Performance testing device and method for fine tracking system based on coarse tracking error driving

Abstract

The invention discloses a performance testing device and method for a fine tracking system based on coarse tracking error driving, and relates to the field of composite axis tracking control. Comprising a light source, an off-axis reflection type collimator, a target simulation fast reflecting mirror, a fine detector, a fine tracking fast reflecting mirror, a fine tracking controller, a coarse tracking platform dynamics simulation computer, a coarse tracking platform management unit, a collimator holder mechanism, a primary mirror and a secondary mirror. The method comprises the following steps: driving a target simulation fast reflecting mirror to move by using an error of a coarse tracking system, coupling a target to a fine tracking system through an off-axis reflective collimator, extracting by a fine detector to obtain a miss distance, and finishing image closed-loop control by using the miss distance fine tracking fast reflecting mirror. And meanwhile, the fine tracking system outputs the unloading amount to the coarse tracking simulation system to complete unloading of the coarse and fine two-stage system. According to the method, key function and performance verification of the fine tracking system can be completed in an environment without a real coarse tracking platform, the test cost is effectively saved, and practical engineering application is facilitated.

Description

Technical Field

[0001] The invention relates to the field of composite axis tracking control, and in particular to a performance testing device and method for a fine tracking system driven by a coarse tracking error. Background Art

[0002] The composite axis tracking system is a high-precision tracking system composed of two-level subsystems, with a wide dynamic range and fast response speed. The tracking accuracy can reach the micro-radian level. It is widely used in optical communications, laser ranging, beam stabilization and other fields. Coarse tracking is usually completed by a two-dimensional turntable with low accuracy but large motion stroke to achieve coarse capture of the tracking target, and fine tracking is completed by a tilt mirror with a small stroke but high bandwidth to achieve high-precision tracking of the target.

[0003] At present, for the test and verification of the key unloading function and tracking accuracy of the composite axis tracking system, the two-stage tracking system needs to be assembled, and the performance test of the composite axis tracking system cannot be completed without a real coarse tracking platform. However, it is often difficult to realize the combination of the two-stage tracking system due to the limitations of site, time and cost. Summary of the invention

[0004] In order to overcome the shortcomings of the existing composite axis tracking system performance test method, the present invention provides a test device and test method that can complete the composite axis performance verification without a real coarse tracking platform, and can complete the verification of the tracking accuracy performance and unloading function of the fine tracking system in an environment without a real coarse tracking platform. The test process is simple and convenient, and does not require a large amount of manpower and material resources to carry out the assembly and debugging of the coarse and fine levels, shortening the test time of the key unloading function and tracking accuracy performance of the coarse and fine composite axis tracking system, effectively saving the test cost, which is very beneficial to practical engineering applications.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme:

[0006] A performance test device for a fine tracking system driven by a coarse tracking error comprises a coarse tracking simulation system, a fine tracking system, a light source, an off-axis reflective collimator, and a collimator pan-tilt mechanism; the coarse tracking simulation system comprises a coarse tracking platform dynamics simulation computer, a coarse tracking platform management unit, and a target simulation fast-reflection mirror; the fine tracking system comprises a fine detector, a fine tracking fast-reflection mirror, a fine tracking controller, a primary mirror, and a secondary mirror;

[0007] The target generated by the light source passes through the target simulation fast reflex mirror to the off-axis reflective collimator to form a parallel light beam. The parallel light beam passes through the primary mirror and the secondary mirror in the fine tracking system and reaches the fine tracking fast reflex mirror. It is reflected by the fine tracking fast reflex mirror and enters the fine detector. The fine detector extracts the image miss amount information. The fine tracking controller is connected to the fine detector through a serial port to receive the image miss amount information, which is used for the closed-loop control of the fine tracking fast reflex mirror. The calculated control amount is sent to the driver of the fine tracking fast reflex mirror through the fine tracking controller to drive the fine tracking fast reflex mirror to deflect, so as to realize the image closed-loop control. The fine tracking controller sends the unloading amount to the coarse tracking platform management unit through the serial port. The coarse tracking platform dynamics simulation computer communicates with the coarse tracking platform management unit. The coarse tracking platform dynamics simulation computer is used to simulate the on-orbit working conditions. The collimator pan / tilt mechanism controls the movement of the off-axis reflective collimator to test the unloading amount polarity output by the fine tracking system.

