Optimal path calculation method for converting high-speed search process into tracking process of photoelectric system

Abstract

The invention provides an optimal path calculation method for converting a high-speed search process into tracking of a photoelectric system, and belongs to the field of automatic control of photoelectric systems. According to the method, a path for switching the photoelectric system from a high-speed search process to a tracking state is planned into two paths, one path is that the photoelectric system always moves forwards from a current position, and the other path is that the photoelectric system slows down to a zero position from the current position and then turns to move backwards. When the state needs to be converted into a tracking state, firstly, a target angle is converted into an azimuth position of a target in a photoelectric coordinate system through coordinate conversion, and then the relative relation between the current azimuth position of the photoelectric system and the azimuth position of the target is calculated; the optimal path is selected from the two planned paths by combining the travel difference between the two paths with the searching speed of the photoelectric system and the planned turning speed and acceleration, so that the optimal path from the high-speed searching process to the tracking process can be calculated in real time, and the response time of the photoelectric system is effectively shortened.

Description

Technical Field

[0001] The present invention belongs to the technical field of automatic control of photoelectric systems, and in particular relates to an optimal path calculation method for high-speed search process-to-tracking of a photoelectric system. Background Art

[0002] With the development of modern technology, optoelectronic systems have gradually transformed from tracking devices that can only passively receive target indications to integrated devices that can autonomously search and track.

[0003] The increasing speed and maneuverability of targets are placing higher demands on the efficiency and response time of optoelectronic systems in target detection. The process from target search to stable tracking is complex, and multiple factors influence response speed. Limited by the integrated search and tracking architecture of optoelectronic systems, increased search speed is essential to improve target detection efficiency. However, the higher the search speed, the longer it takes to transition to tracking during high-speed search. Improving the response time of optoelectronic systems for high-speed, maneuvering targets has become a pressing need.

[0004] Current methods for transitioning from high-speed search to tracking in optoelectronic systems often involve first stopping the search process, then reorienting based on target information, and finally acquiring and tracking the target. While this method offers the fastest transition from search to tracking under certain conditions, it often takes a significant amount of time. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem of long time consumption in the method of switching to tracking during the high-speed search process of the optoelectronic system in the prior art, and to provide an optimal path calculation method for the switching to tracking during the high-speed search process of the optoelectronic system. The method calculates the relative relationship between the orientation position of the optoelectronic system and the target position during the search process in real time, and calculates the optimal path for the switching to tracking during the high-speed search process in real time through the travel difference between the two, and combines the search speed of the optoelectronic system and the planned turning speed and acceleration, which can effectively shorten the response time of the optoelectronic system.

[0006] To achieve the above objectives, the technical solutions provided by the present invention are:

[0007] A method for calculating an optimal path for high-speed search and tracking of an optoelectronic system is provided, comprising the following steps:

[0008] Step 1: Obtain the target angle, target distance, and target tracking instructions, and obtain the azimuth angle β of the optoelectronic system, where the target angle is the coordinate of the target in the carrier-stabilized coordinate system or the earth-stabilized coordinate system, and includes the target azimuth angle β0 and the pitch angle ε0;

[0009] Step 2: Calculate the azimuth angle β and elevation angle ε of the target in the photoelectric coordinate system using coordinate transformation according to the obtained target angle and target distance;

[0010] Step 3: Establish the time equations for the two paths of the optoelectronic system transitioning from the high-speed search process to the tracking state. The first path is that the optoelectronic system moves forward from the current position, first moves at a constant speed at the search speed, then decelerates to zero, and reaches the target position. The time required is t1. The second path is that the optoelectronic system decelerates from the current position at the search speed to the zero position, then turns around and moves in the opposite direction, first accelerates to the maximum turning speed, then moves at a constant speed, and finally decelerates to zero. The time required is t2:

[0011]

[0012] Where V s is the search speed of the optoelectronic system, a t is the acceleration of the photoelectric system, S1 is the angular travel of the photoelectric system from the search speed to zero, S2 is the angular travel of the photoelectric system moving to the target position through the first path, V t is the maximum turning speed of the photoelectric system, S3 is the angular stroke of the photoelectric system in the second path from deceleration to zero position to reverse movement to the target position, S4 is the angular stroke of the photoelectric system from the maximum turning speed to zero, S2-S1+S3=360°;

[0013] Step 4: Assume that the time t1 required for the photoelectric system to select the first path is equal to the time t2 required for the second path. Use the time equation established in step 3 to calculate the angular travel S2 of the photoelectric system to the target position via the first path:

[0014]

[0015] Step 5: Select the optimal path based on the relationship between the difference between the azimuth angle β of the optoelectronic system and the azimuth angle β of the target in the optoelectronic system coordinate system and the angular travel S2 calculated in step 4, so as to minimize the reaction time of the optoelectronic system from the high-speed search process to the tracking state:

[0016] If β, -β<S2, then choose the first path;

[0017] If β, -β>S2, then choose the second path;

[0018] If β, -β = S2, the two paths take the same amount of time and either path can be chosen arbitrarily.

