A mirror target tracking constraint judgment method based on dynamic capability conversion

Abstract

This invention discloses a method for determining the constraints of rotating mirror target tracking based on dynamic capability conversion, relating to the field of rotating mirror target tracking control technology. The method includes: acquiring the current angle, deployment distance, maximum angular velocity, and maximum angular acceleration of the rotating mirror; dynamically converting the angular motion capability of the rotating mirror into the maximum linear velocity capability and maximum linear acceleration capability of the target plane edge points through geometric mapping; acquiring and comparing the current velocity and acceleration requirements of the edge points; determining that the velocity requirement exceeds the limit and stopping the corresponding process when the velocity requirement exceeds the limit; determining that the acceleration requirement exceeds the limit and performing amplitude limiting processing according to the capability upper limit before continuing to update. This invention can more realistically reflect the dynamic performance boundaries of the product and differentiate the processing of different types of super-capabilities, providing a constraint basis for theoretical trajectory generation, product capability verification, and trackability assessment.

Description

Technical Field

[0001] This invention relates to the field of servo control and target tracking technology, and in particular to a method for determining the constraints of rotating mirror target tracking based on dynamic capability conversion. Background Technology

[0002] In a rotating mirror target tracking system, the dynamic performance indicators of the servo turntable are typically given in the form of its maximum angular velocity and maximum angular acceleration of its rotation axis. When performing theoretical ballistic simulations or evaluating product tracking capabilities, a common practice is to directly compare the calculated angular velocity and angular acceleration requirements of the rotating mirror during tracking with the product's maximum angular velocity and maximum angular acceleration specifications. If the calculated angular velocity requirement exceeds the upper limit of the specification, the product is deemed insufficient to complete the tracking task; similarly, if the angular acceleration requirement exceeds the upper limit, it is also deemed unable to meet the tracking requirements. This judgment method directly relies on the physical limitations of the rotating mirror in the angular domain, and the calculation process is simple and intuitive, possessing a certain degree of operability in engineering.

[0003] The existing technical solutions have two significant drawbacks. First, the ultimate goal of the tracking system is to achieve stable imaging of the target on the detector surface, while the target's motion in physical space manifests as linear velocity and linear acceleration. Directly using angular velocity capability as a constraint fails to consider the nonlinear amplification effect of the mirror angle change on the image plane's motion velocity. Under certain large-angle conditions, even if the mirror's angular velocity is far below its physical upper limit, the linear velocity requirement at the target's edge points may already exceed the maximum equivalent linear velocity capability provided by the servo system, causing the target to deviate from the center of the field of view or even slide out of the field of view. This situation, where the angular velocity seems to be satisfied but the trajectory of the edge points has already deviated significantly, makes the constraint judgment based on the pure angle domain unable to accurately reflect the product's true tracking boundary. Second, the existing solutions have a simplistic logic when handling super-capabilities, failing to effectively distinguish between velocity exceeding limits and acceleration exceeding limits, two fundamentally different physical processes. When the target's maneuvering leads to excessive transient acceleration requirements, it may simply be that the servo system's instantaneous acceleration capability is insufficient; however, if the final velocity can be achieved, the system may still be able to contain the target within the field of view. Equating acceleration exceeding limits simply with tracking failure would lead to an overly conservative assessment of the product's actual tracking envelope, which is inconsistent with actual engineering control strategies. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a method for determining the constraints of rotating mirror target tracking based on dynamic capability conversion.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for determining the constraints of rotating mirror target tracking based on dynamic capability conversion includes the following steps: S1. Obtain the current angle of the rotating mirror, the maximum angular velocity of the rotating mirror, the maximum angular acceleration of the rotating mirror, and the station distance parameters.

[0006] S2. Based on the current angle of the rotating mirror, the maximum angular velocity of the rotating mirror, and the stationing distance, and according to a preset geometric mapping relationship, the angular velocity capability of the rotating mirror is dynamically converted into the maximum linear velocity capability of the edge point on the target plane.

