Multi-section self-adaptive centering control method for ATP turntable tracking

Abstract

The invention relates to a multi-stage self-adaptive centering control method for ATP turntable tracking, which belongs to the technical field of ATP tracking control, and comprises the following steps of: 1, dividing a centering control area into a quick in-place area, a self-adaptive buffer area and a switching tracking area; step 2, first-section type memory tracking is adopted in the rapid in-place area, so that the rotary table rapidly gets close to the target; 3, adjusting the speed of a turntable in the adaptive buffer area based on a target size and focal length value fusion strategy to avoid image pasting; 4, an image delay correction tracking strategy is adopted in the switching tracking area, and the tracking precision is guaranteed; the method has the beneficial effects that through a mode of combining the quick in-place area, the self-adaptive buffer area and the switching tracking area, the centering speed of the rotary table is improved, and meanwhile, the target is prevented from being lost.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of ATP tracking control, and particularly relates to a multi-section adaptive homing control method for ATP turntable tracking. BACKGROUND

[0002] With the development of unmanned aerial vehicle technology, the demand for countermeasures against unmanned aerial vehicles is also increasingly strong. In the rapid countermeasures against unmanned aerial vehicles, in addition to the high-precision unmanned aerial vehicle tracking technology, a technology capable of quickly switching the device into a tracking state is also needed to improve the response speed of the entire process. In the field of image tracking, if the target homing speed is too fast, the image will be in a blurred state, so that the ATP turntable loses the target. If the target is to be homed clearly, the homing speed must not be fast, so these two points are contradictory.

[0003] The prior art generally adopts the measure of directly limiting the homing speed, so that the image is not blurred during the homing process, but the homing speed is still slow, and it shows poor compatibility for different focal lengths and different sizes of targets, and it is difficult to achieve the purpose of improving the rapidity of homing and ensuring that the target is not lost during the homing process. Therefore, how to improve the homing speed while ensuring that the target is not lost remains to be further solved. SUMMARY

[0004] The application provides a multi-section adaptive homing control method for ATP turntable tracking, which is used to solve the technical problem of how to improve the homing speed while ensuring that the target is not lost, and improves the turntable homing speed while ensuring that the target is not lost.

[0005] In order to achieve the above purpose, the application realizes the following technical scheme:

[0006] A multi-section adaptive homing control method for ATP turntable tracking, comprising the following steps:

[0007] Step 1: dividing the homing control region into a fast-to-position area, an adaptive buffer area and a switching tracking area, and realizing smooth transition of speed through the intervention of the adaptive buffer area between the fast-to-position area and the adaptive buffer area;

[0008] Step 2: adopting first-section memory tracking in the fast-to-position area to make the turntable quickly approach the target;

[0009] Step 3: adjusting the turntable speed based on the target size and focal length value fusion strategy in the adaptive buffer area to avoid image blurring;

[0010] Step 4: adopting image delay correction tracking strategy in the switching tracking area to ensure tracking accuracy.

[0011] Optionally, in step 1, the speed smooth transition is realized by the early intervention of the adaptive buffer between the fast-to-position area and the adaptive buffer, which can effectively prevent the jitter in the centering process and make the image tracking lose the target.

[0012] Optionally, in step 2, the fast-to-position area uses the effective azimuth and the pitch off-target amount and the azimuth angle and the pitch angle of the turntable to perform target polar coordinate mapping, so that the turntable quickly approaches the target point in a guided manner.

[0013] Optionally, the target polar coordinate mapping is as follows formula (1):

[0014] (1);

[0015] wherein, , is the pitch off-target amount, and the azimuth angle of the turntable, is the pitch angle; , are the target azimuth and pitch polar coordinate position amounts respectively; is the camera pixel size; is the focal length value.

[0016] Optionally, in step 3, the turntable tracking speed is adjusted in real time online by using the strategy of integrating the target size and the focal length value, so as to ensure that the image tracking target is not blurred, according to the target size and the focal length value, the image target is not easy to lose, and the target is small and the focal length is large, the target is easy to lose, and the speed limiting strategy is designed as shown in formula (2):

[0017] (2);

[0018] wherein, is the output speed limiting amount, is the speed intersection amount with the fast-to-position area, is the target area, is the adjustment coefficient, is the minimum speed, is the focal length value.

[0019] Optionally, the adjustment coefficient will be optimized online by particle swarm according to the target motion speed, and the tracking error and the output speed limiting amount are taken as indexes, and 50 frames of data are taken as an update period to establish a target function as follows formula (3):

[0020] (3);

[0021] Wherein, a, b are weight coefficients, T is control period.

[0022] Optionally, in step 4, the turntable tracking position point will reach the vicinity of the target position, and the turntable quickly tracks the turntable tracking position point to realize the whole homing tracking process.

[0023] Optionally, since the target position information quantity has a large time delay in the processing and transmission process, the time delay is compensated, and a direct prediction method is used to compensate the delay link.

[0024] Optionally, the direct prediction method compensating the delay link is as follows formula (4):

[0025] (4);

[0026] To make , the compensation link is , the lag compensation is as follows formula (5): ; Wherein, is the target information quantity, is the lag information quantity, is the compensated information quantity, is the delay time, and s is the target area.