[0008] The present invention also provides a performance testing method of a performance testing device of a fine tracking system driven by a coarse tracking error, comprising the following steps:

[0009] Step 1: forming a performance test device of a fine tracking system driven by a coarse tracking error;

[0010] Step 2: Conduct polarity test of the unloading amount sent by the fine tracking system to the coarse tracking simulation system;

[0011] Step 3: Conduct polarity and dimension test of voltage value of target simulated fast mirror in coarse tracking simulation system;

[0012] Step 4: Complete the dimensional test of the unloading amount output from the fine tracking system to the coarse tracking simulation system;

[0013] Step 5. Conduct experiments using the performance test device of the fine tracking system driven by coarse tracking errors. The coarse tracking platform dynamics simulation computer sends coarse tracking errors to guide the target into the field of view of the fine tracking system. The fine tracking fast reflex mirror uses the miss-target amount to complete the image closed loop and outputs the unloading amount to the coarse tracking simulation system in real time. The coarse tracking platform dynamics simulation computer performs bias control based on the unloading amount to collaboratively reduce errors. Considering on-orbit usage, complete the verification of the fine tracking system's image processing, closed loop, unloading function, and tracking accuracy performance.

[0014] Beneficial effects:

[0015] The present invention proposes a test and verification method for the key unloading function and tracking accuracy performance of a composite axis tracking system that does not require a coarse tracking platform. The method utilizes a large-stroke target simulation fast-reflection mirror to replace the coarse tracking platform, and combines a coarse tracking platform dynamics simulation computer to simulate complex on-orbit conditions. The method can verify the image closed-loop, unloading function and tracking accuracy performance indicators of the coarse-fine composite axis system in an environment without a coarse tracking platform. The test process is simple and convenient, and does not require a large amount of manpower and material resources to assemble and debug the coarse-fine two-level system. The test time of the key unloading function and tracking accuracy performance of the coarse-fine composite axis tracking system is shortened, the test cost is effectively saved, and it is very beneficial to practical engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a performance testing device of a fine tracking system driven by coarse tracking error according to the present invention.

[0017] Figure 2 This is a comparison chart of the control amount of the fine tracking fast reflection mirror before and after unloading control of the coarse tracking simulation system.

[0018] Among them, the accompanying drawings are marked as follows: A is a coarse tracking simulation system; B is a fine tracking system; 1 is a coarse tracking platform dynamics simulation computer; 2 is a coarse tracking platform management unit; 3 is a light source; 4 is a target simulation fast reflex mirror; 5 is an off-axis reflective collimator; 6 is a collimator pan-tilt mechanism; 7 is a primary mirror; 8 is a secondary mirror; 9 is a fine tracking fast reflex mirror; 10 is a fine detector; and 11 is a fine tracking controller. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other. The present invention is described below in conjunction with the accompanying drawings and specific embodiments, and those skilled in the art can understand the effects and advantages of the present invention based on the contents disclosed in this specification.

[0020] like Figure 1As shown, the present invention provides a performance test device for a fine tracking system driven by a coarse tracking error, which mainly includes a coarse tracking simulation system A and a fine tracking system B. The coarse tracking simulation system A includes a coarse tracking platform dynamics simulation computer 1, a coarse tracking platform management unit 2 and a target simulation fast reflex mirror 4. The fine tracking system B includes a fine detector 10, a fine tracking fast reflex mirror 9, a fine tracking controller 11, a primary mirror 7 and a secondary mirror 8. In addition, the performance test device for a fine tracking system driven by a coarse tracking error also includes a light source 3, an off-axis reflective collimator 5 and a collimator pan / tilt mechanism 6.