[0007] S3. Based on the current angle of the rotating mirror, the maximum angular acceleration of the rotating mirror, the maximum angular velocity of the rotating mirror, and the stationing distance, and according to a preset geometric mapping relationship, the angular acceleration capability of the rotating mirror is dynamically converted into the maximum linear acceleration capability of the edge point on the target plane.

[0008] S4. Obtain the current velocity requirement and current acceleration requirement of the edge point, and compare them with the maximum linear velocity capability obtained in step S2 and the maximum linear acceleration capability obtained in step S3, respectively.

[0009] S5. When the current speed requirement of the edge point exceeds the maximum linear speed capability, it is determined that the speed exceeds the product capability, and the speed exceeds capability determination result is output. At the same time, the corresponding simulation process or trajectory generation process is stopped.

[0010] S6. When the current acceleration requirement of the edge point exceeds the maximum linear acceleration capability, it is determined that the acceleration exceeds the product capability, and the edge point velocity update process is limited according to the maximum linear acceleration capability, and the acceleration over-capacity determination result and the trajectory result after the limit update are output.

[0011] Furthermore, in step S2, the conversion formula for the maximum linear velocity capability of the edge point is:

[0012] in, The distance between stations, To rotate the camera to its current angle, This represents the maximum angular velocity of the rotating mirror.

[0013] Furthermore, in step S3, the conversion formula for the maximum linear acceleration capability of the edge point is:

[0014] in, This represents the maximum angular acceleration of the rotating mirror.

[0015] Furthermore, in step S4, the current acceleration requirement of the edge point is obtained by dividing the difference between the current velocity requirement and the actual velocity of the edge point at the previous sampling time by the sampling period.

[0016] Furthermore, at each sampling moment, based on the mirror rotation angle at the current sampling moment or the previous sampling moment, the maximum linear velocity capability and maximum linear acceleration capability of the target plane edge point are recalculated.

[0017] Furthermore, the method is applied to the target acquisition stage, target containment stage, or continuous tracking stage of a rotating mirror photoelectric search and tracking system.

[0018] The present invention has the following beneficial effects: 1. This invention dynamically maps the angular motion capability of the rotating mirror to the linear motion capability of the target plane edge points, making the constraint judgment model highly consistent with the actual working state of the product. Existing technologies only focus on the angular velocity limit of the rotating mirror axis system, ignoring the nonlinear amplification effect of the target image plane linear velocity caused by the change of the rotating mirror angle. This invention utilizes geometric relationships including secant functions to calculate in real time the limit linear velocity and limit linear acceleration that the edge points can withstand under the current rotating mirror swing angle. This conversion mechanism makes the constraint boundary no longer a fixed angular velocity value, but a linear velocity surface that dynamically changes with the system state. When the rotating mirror is in a large-angle scanning state, the secant square term increases sharply, and the equivalent linear velocity capability of the edge points decreases significantly. This invention can accurately identify this potential tracking failure risk and provide a more realistic and reliable quantitative basis for product capability boundary assessment.

[0019] 2. This invention achieves graded judgment and differentiated processing of speed overload and acceleration overload. The processing logic is more in line with the actual physical process in engineering. When it is judged as speed overload, it means that even if the servo system enters steady state, it cannot provide enough speed to keep the target in the field of view. This is an absolute hardware physical limit. Therefore, the method directly stops the corresponding simulation or control process to prompt the design change requirement. When it is judged as acceleration overload, it means that the system only has insufficient transient response speed, but there is still a margin in steady-state speed capability. At this time, the method does not interrupt the tracking process, but performs saturation limiting processing on the speed change according to the current maximum linear acceleration capability. This processing strategy simulates the real physical behavior of the servo driver when the current loop is saturated, avoids misjudging the system failure due to transient overshoot, and makes the constraint judgment result more consistent with the actual tracking envelope of the product.