[0027] Optionally, The Taylor expansion of is as follows formula (7):

[0028] (7);

[0029] Wherein, the more the series expansion, the more accurate the compensation, and due to the existence of the target area s, the more the expansion series, the more noise introduced, The Taylor expansion of is taken as three terms.

[0030] The beneficial effects of the present application are:

[0031] The present application forms a multi-section adaptive homing control method by designing a fast-to-position area, an adaptive buffer area and a switching tracking area in combination, the fast-to-position area makes the turntable quickly position, the adaptive buffer area makes the turntable have the performance of ensuring image tracking without being blurred under any working condition, and the switching tracking area ensures the tracking accuracy of the turntable. BRIEF DESCRIPTION OF DRAWINGS

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the workflow of the present invention;

[0034] Figure 2 This is a schematic diagram of the multi-segment adaptive centering algorithm of the present invention;

[0035] Figure 3 This is a schematic diagram of the turntable speed output of the present invention;

[0036] Figure 4 This is a schematic diagram illustrating the compensation principle of the compensation delay stage in this invention;

[0037] Figure 5 This is a schematic diagram of the overall compensation principle of the compensation delay stage of the present invention. Detailed Implementation

[0038] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0039] Example 1

[0040] like Figure 1 As shown, this embodiment provides a multi-segment adaptive homing control method for ATP turntable tracking, including the following steps:

[0041] Step 1: Divide the centering control area into a fast arrival zone, an adaptive buffer zone, and a switching tracking zone, and achieve a smooth speed transition between the fast arrival zone and the adaptive buffer zone through the intervention of the adaptive buffer zone;

[0042] Step 2: Use first-segment memory tracking in the rapid positioning zone to make the turntable quickly approach the target;

[0043] Step 3: Adjust the turntable speed in the adaptive buffer based on a strategy that combines target size and focal length to avoid image blurring;

[0044] Step 4: Use an image delay correction tracking strategy in the switching tracking area to ensure tracking accuracy.

[0045] A unique multi-section adaptive homing control method is formed by combining a fast homing zone, an adaptive buffer zone and a switching tracking zone. The fast homing zone adopts a first-section memory tracking mode to make the turntable fast homing. The adaptive buffer zone adopts a strategy of fusing the target size and the focal length value to ensure the image tracking performance under any working condition. The switching tracking zone adopts an image delay correction tracking strategy to ensure the tracking accuracy. Figure 2 As shown in FIG. 1, in step 1, the adaptive buffer zone is intervened in advance between the fast homing zone and the adaptive buffer zone to ensure the performance of smooth transition of speed and effectively prevent the shaking in the homing process, so that the image tracking does not lose the target.

[0046] Embodiment 2

[0047] Based on embodiment 1, in step 2, the fast homing zone is designed by using the target azimuth and pitch off-target amount 、 obtained for the first time, the target polar coordinate mapping is performed on the azimuth angle and the pitch angle of the turntable, and the target polar coordinate mapping relationship is shown in formula (1):

[0048] (1);

[0049] wherein, and are the target azimuth and pitch polar coordinate position amounts, respectively; is the camera pixel size, and the unit is ;is the focal length value, and the unit is . After obtaining the target azimuth and pitch polar coordinate position amounts, the turntable fast approaches the target point in a guided manner, and this region can be completely unaffected by the image tracking to ensure the rapidity of homing. As shown in FIG. 2, when the speed of the turntable is reduced to the upper limit of the second stage speed, the process of this stage is ended. Embodiment 3 Figure 3 Based on embodiment 1, in step 3, the adaptive buffer zone is designed by using the strategy of fusing the target size and the focal length value to adjust the tracking speed of the turntable in real time to ensure that the image tracking target is not blurred. Because the target is large and the focal length is short, the image target is not easy to lose, while the target is small and the focal length is large, the target is easy to lose. Therefore, the speed limiting strategy shown in formula (2) is designed:

[0050] (2);

[0051] wherein, is the output speed limiting amount, and is the target size.

[0052]

[0053] ​​​​For the rapid to the intersection of the area speed volume, For the target area, unit: cm 2 , For the adjustment coefficient, For the minimum speed, output schematic diagram as Figure 3 shown. Adjustment coefficient will be adjusted with the target motion speed through Particle Swarm Optimization (PSO) online optimization to track the error and output speed as an indicator, 50 frames of data as the update cycle, the objective function as follows formula (3):

[0054] (3);

[0055] Wherein, a, b is the weight coefficient, T is the control cycle.

[0056] Example 4

[0057] Based on example 1, when the two stage processing of step 2 and step 3 is completed, in step 4, the turntable tracking position point will reach the target position near, the turntable quickly tracking turntable tracking position point, to realize the whole process of homing tracking. Because the target position information quantity in the process of processing and transmission will exist larger time delay, to the servo tracking caused not small influence, therefore need to a certain amount of compensation for time delay. Kalman filter is the turntable tracking platform commonly used time delay compensation method, but it needs signal dynamic characteristics and noise statistics characteristics to determine, however, the actual situation is not determined, therefore, limit the compensation effect, therefore, the direct prediction method is used to compensate the delay link, compensation principle as Figure 4 shown, wherein, is the target information quantity, is the lag information quantity, is the compensated information quantity, is the delay time.