[0021] Among them, the target generated by the light source 3 passes through the target simulation fast reflection mirror 4 to the off-axis reflective collimator 5 to obtain a parallel light beam, and the parallel light beam passes through the primary mirror 7 and the secondary mirror 8 of the optical-mechanical combination in the fine tracking system B and reaches the fine tracking fast reflection mirror 9, and is reflected by the fine tracking fast reflection mirror 9 into the fine detector 10, and the fine detector 10 extracts the image off-target amount information. The fine tracking controller 11 is connected to the fine detector 10 through a serial port, receives the image off-target amount, and is used for the closed-loop control of the fine tracking fast reflection mirror 9. The calculated control amount is sent to the fine tracking fast reflection mirror 9 driver through the fine tracking controller 11 to drive the fine tracking fast reflection mirror 9 to deflect, so as to realize the image closed-loop control. The fine tracking controller 11 sends the unloading amount to the coarse tracking platform management unit 2 through the serial port, and the coarse tracking platform dynamics simulation computer 1 communicates with the coarse tracking platform management unit 2, and the coarse tracking platform dynamics simulation computer 1 is used to simulate the on-orbit working conditions. The collimator pan-tilt mechanism 6 is rigidly connected to the off-axis reflective collimator 5 , and can control the movement of the off-axis reflective collimator 5 to test the polarity of the unloading amount output by the fine tracking system B.

[0022] Preferably, the coarse tracking error is used to drive the target to simulate the fast mirror 4, which can simulate the movement of the real coarse tracking platform, so as to complete the verification of fine tracking system image processing, closed loop, unloading function and tracking accuracy performance without the real coarse tracking platform.

[0023] Preferably, the rough tracking platform dynamics simulation computer 1 is used to simulate different complex working conditions on orbit.

[0024] Preferably, the target simulated fast reflex mirror 4 used is a fast reflex mirror driven by a voice coil motor, which has the characteristic of a large deflection angle, and can therefore be used to simulate a coarse tracking platform with a wide dynamic range.

[0025] Preferably, the off-axis reflective collimator is moved in the horizontal and vertical directions by using the collimator pan / tilt mechanism 6, so as to test the polarity of the unloading amount output by the fine tracking system B and verify whether there is image rotation between the imaging plane and the measurement coordinate system.

[0026] Preferably, when there is image rotation between the imaging plane and the measurement coordinate system, the unloading amount needs to be derotated before being sent to the coarse tracking simulation system A. Only after derotation can the correct polarity be output. The rotation relationship is as follows:

[0027] ;

[0028] in, is the fixed rotation angle between the imaging plane and the measurement coordinate system, and are the azimuth unloading and pitch unloading before unspinning, respectively; and They are the azimuth unloading and pitch unloading output to the coarse tracking simulation system after derotation.

[0029] The present invention also provides a performance testing method of a performance testing device of a fine tracking system driven by a coarse tracking error, comprising the following steps:

[0030] Step 1: Press Figure 1 Lay out and connect performance test equipment;

[0031] Step 2: Conduct a polarity test on the unloading amount sent by the fine tracking system B to the coarse tracking simulation system A. Control the movement of the off-axis reflective collimator 5 through the collimator pan / tilt mechanism 6, and deflect the optical axis of the collimator in the horizontal and vertical directions in turn, and test the polarity in a single direction to verify whether the imaging is rotated. If there is rotation, calculate the rotation angle and then perform the derotation according to the rotation formula described above. Rotate the off-axis reflective collimator in a predetermined direction to test whether the polarity of the azimuth unloading amount and the pitch unloading amount output by the fine tracking system to the coarse tracking simulation system are consistent with the proposed protocol. Perform polarity calibration to make the polarity of the unloading amount consistent with the protocol.

[0032] Step 3: calibrate the polarity and dimension of the voltage value of the target simulation fast reflection mirror 4 in the coarse tracking simulation system A.

[0033] First, complete the communication test between the rough tracking platform dynamics simulation computer 1 and the rough tracking platform management unit 2, and the rough tracking platform management unit 2 and the target simulation fast reflex mirror 4. Complete the calibration of the voltage polarity and dimension of the target simulation fast reflex mirror 4, so that the target simulation fast reflex mirror 4 can follow the azimuth output by the rough tracking platform dynamics simulation computer 1. and pitch angle , control the target to deflect to the desired pixel position on the image plane of the fine tracking system B. In addition, fine-tune the optical path so that the deflection angle range meets the requirements.

[0034] Step 4: Complete the dimensional test of the unloading amount output by the fine tracking system B to the coarse tracking simulation system A.