[0020] 3. The method of this invention can be directly embedded into the pre-verification stage and online constraint update stage of theoretical trajectory generation. In the early stage of trajectory planning, the method of this invention can be used to quickly screen out the trajectory areas that cannot be covered due to insufficient product dynamic capabilities, guiding the adjustment of station distance or the allocation of performance indicators. In the real-time or semi-physical simulation process, the upper limit of linear motion capability is recalculated based on the updated rotating mirror angle at each sampling moment, and the edge point velocity is constrained iteratively. Since this method does not rely on complex iterative optimization algorithms and only involves algebraic operations and comparison logic, the computational load is extremely low. It is very suitable for embedded servo control systems or hardware-in-the-loop simulation platforms with extremely high real-time requirements to run as the underlying constraint module. At the same time, the amplitude limit update results output by this method can be directly used to correct and generate the driving rotating mirror servo commands. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating the overall process of a method for determining the constraints of rotating mirror target tracking based on dynamic capability conversion, as described in this invention. Figure 2 A schematic diagram illustrating the geometric relationship between the mirror rotation angle capability and the edge point linear velocity capability; Figure 3 A schematic diagram comparing edge point speed requirements with maximum linear speed capability; Figure 4 A schematic diagram comparing the acceleration requirements at edge points with the maximum linear acceleration capability; Figure 5 A flowchart illustrating the logic for determining the superpower rating; Figure 6 This is a schematic diagram comparing the output of the rotating mirror angle after constraint and amplitude limiting with the theoretical value. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0023] Example 1 This embodiment describes the specific implementation steps of a mirror target tracking constraint determination method based on dynamic capability conversion, with particular emphasis on the establishment of geometric mapping relationships and the derivation process of capability conversion formulas, so as to fully disclose the calculation basis involved in the claims.

[0024] Step 1: Initialization and parameter acquisition.

[0025] Get system deployment distance This distance is the vertical distance from the rotation center of the rotating mirror to the target motion plane. Obtain the maximum angular velocity specification of the servo turntable as specified by the manufacturer. and maximum angular acceleration index Read the current sampling time. Mirror rotation angle .

[0026] Step 2: Calculation of maximum linear velocity capability at edge points.

[0027] Establish the mapping relationship between the target plane position and the mirror angle. Let the one-dimensional coordinate axis on the target plane be... The rotation angle of the mirror is According to the law of optical reflection, when the mirror rotates... At an angle, the reflected light rotates. Angle, the mapped position on the target plane satisfy Taking the first derivative of this positional relationship yields the linear velocity of the target plane. With the angular velocity of the rotating mirror Relationship:

[0028] The maximum angular velocity that the product can provide Substituting the above relationship, we obtain the current angle. Maximum linear velocity capacity that the lower edge point can withstand :

[0029] Step 3: Calculation of maximum linear acceleration capacity at edge points.

[0030] Linear speed Further differentiating the expression yields the linear acceleration of the target plane. Relationship with the motion parameters of the rotating mirror angle:

[0031] in, The angular acceleration of the rotating mirror. This represents the current angular velocity of the rotating mirror. The limiting angular acceleration that the product can output. and limiting angular velocity Substituting this into the above equation, we obtain the maximum linear acceleration that the edge point can withstand under extreme motion conditions. :

[0032] Use absolute value symbol in formula This is to ensure the non-negativity of the upper limit of acceleration, because acceleration capability refers to the upper limit of the ability to change the magnitude of velocity, which is independent of the direction of motion.

[0033] Step 4: Requirements gathering and comparison.

[0034] Obtain the theoretical velocity requirement of the edge point calculated based on the target trajectory at the current moment. Calculate the acceleration requirement at the current moment. The calculation method is as follows:

[0035] in This represents the actual velocity of the edge point after constraint processing at the previous sampling time. The sampling period.

[0036] Step 5: Superpower rating and processing.

[0037] Compare and The size. If If the speed exceeds the product's capability, the system hardware is deemed unable to meet the speed requirement in any way. The system will then output a speed exceedance flag and terminate the current simulation stepping or trajectory generation process.

[0038] Compare and The size. If If the acceleration exceeds the product's capacity, the process is determined to be faulty. At this point, the method does not stop executing but instead enters the limiting process. First, the limiting value for the change in velocity is calculated. Then, the difference between the theoretical demand speed for this cycle and the actual speed for last week is clamped within a limit, thus obtaining the constrained speed for this cycle:

[0039] This embodiment clarifies the source and calculation relationship of each physical quantity in the formula by deriving the mapping formula for linear velocity and linear acceleration in detail, thus fully disclosing and supporting the limitations on the maximum linear velocity capability and maximum linear acceleration capability in the claims.