[0019] Furthermore, in step 5, if β, -β < S1, it means that the optoelectronic system has exceeded the target position when decelerating from the high-speed search state to zero and needs to turn in the opposite direction. In this case, the second path is selected.

[0020] Furthermore, step 2 includes the following sub-steps:

[0021] Step 2.1, convert the target angle from polar coordinates to rectangular coordinates:

[0022]

[0023] Where x, y, and z are the rectangular coordinates of the target in the carrier's stable coordinate system or the earth's stable coordinate system, and R is the target distance;

[0024] Step 2.2, convert the target rectangular coordinates from the carrier stable coordinate system or the earth stable coordinate system to the photoelectric coordinate system:

[0025]

[0026] Where x, y, and z are the rectangular coordinates of the target in the photoelectric coordinate system, ψ is the carrier pointing angle, θ is the roll angle, and φ is the pitch angle.

[0027] Step 2.3, convert the target rectangular coordinates in the photoelectric coordinate system into polar coordinates:

[0028]

[0029] Furthermore, the target angle is a coordinate in a stable coordinate system of the carrier, ψ=0.

[0030] The advantages of the present invention are:

[0031] The present invention proposes a method for calculating the optimal path for transitioning from a high-speed search process to tracking in an optoelectronic system. This method plans two paths for transitioning from a high-speed search process to a tracking state: one involves continuous forward motion from the current position, and the other involves first decelerating from the current position to zero and then turning and moving in the opposite direction. In both paths, the optical axis points toward the target when the optoelectronic system's speed is zero, completing the transition from the search state to the tracking state. When the optoelectronic system receives a tracking instruction during the search process, it calculates the relative relationship between the system's current azimuth position and the target's azimuth position. The optimal path is selected from the two planned paths based on the difference in travel distance between the two, combined with the optoelectronic system's search speed and the planned turning speed and acceleration. Consequently, the present invention can calculate the optimal path for transitioning from a high-speed search process to tracking in real time, effectively shortening the optoelectronic system's response time. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or other features and advantages of the present invention will become more readily understood through the following description with reference to the accompanying drawings, in which:

[0033] Figure 1 This is a schematic diagram of path planning in the optimal path calculation method for high-speed search and tracking of an optoelectronic system according to the present invention;

[0034] Figure 2 It is a schematic diagram of the coordinate system in the present invention. DETAILED DESCRIPTION

[0035] The present invention will be described in detail below with reference to the accompanying drawings by means of exemplary embodiments of the present invention. It should be noted that the following detailed description of the present invention is only for the purpose of illustration and is not intended to limit the present invention.

[0036] It should be pointed out that, in the context of the present invention, the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "inside", "outside", "clockwise" and "counterclockwise" etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention.

[0037] Furthermore, terms such as "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or to implicitly indicate the quantity of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features.

[0038] This invention provides a method for calculating the optimal path for high-speed tracking during an optoelectronic system's search process. By calculating the optoelectronic system's own azimuth position and target position in real time, combined with its search speed, this method optimizes the tracking path and improves system response time. The optoelectronic search system primarily searches in azimuth, with elevation remaining in standby mode. This calculation method primarily focuses on azimuth, and the following description will only address this direction.

[0039] In the present invention, the current azimuth position of the optoelectronic system is acquired in real time during the search process. The target azimuth position is received simultaneously with the tracking instruction. The received target azimuth position is typically in the optoelectronic system carrier coordinate system, and calculations require conversion to the optoelectronic system. In the present invention, the optoelectronic system azimuth is defined as positive if it rotates clockwise.

[0040] The optoelectronic system high-speed search process turns the optimal path of tracking into the optimal path according to the travel difference between the real-time position of the optoelectronic system and the target position, through the search speed V s , turn speed Vt and the rotation acceleration a t Calculating the angular travel of the photoelectric system can be divided into two motion paths, as shown in the schematic diagram Figure 1 :

[0041] The first path continues to move forward at the search speed. When the distance between the real-time position of the photoelectric system and the target position is When the speed reaches zero, the optical axis points to the target.

[0042] The second path first changes the search speed to acceleration-a t Slow down to zero, then turn according to the path planned by the optoelectronic system. After turning into position, the optoelectronic system speed is zero and the optical axis points to the target.

[0043] The optimal path calculation method for the high-speed search process to tracking of the optoelectronic system provided by the present invention is now described in detail.