[0035] The fine tracking fast reflection mirror 9 is in the open loop and closed loop states, and the rough tracking platform dynamics simulation computer 1 sends the azimuth and pitch angle The control target simulates the movement of the fast-reflection mirror 4, simulates the deflection of the coarse tracking platform by an angle, and unloads the azimuth output of the fine tracking system. and pitch unloading (i.e. the azimuth unloading and pitch unloading output to the coarse tracking simulation system after derotation) are calibrated so that and .

[0036] Step 5: Utilization Figure 1 The test was carried out using the performance test device.

[0037] First, the rough tracking platform dynamics simulation computer 1 sends the azimuth Simulate a fast-reflection mirror 4 for the target, make the target deviate from the field of view, and then send the azimuth angle Small offset angle Simulate the coarse tracking error and guide the target into the field of view of the fine tracking system. Once the miss distance is valid, the fine tracking fast-reflection mirror 9 automatically completes the image closed loop and outputs the unloading distance to the coarse tracking simulation system A in real time. Azimuth , offset angle .

[0038] If the coarse tracking simulation system A starts the unloading mode, the coarse tracking platform dynamics simulation computer 1 performs bias control according to the unloading amount to collaboratively reduce the tracking error. Figure 2 The change of the control amount of the fine tracking fast mirror before and after the unloading is turned on is shown. Due to the large tracking error at the beginning, the closed-loop control amount of the fine tracking fast mirror reaches the saturation threshold of 32000, which is a pure numerical value, and 16 numbers are equivalent to 0.9 micro-radians. After the coarse tracking simulation system turns on the unloading mode, the control amount is significantly reduced and maintained near 0, indicating that the coarse tracking simulation system successfully unloads the fine tracking system, and the target tracking range and tracking accuracy are increased. At the same time, the coarse tracking platform dynamics simulation computer 1 sends a bias simulation target entering the field of view → the target exits the field of view → the target re-enters the field of view, which can complete the image processing of the fine tracking system and the verification of the closed-loop key functions.

[0039] For multi-aperture (multi-dimensional system with multiple precision tracking fast-reflecting mirrors) and three-level or even multi-level composite optoelectronic tracking systems, the method proposed in the present invention is still applicable and is also within the scope of protection.

[0040] The contents not described in detail in the specification are prior art known to those skilled in the art.

Claims

1. A performance test device for a fine tracking system driven by a coarse tracking error, characterized in that: It includes a coarse tracking simulation system, a fine tracking system, a light source, an off-axis reflective collimator, and a collimator pan / tilt mechanism; the coarse tracking simulation system includes a coarse tracking platform dynamics simulation computer, a coarse tracking platform management unit, and a target simulation fast-reflection mirror; the fine tracking system includes a fine detector, a fine tracking fast-reflection mirror, a fine tracking controller, a primary mirror, and a secondary mirror; The target generated by the light source passes through the target simulation fast reflection mirror and then reaches the off-axis reflective collimator to form a parallel light beam. The parallel light beam passes through the primary mirror and secondary mirror in the precision tracking system and then reaches the precision tracking fast reflection mirror. After being reflected by the precision tracking fast reflection mirror, it enters the precision detector, which extracts the image miss distance information. The fine tracking controller is connected to the fine detector through the serial port to receive the image off-target amount information, which is used for the closed-loop control of the fine tracking fast reflex mirror. The calculated control amount is sent to the driver of the fine tracking fast reflex mirror through the fine tracking controller to drive the fine tracking fast reflex mirror to deflect, thereby realizing the image closed-loop control. The fine tracking controller sends the unloading amount to the coarse tracking platform management unit through the serial port. The coarse tracking platform dynamics simulation computer communicates with the coarse tracking platform management unit. The coarse tracking platform dynamics simulation computer is used to simulate the on-orbit working conditions. The collimator pan-tilt mechanism controls the movement of the off-axis reflective collimator to test the polarity of the unloading amount output by the fine tracking system.

2. A performance test device for a fine tracking system driven by a coarse tracking error as claimed in claim 1, characterized in that: The coarse tracking error is used to drive the target to simulate the fast reflection mirror to simulate the movement of the real coarse tracking platform, so as to complete the image processing, closed loop, unloading function and tracking accuracy performance verification of the fine tracking system without the real coarse tracking platform.