[0040] Example 2 This embodiment focuses on describing the details of the amplitude limiting process under the acceleration superpower condition, and explains the continuity of the trajectory after amplitude limiting, so as to support the relevant limitations on the amplitude limiting update result in the claims.

[0041] This embodiment follows steps 1 to 4 of Embodiment 1 to obtain the various parameters and required values. In step 5, for acceleration superpower, i.e. In this embodiment, a specific limit execution scheme is provided for the operating conditions.

[0042] To ensure that the velocity curve after clipping is physically feasible and smooth, this method employs a hard clipping strategy based on acceleration capability boundaries. When acceleration exceeds the capability, the method forcibly limits the actual velocity change at the edge points of the current cycle. Limited to the range Within. The specific calculation logic is as follows: Let the actual edge point velocity after constraint at the previous moment be... The theoretical speed requirement at this moment is Calculate the change in demand. The maximum allowable change in the system. .

[0043] like This indicates that the acceleration requirement is within our capabilities, so the actual speed this week... The system is tracking normally.

[0044] like If so, it is determined to be an acceleration superpower. The actual speed update for this week is:

[0045] After the above limiting process, the target angle corresponding to the rotating mirror will no longer be the angle calculated from the theoretical ballistics, but rather a feasible angle after dynamic capability constraint correction. In subsequent sampling moments... The method will be based on the corrected actual state. Continue calculating acceleration requirements Instead of using the ideal velocity of the theoretical trajectory, this feedback iteration mechanism ensures that the constraint determination is a dynamic process with memory, consistent with the response characteristics of real physical systems under saturation.

[0046] This embodiment further clarifies the algebraic implementation of acceleration limiting, avoids vague descriptions of the limiting process, and ensures that the technical feature of limiting the edge point update process according to the maximum linear acceleration capability in the claims can be clearly supported.

[0047] Example 3 This embodiment describes the complete workflow of applying the method of the present invention to a high-speed medium-wave thermal imaging rotating mirror target tracking system, especially the specific application of dynamic capability conversion in the target acquisition, containment and continuous tracking stages.

[0048] The application scenario is set as follows: a mid-wave infrared thermal imager equipped with a two-dimensional rotating mirror servo mechanism searches for and tracks high-speed moving targets in distant airspace. System deployment distance... The maximum angular velocity of the rotating mirror is 5000 meters. 4 radians per second, maximum angular acceleration The interval is 20 radians per second squared. The target performs a near-linear lateral maneuver in a plane perpendicular to the optical axis.

[0049] During the target acquisition phase, the system first points to the predicted airspace based on guidance information. When the target first appears at the edge of the field of view, the servo system immediately enters the acquisition state. At this time, utilizing steps S2 and S3 of the present invention, the system determines the target based on the current initial pointing angle. Calculate the current equivalent maximum linear velocity and linear acceleration capabilities of the edge points in the field of view. Also calculate the velocity requirements of the edge points when the target crosses the field of view. Exceeding the calculated amount The system will issue a speed over-limit warning the moment it is intercepted, indicating to the operator that the target trajectory has exceeded the physical tracking envelope of the rotating mirror product and there is no need to attempt to switch to automatic tracking.

[0050] During the target containment phase, the target may be located at the edge of the field of view and moving towards the center. The servo system needs to drive the rotating mirror to pull the target back to the center of the field of view. In this process, the system repeats steps 1 to 5 of Embodiment 1 within each servo cycle, for example, 1 millisecond. Let the current rotating mirror angle be... The value is 30 degrees. Substituting it into the formula, we get... and If caused by the target's sudden acceleration Exceeded The system automatically applies acceleration limiting. Specifically, the rotating mirror cannot immediately reach a high rotation speed according to the theoretical trajectory, but instead smoothly accelerates at maximum acceleration capability. Although this causes the target's position on the target surface to temporarily lag behind the center of the field of view, this lag is controlled, and the tracking process will not be interrupted as long as the target does not slip out of the field of view boundary. This characteristic allows the system to maintain target containment even in the event of transient acceleration saturation.