[0044] The optimal path calculation method for high-speed search and tracking of an optoelectronic system provided by the present invention comprises the following steps:

[0045] Step S1, obtaining a target angle, a target distance, and a target tracking instruction, and obtaining an azimuth angle β of the optoelectronic system, wherein the target angle is the coordinate of the target in a carrier-stabilized coordinate system or an earth-stabilized coordinate system, and includes a target azimuth angle β0 and a pitch angle ε0;

[0046] Step S2, calculating the azimuth angle β and the pitch angle ε of the target in the photoelectric coordinate system by using coordinate transformation according to the obtained target angle and target distance;

[0047] Step S3, establish the time equations required for the photoelectric system to switch from the high-speed search process to the tracking state. The first path is that the photoelectric system moves forward from the current position A, first moves at a constant speed at the search speed, then decelerates to zero, and then reaches the target position C. The time required is t1. The second path is that the photoelectric system first decelerates at the search speed to the zero position B from the current position A, then turns around and moves in the opposite direction, first accelerates to the maximum turning speed, then moves at a constant speed, and finally decelerates to zero. At this time, it reaches the target position C. The time required is t2:

[0048]

[0049] Where V s is the search speed of the optoelectronic system, a t is the acceleration of the photoelectric system, S1 is the angular stroke of the photoelectric system from the search speed of the current position A to the zero position B, which is a known value, and S2 is the angular stroke of the photoelectric system from the current position A to the target position C through the first path, V tis the maximum turning speed of the photoelectric system, S3 is the angular stroke of the photoelectric system in the second path from deceleration to zero position B to reverse movement to the target position C, and S4 is the angular stroke of the photoelectric system from the maximum turning speed to zero, which are known values:

[0050]

[0051]

[0052] S2-S1+S3=360° (5)

[0053] In step S4, the time t1 required for the optoelectronic system to select the first path and the time t2 required for the second path are set equal, and the following formula can be obtained:

[0054] t1=t2 (6)

[0055] According to equations (1), (2), (5) and (6), the angular travel S2 of the photoelectric system moving to the target position through the first path is calculated:

[0056]

[0057] In step S5, the optimal path is selected based on the relationship between the difference between the azimuth angle β of the optoelectronic system and the azimuth angle β of the target in the optoelectronic system coordinate system, and the angular travel S2 calculated in step S4, so as to minimize the reaction time of the optoelectronic system from the high-speed search process to the tracking state. According to the azimuth turnover characteristic of the optoelectronic system, the maximum difference between the two angles is 360°. In addition, during the calculation, the difference between the two angles needs to be converted to a range of 0° to 360°. The conversion formula is:

[0058] If β,-β<0, then β,-β=β,-β+360.

[0059] The optimal path selection method is as follows:

[0060] If β, -β<S2, then choose the first path;

[0061] If β, -β>S2, then choose the second path;

[0062] If β, -β = S2, the two paths take the same amount of time and either path can be chosen arbitrarily.

[0063] There is a special case: if β, -β < S1, this means that the optoelectronic system has already passed the target when decelerating from the high-speed search state to zero, and therefore needs to reverse. In this case, the second path is selected. Using the above process, the optimal path from high-speed search to tracking can be calculated in real time.

[0064] In some embodiments of the present invention, Figure 2 As shown, step S2 includes the following sub-steps:

[0065] Step S2.1, convert the target angle from polar coordinates to rectangular coordinates:

[0066]

[0067] Where x, y, and z are the rectangular coordinates of the target in the carrier's stable coordinate system or the earth's stable coordinate system, and R is the target distance;

[0068] Step S2.2, convert the target rectangular coordinates from the carrier stable coordinate system or the earth stable coordinate system to the photoelectric coordinate system:

[0069]

[0070] Where x, y, and z are the rectangular coordinates of the target in the photoelectric coordinate system, ψ is the carrier pointing angle, θ is the roll angle, and φ is the pitch angle. If the target angle is the coordinate in the carrier's stable coordinate system, then ψ = 0.

[0071] Step S2.3, convert the target rectangular coordinates in the photoelectric coordinate system into polar coordinates:

[0072]

[0073] Next, the optimal path calculation method for high-speed search and tracking of an optoelectronic system provided by the present invention will be further described with reference to examples.

[0074] In this example, the optoelectronic system searches for a speed V s =180° / s, maximum rotation speed V t =150° / s, acceleration a t =400° / s 2 Calculation shows: S1 = 40.5°, S4 = 28.125°, S2 = 267.545°.