3. The performance test device of a fine tracking system driven by a coarse tracking error according to claim 1, characterized in that: The rough tracking platform dynamics simulation computer is used to simulate different complex working conditions on orbit.

4. The performance test device of a fine tracking system driven by a coarse tracking error according to claim 1, characterized in that: The target simulated fast reflex mirror is a fast reflex mirror driven by a voice coil motor and is used to simulate a coarse tracking platform with a wide dynamic range.

5. The performance test device of a fine tracking system driven by a coarse tracking error according to claim 1, characterized in that: The off-axis reflective collimator is moved in the horizontal and vertical directions using the collimator pan / tilt mechanism to test the polarity of the unloading output by the precision tracking system and verify whether there is image rotation between the imaging plane and the measurement coordinate system.

6. The performance test device of a fine tracking system driven by a coarse tracking error according to claim 5, characterized in that: In the case that there is image rotation between the imaging plane and the measurement coordinate system, the unloading amount is derotated and then sent to the coarse tracking simulation system, and the correct unloading amount is output after derotation; the rotation relationship is as follows: ； in, is the fixed rotation angle between the imaging plane and the measurement coordinate system, and are the azimuth unloading and pitch unloading before unspinning, respectively; and They are the azimuth unloading and pitch unloading output to the coarse tracking simulation system after derotation.

7. The performance testing method of the performance testing device of the fine tracking system driven by coarse tracking error according to claim 1, characterized in that: The following steps are involved: Step 1: forming a performance test device of a fine tracking system driven by a coarse tracking error; Step 2: Conduct polarity test of the unloading amount sent by the fine tracking system to the coarse tracking simulation system; Step 3: Conduct polarity and dimension test of voltage value of target simulated fast mirror in coarse tracking simulation system; Step 4: Complete the dimensional test of the unloading amount output from the fine tracking system to the coarse tracking simulation system; Step 5: Conducting tests using a performance test device for a fine tracking system driven by a coarse tracking error; The coarse tracking platform dynamics simulation computer sends the coarse tracking error to guide the target into the field of view of the fine tracking system. The fine tracking fast reflection mirror uses the miss-target amount to complete the image closed loop and outputs the unloading amount to the coarse tracking simulation system in real time. The coarse tracking platform dynamics simulation computer performs bias control according to the unloading amount to jointly reduce the error. Considering the on-orbit usage, the image processing, closed loop, unloading function and tracking accuracy performance of the fine tracking system are verified.

8. The performance testing method according to claim 7, characterized in that: The second step includes: controlling the movement of the off-axis reflective collimator through the collimator pan / tilt mechanism, deflecting the collimator in the horizontal and vertical directions in sequence, performing a polarity test to verify whether the image is rotated; if there is rotation, calculating the rotation angle and performing derotation according to the following formula: ； in, is the fixed rotation angle between the imaging plane and the measurement coordinate system, and are the azimuth unloading and pitch unloading before unspinning, respectively; and They are the azimuth unloading amount and the pitch unloading amount output to the coarse tracking simulation system after derotation; The off-axis reflective collimator is rotated in a predetermined direction to test whether the polarity of the azimuth unloading amount and the pitch unloading amount output by the fine tracking system to the coarse tracking simulation system is consistent with the protocol, and finally ensure that the polarity of the unloading amount is consistent with the protocol.

9. The performance testing method according to claim 8, characterized in that: The step three comprises: first, completing the communication test between the rough tracking platform dynamics simulation computer and the rough tracking platform management unit, and between the rough tracking platform management unit and the target simulated fast reflex mirror; completing the polarity and dimension calibration of the voltage value of the target simulated fast reflex mirror, so that the target simulated fast reflex mirror follows the azimuth output by the rough tracking platform dynamics simulation computer. and pitch angle Control the target to deflect to the desired pixel position on the image plane of the precision tracking system.

10. The performance testing method according to claim 9, characterized in that: The fourth step includes: when the fine tracking fast reflection mirror is in the open loop and closed loop states, the rough tracking platform dynamics simulation computer sends the azimuth and pitch angle The control target simulates the fast mirror movement and the coarse tracking error; the azimuth unloading amount output to the coarse tracking simulation system after derotation and pitch unloading Calibrate so that and .

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