[0058] The direct prediction method compensates the delay link as follows formula (4):

[0059] (4);

[0060] To make , need to compensate the link , lag compensation as follows formula (5): ; wherein, is the target information quantity, is the lag information quantity, is the compensated information quantity, is the delay time, s is the target area, is a delay link.

[0061] wherein, The Taylor expansion of is formula (6): (6);The more the series expansion, the more accurate the compensation, but due to the existence of target area s (differential), the more the expansion series, the more noise introduced, so take the first three, that is, formula (7): (7);

[0062] Substitute formula (7) into formula (5), formula (8) is obtained: (8);wherein, is a first-order derivative of the lag information amount, is a second-order derivative of the lag information amount. The compensation delay link is shown in Figure 5 , the filter in Figure 5 is a first-order low-pass filter, which not only has the characteristics of simple implementation, but also has the advantage of easy debugging.

[0063] Example 5

[0064] Based on all the above examples, the same experimental turntable is used for testing, and the centering comparison experiment is carried out at 1 / 5, 1 / 4, 1 / 3 and 1 / 2 of the target distance field center, respectively. The experimental results are shown in Table 1.

[0065] Table 1 Centering comparison experiment table

[0066]

[0067] From Table 1, it can be seen that the strategy not only realizes the performance of fast centering, but also improves the range and success rate of the centering area, effectively verifying the feasibility of the strategy.

[0068] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any skilled person in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A multi-segment adaptive homing control method for ATP turntable tracking, characterized in that, Comprise the following steps: Step 1: divide the homing control area into fast-to-position area, adaptive buffer area and switching tracking area, and realize smooth transition of speed through the intervention of adaptive buffer area between fast-to-position area and adaptive buffer area; Step 2: in the fast-to-position area, first segment type memory tracking is adopted to make the turntable quickly approach the target; Step 3: in the adaptive buffer area, the speed of the turntable is adjusted based on the target size and focal length value fusion strategy to avoid image blur; Step 4: in the switching tracking area, image delay correction tracking strategy is adopted to ensure tracking accuracy.

2. The multi-segment adaptive homing control method for ATP turntable tracking according to claim 1, wherein, In the step 1, the smooth transition of speed is realized through the advance intervention of the adaptive buffer area between the fast-to-position area and the adaptive buffer area, which can effectively prevent the shaking during the homing process and make the image tracking lose the target.

3. The multi-segment adaptive homing control method for ATP turntable tracking according to claim 1, wherein, In the step 2, the target polar coordinate mapping is performed using the first obtained effective azimuth, pitch off-target amount and turntable azimuth angle, pitch angle to make the turntable quickly approach the target point in a guided manner.

4. The multi-segment adaptive homing control method for ATP turntable tracking according to claim 3, characterized in that, The target polar coordinate mapping is as follows formula (1): (1)； wherein, , is a pitch miss distance, and a turntable azimuth, is a pitch angle; , are a target azimuth, pitch polar coordinate position quantity, respectively; is a camera pixel size; is a focal length value.

5. The method of claim 1, wherein, In the step 3, the target size and focal length value fusion strategy is used to adjust the turntable tracking speed in real time to ensure that the image tracking target does not blur, according to the target size and focal length value fusion strategy, the speed limit strategy is designed as shown in the following formula (2): (2)； wherein, is an output speed limit amount, is a fast-in-place area speed intersection amount, is a target area, is an adjustment coefficient, is a minimum speed, is a focal length value.

6. The multi-segment adaptive homing control method for ATP turntable tracking according to claim 5, wherein, The adjustment coefficient Online optimization is performed through the particle swarm along with the target motion speed to track the error The output speed limit amount As an index, a target function is established with 50 frames of data as an update cycle Is as follows formula (3): (3)； Wherein, a, b are weight coefficients, T is control period.

7. The multi-segment adaptive homing control method for ATP turntable tracking according to claim 1, wherein, In the step 4, the turntable tracking position point will reach the vicinity of the target position, and the turntable quickly tracks the turntable tracking position point to realize the whole homing turn tracking process.

8. The multi-segment adaptive homing control method for ATP turntable tracking according to claim 7, characterized in that, Since there is a large time delay in the processing and transmission of target position information, the time delay is compensated, and the direct prediction method is used to compensate the delay link.

9. The multi-segment adaptive homing control method for ATP turntable tracking according to claim 8, wherein, The direct prediction method for compensating the delay link is as follows formula (4): (4)； To make , the compensation link is , the lag compensation is as follows formula (5): ; wherein, is the target information quantity, is the lag information quantity, is the compensated information quantity, is the delay time, and s is the target area.

10. The method of claim 9, wherein, The Taylor expansion of the following equation (7): (7)； The more the series expansion, the more accurate the compensation. Since the target area s exists, the more the series expansion, the more the noise introduced, The Taylor expansion is taken to three terms.

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