[0075] When β, -β<267.545°, the first path is selected; if β, -β>267.545°, the second path is selected; if β, -β=267.545°, either path can be selected; similarly, if β, -β<40.5°, it means that when the optoelectronic system decelerates from the high-speed search state to zero, it has exceeded the target position and needs to turn in the opposite direction, so the second path is selected. Thus, the optimal path for the optoelectronic system to switch from the search process to the tracking state is selected.

[0076] Therefore, as described above, according to the present invention, when the optoelectronic system receives a tracking instruction during the search process, it first uses coordinate conversion to convert the target angle into the azimuth position of the target in the optoelectronic coordinate system, and then calculates the relative relationship between the current azimuth position of the optoelectronic system and the target azimuth position. The optimal path is selected from the two planned paths through the travel difference between the two combined with the search speed of the optoelectronic system and the planned turning speed and acceleration. Therefore, the present invention can calculate the optimal path for high-speed search process to tracking in real time, which can effectively shorten the response time of the optoelectronic system.

[0077] Finally, it should be noted that the features mentioned and / or illustrated in the above description of the exemplary embodiments of the present invention may be incorporated into one or more other embodiments in the same or similar manner, combined with features in other embodiments, or substituted for corresponding features in other implementations. The technical solutions obtained by such combination or substitution shall also be deemed to be included in the scope of protection of the present invention.

Claims

1. A method for calculating the optimal path for high-speed search and tracking of an optoelectronic system, characterized in that: The following steps are involved: Step 1: Obtain the target angle, target distance, and target tracking instructions, and obtain the azimuth angle β of the optoelectronic system, where the target angle is the coordinate of the target in the carrier-stabilized coordinate system or the earth-stabilized coordinate system, and includes the target azimuth angle β0 and the pitch angle ε0; Step 2: Calculate the azimuth angle β and elevation angle ε of the target in the photoelectric coordinate system using coordinate transformation according to the obtained target angle and target distance; Step 3: Establish the time equations for the two paths of the optoelectronic system transitioning from the high-speed search process to the tracking state. The first path is that the optoelectronic system moves forward from the current position, first moves at a constant speed at the search speed, then decelerates to zero, and reaches the target position. The time required is t1. The second path is that the optoelectronic system decelerates from the current position at the search speed to the zero position, then turns around and moves in the opposite direction, first accelerates to the maximum turning speed, then moves at a constant speed, and finally decelerates to zero. The time required is t2: Where V s is the search speed of the optoelectronic system, a t is the acceleration of the photoelectric system, S1 is the angular travel of the photoelectric system from the search speed to zero, S2 is the angular travel of the photoelectric system moving to the target position through the first path, V t is the maximum turning speed of the photoelectric system, S3 is the angular stroke of the photoelectric system in the second path from deceleration to zero position to reverse movement to the target position, S4 is the angular stroke of the photoelectric system from the maximum turning speed to zero, S2-S1+S3=360°; Step 4: Assume that the time t1 required for the photoelectric system to select the first path is equal to the time t2 required for the second path. Use the time equation established in step 3 to calculate the angular travel S2 of the photoelectric system to the target position via the first path: Step 5: Select the optimal path based on the relationship between the difference between the azimuth angle β of the optoelectronic system and the azimuth angle β of the target in the optoelectronic system coordinate system and the angular travel S2 calculated in step 4, so as to minimize the reaction time of the optoelectronic system from the high-speed search process to the tracking state: If β, -β<S2, then choose the first path; If β, -β>S2, then choose the second path; If β, -β = S2, the two paths take the same amount of time and either path can be chosen arbitrarily.

2. The optimal path calculation method for high-speed search and tracking of an optoelectronic system according to claim 1, characterized in that: In step 5, if β, -β<S1, it means that when the optoelectronic system decelerates from the high-speed search state to zero, it has exceeded the target position and needs to turn in the opposite direction. In this case, the second path is selected.

3. The optimal path calculation method for high-speed search and tracking of an optoelectronic system according to claim 1 or 2, characterized in that: Step 2 includes the following sub-steps: Step 2.1, convert the target angle from polar coordinates to rectangular coordinates: Where x, y, and z are the rectangular coordinates of the target in the carrier's stable coordinate system or the earth's stable coordinate system, and R is the target distance; Step 2.2, convert the target rectangular coordinates from the carrier stable coordinate system or the earth stable coordinate system to the photoelectric coordinate system: Where x, y, and z are the rectangular coordinates of the target in the photoelectric coordinate system, ψ is the carrier pointing angle, θ is the roll angle, and φ is the pitch angle. Step 2.3, convert the target rectangular coordinates in the photoelectric coordinate system into polar coordinates:

4. The optimal path calculation method for high-speed search and tracking of an optoelectronic system according to claim 3, characterized in that: The target angle is the coordinate in the stable coordinate system of the carrier, ψ=0.

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