unit and the position control algorithm unit adjust the tracking of the two-dimensional turntable according to the control parameters of different stages to ensure that the two-dimensional turntable always works in the optimal state, reduce the accuracy reduction and untrackability caused by the change of resistance torque such as winding torque, friction torque and the change of moment of inertia, and improve the control accuracy and adaptability of the two-dimensional turntable while reducing the influence of disturbance torque fluctuation.

Claims

1. A two-dimensional turntable capable of realizing adaptive high-precision tracking, comprising a turntable, a turntable motor connected to an input end of the turntable and controlled by current, an angle measuring unit connected to an angle output end of the turntable, a speed loop located in an inner ring connected to the angle measuring unit, a position loop located in an outer ring, and a disturbance loop located outside the position loop connected to a disturbance output end of the turntable; the speed loop comprises a speed control algorithm unit; the position loop comprises a position control algorithm unit; the angle measuring unit is used to measure the azimuth angle and the pitch angle of the turntable; Features: It also includes a control parameter testing system, which includes a state observation unit, a parameter identification unit, a position adaptive controller, and a speed adaptive controller; The state observation unit is connected to the state output terminal of the turntable, the angle measuring unit transmits the measured azimuth and pitch angle to the state observation unit, and the state observation unit outputs the temperature of the turntable, as well as the azimuth and pitch angle data, and sends them to the parameter identification unit; The parameter identification unit calculates the winding torque, friction torque and moment of inertia according to the temperature, azimuth angle and pitch angle output by the state observation unit; the output end of the parameter identification unit is connected to the input end of the position adaptive controller and the speed adaptive controller respectively; The position adaptive controller calculates the corresponding position loop PID gain parameters according to the winding torque, friction torque and rotational inertia output by the parameter identification unit at different temperatures, azimuth angles and pitch angles of the turntable, and sends them to the position control algorithm unit; The speed adaptive controller calculates the corresponding speed loop PID gain parameters according to the winding torque, friction torque and rotational inertia output by the parameter identification unit at different temperatures, azimuth angles and pitch angles of the turntable, and sends them to the speed control algorithm unit; The position control algorithm unit establishes a position control algorithm for the corresponding stage under the corresponding temperature, azimuth angle, and pitch angle according to the azimuth angle error dA or the pitch angle error dE and the position loop PID gain parameter, and outputs the azimuth angle rate error dωA or the pitch angle rate error dωE; The speed control algorithm unit establishes a speed control algorithm for the corresponding stage under the corresponding temperature, azimuth angle and pitch angle according to the azimuth rate error dωA or the pitch rate error dωE output by the position control algorithm and the speed loop PID gain parameter; The azimuth error dA is the difference between the target value of the azimuth external guidance target angle input from the turntable and corrected by the disturbance correction algorithm and the azimuth measurement value obtained by the angle measurement unit; The pitch angle error dE is the difference between the target value of the pitch angle external guidance target angle input from the turntable after being corrected by the disturbance correction algorithm and the pitch angle measurement value obtained by the angle measurement unit.

2. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking as claimed in claim 1, Features: The following steps are involved: 1) Establishing a parameter identification model; the parameter identification model includes a winding torque parameter identification model, a friction torque parameter identification model and a moment of inertia parameter identification model, and the parameter identification unit calculates the winding torque, friction torque and moment of inertia according to the parameter identification model, wherein: The steps for establishing the winding torque parameter identification model are as follows: a1) The turntable measures the winding torque at different temperatures at the same azimuth and elevation angles to generate a temperature-winding torque variation curve; a2) The turntable measures the winding torque at different temperatures at the same azimuth and different pitch angles, and generates a pitch angle, temperature-winding torque variation curve; a3) The turntable measures the winding torque at different temperatures at different azimuth angles and the same pitch angle, and generates the azimuth angle, temperature-winding torque variation curve; a4) obtaining a winding torque parameter identification model according to the variation curves generated in steps a1 to a3; The steps to establish the friction torque parameter identification model are as follows: b1) When the azimuth and elevation angles of the turntable are at the extreme positions, measure the friction torque at different temperatures and generate the temperature-friction torque variation curve at the extreme position; b2) When the azimuth angle and the pitch angle of the turntable are both at the middle position, the friction torque at different temperatures is measured to generate a temperature-friction torque variation curve at the middle position; b3) obtaining a friction torque parameter identification model according to the variation curves generated in step b1 and step b2; The steps to establish the moment of inertia parameter identification model are as follows: c1) The turntable measures the moment of inertia at different pitch angles at the same azimuth angle, and generates a pitch angle-moment of inertia variation curve; c2) The turntable measures the moment of inertia at different azimuth angles at the same pitch angle, and generates the azimuth-moment of inertia change curve; c3) obtaining a moment of inertia parameter identification model according to the change curves generated in step c1 and step c2; 2) Based on the parameter identification model obtained in step 1, the position adaptive controller and the speed adaptive controller calculate the PID gain parameters kp, ki, and kd of the position loop and the speed loop respectively according to the changes in the temperature T, azimuth angle A, and pitch angle E of the turntable; 3) According to the azimuth error dA or the pitch angle error dE and the PID gain parameters obtained in step 2, the control parameters are confirmed in stages, and the position loop and the speed loop establish the position control algorithm and the speed control algorithm of the corresponding tracking stage. The tracking stage includes the tracking capture stage, the tracking intermediate stage and the tracking holding stage: 3.1) In the tracking and capturing stage, according to the target value of the tracking and capturing stage, based on the PID gain parameters kp, ki, and kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm of the tracking and capturing stage are established, and the control parameters kp1, ki1, and kd1 of the position loop and the speed loop in the tracking and capturing stage are calculated respectively; 3.2) In the intermediate tracking stage, according to the target value in the intermediate tracking stage, based on the PID gain parameters kp, ki, kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm in the intermediate tracking stage are established, and the control parameters kp2, ki2, kd2 of the position loop and the speed loop in the intermediate tracking stage are calculated respectively; 3.3) In the tracking and holding stage, according to the target value of the tracking and holding stage, based on the PID gain parameters kp, ki, kd output by the position adaptive controller and the speed adaptive controller, the position control algorithm and the speed control algorithm of the tracking and holding stage are established, and the control parameters kp3, ki3, kd3 of the position loop and the speed loop in the tracking and holding stage are calculated respectively; 4) According to the control parameters of different stages obtained in step 3, the turntable performs high-precision tracking control in stages.

3. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 2, Features: In step 3, the specific steps for confirming the control parameters in stages are: When the azimuth error dA satisfies dA≥DA1 or the elevation error dE satisfies dE≥DE1, the turntable is in the tracking and capturing stage, and the P control mode is adopted; When the azimuth error dA satisfies DA2≤dA≤DA1 or the elevation error dE satisfies DE2≤dE≤DE1, the turntable is in the middle tracking stage and adopts PID or PI control mode; When the azimuth error dA satisfies dA≤DA2 or the elevation error dE satisfies dE≤DE2, the turntable is in the tracking and holding stage, and the PD or P control mode is adopted; Wherein: DA1 is the maximum value of the azimuth error dA at the end of the rising stage of the measured value of the turntable azimuth; DA2 is the minimum value of the azimuth error dA when the difference between the measured value of the turntable azimuth and the target value and the ratio of the target value are both less than 5%; DE1 is the maximum value of the pitch angle error dE at the end of the rising phase of the measured value of the turntable pitch angle; DE2 is the minimum value of the pitch angle error dE when the ratio of the difference between the measured value of the turntable pitch angle and the target value and the target value are both less than 5%.

4. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 2 or 3, Features: In the step a1, the azimuth angle and the pitch angle are kept unchanged. When the operating temperature of the turntable is between 10°C and 30°C, the winding torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the winding torque of the turntable is measured at intervals of 0.5°C, and a winding torque change curve of the turntable due to temperature change at the same azimuth angle and pitch angle is obtained.

5. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 4, Features: In the step a2, the azimuth angle is kept unchanged, and the pitch angle is changed by 5°. When the operating temperature of the turntable is between 10°C and 30°C, the winding torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the winding torque of the turntable is measured at intervals of 0.5°C, to obtain the winding torque change curve of the turntable due to temperature change at the same azimuth angle and different pitch angles.

6. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 5, Features: In the step a3, the pitch angle is kept unchanged, and the azimuth angle is changed by 5°. When the operating temperature of the turntable is between 10°C and 30°C, the winding torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the winding torque of the turntable is measured at intervals of 0.5°C, to obtain the winding torque change curve of the turntable due to temperature change at different azimuth angles and the same pitch angle.

7. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 6, Features: In the step b1, when the azimuth angle and the pitch angle are both at the extreme positions and the operating temperature of the turntable is between 10°C and 30°C, the friction torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the winding torque of the turntable is measured at intervals of 0.5°C to obtain a friction torque change curve due to temperature changes at the azimuth and pitch angles of the turntable at the extreme positions; the extreme position is the position of the maximum rotation angle of the turntable.

8. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 7, Features: In the step b2, when the azimuth angle and the pitch angle are both at the middle position and the operating temperature of the turntable is between 10°C and 30°C, the friction torque of the turntable is measured at intervals of 0.1°C; when the operating temperature of the turntable is outside the range of 10°C to 30°C, the friction torque of the turntable is measured at intervals of 0.5°C, and a friction torque change curve of the turntable due to temperature change at the azimuth and pitch angles at the middle position is obtained; the middle position is the position where the turntable is at zero.

9. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 8, Features: In the step c1, at the same azimuth angle, the moment of inertia of the turntable is measured every 5° change in the pitch angle, and a curve of the moment of inertia change of the turntable due to the change in the pitch angle is obtained.

10. A control method for a two-dimensional turntable capable of realizing adaptive high-precision tracking according to claim 9, Features: In step c2, at the same pitch angle, the rotational inertia of the turntable is measured every 5° change in the azimuth angle, and a rotational inertia change curve of the turntable due to the change in the azimuth angle is obtained.

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