[0051] During the continuous tracking phase, the target may perform continuous, strong maneuvering turns. The method of this invention recalculates the maximum linear velocity and maximum linear acceleration capabilities of the target plane edge points at each sampling time, based on the mirror rotation angle at the current or previous sampling time. When the mirror rotation angle approaches its limit operating range, such as within ±40 degrees, due to… The sharp increase in the number of terms, the linear velocity capability of the edge points The capability will decrease significantly. The method of this invention can capture this capability decay trend in real time. If the target is still moving at high speed at this time, the system will trigger a speed over-limit judgment near the capability boundary in advance, thereby avoiding target loss or hardware damage caused by the rotating mirror hitting the mechanical limit.

[0052] As can be seen from this embodiment, the method of the present invention not only provides judgment logic, but also provides a full-process, adaptive dynamic constraint mechanism, which provides solid technical support for the trackability evaluation and online control of the rotating mirror tracking system.

[0053] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for determining the constraints of rotating mirror target tracking based on dynamic capability conversion, characterized in that, Includes the following steps: S1. Obtain the current angle of the rotating mirror, the maximum angular velocity of the rotating mirror, the maximum angular acceleration of the rotating mirror, and the station placement distance; S2. Based on the current angle of the rotating mirror, the maximum angular velocity of the rotating mirror, and the stationing distance, and according to a preset geometric mapping relationship, the angular velocity capability of the rotating mirror is dynamically converted into the maximum linear velocity capability of the edge point on the target plane. S3. Based on the current angle of the rotating mirror, the maximum angular acceleration of the rotating mirror, the maximum angular velocity of the rotating mirror, and the stationing distance, and according to a preset geometric mapping relationship, the angular acceleration capability of the rotating mirror is dynamically converted into the maximum linear acceleration capability of the edge point on the target plane. S4. Obtain the current velocity requirement and current acceleration requirement of the edge point, and compare them with the maximum linear velocity capability and the maximum linear acceleration capability, respectively. S5. When the current speed requirement of the edge point exceeds the maximum linear speed capability, it is determined that the speed exceeds the product capability, and the speed exceeds capability determination result is output. S6. When the current acceleration requirement of the edge point exceeds the maximum linear acceleration capability, it is determined that the acceleration exceeds the product capability, and the edge point update process is limited according to the maximum linear acceleration capability, and the acceleration over-capacity determination result and the limited update result are output.

2. The method according to claim 1, characterized in that, In step S2, the maximum linear velocity capability of the edge point satisfies: in, The distance between the stations is mentioned. The current angle of the rotating mirror. The maximum angular velocity of the rotating mirror is given.

3. The method according to claim 1, characterized in that, In step S3, the maximum linear acceleration capability of the edge point satisfies: in, The distance between the stations is mentioned. The current angle of the rotating mirror. The maximum angular velocity of the rotating mirror. Let be the maximum angular acceleration of the rotating mirror.

4. The method according to claim 1, characterized in that, In step S4, the current acceleration requirement of the edge point is calculated by dividing the difference between the current velocity requirement and the actual velocity of the edge point at the previous sampling time by the sampling period.

5. The method according to claim 1, characterized in that, Step S5 further includes: when it is determined that the speed exceeds the product's capability, stopping the corresponding simulation process or trajectory generation process.

6. The method according to claim 1, characterized in that, In step S6, the limiting process for the edge point update process according to the maximum linear acceleration capability specifically involves limiting the actual velocity change of the edge points in the current sampling period to a limit value determined by the product of the maximum linear acceleration capability and the sampling period.

7. The method according to any one of claims 1 to 6, characterized in that, At each sampling moment, based on the mirror rotation angle at the current sampling moment or the previous sampling moment, the maximum linear velocity capability and maximum linear acceleration capability of the target plane edge point are recalculated.

8. The method according to any one of claims 1 to 6, characterized in that, The method is applied to the target acquisition phase, target containment phase, or continuous tracking phase of a rotating mirror photoelectric search and tracking system.

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