An improved unmanned surface vehicle target tracking method

Abstract

This invention discloses an improved unmanned surface vessel (USV) target tracking method: Step 1, acquire target USV position and heading angle data to obtain target USV sampling data; Step 2, based on the target USV sampling data, obtain heading angle change data at adjacent sampling times; Step 3, smooth the heading angle change data to obtain preprocessed data; Step 4, based on the preprocessed data and combined with the designed offset law, calculate the offset angle α; Step 5, calculate the absolute azimuth angle of the line segment connecting the USV and the target USV according to the target USV's heading angle and offset angle α; Step 6, based on the absolute azimuth angle and the target USV's position coordinate information (x... target ,y target ) Calculate the tracking point (x) under the relative time-varying point tracking strategy tracking ,y tracking The tracking point coordinates are obtained. This invention overcomes the problem of poor tracking performance when the target vessel turns, which exists in the tracking method that uses the center of the fan-ring domain as the tracking point. It also improves the target tracking effect and control stability, while reducing the energy consumption of the unmanned surface vessel.

Description

Technical Field

[0001] This invention relates to the field of target tracking, specifically to an improved method for tracking unmanned surface vessels (USVs). Background Technology

[0002] Unmanned surface vessel (USV) target tracking capabilities have significant applications in both military and civilian sectors. An effective tracking strategy is a prerequisite for USVs to successfully complete target tracking tasks. Common USV tracking scenarios include... Figure 1 As shown, firstly, taking the target vessel as the center, and using the maximum tracking distance... and minimum tracking distance To prevent the unmanned surface vessel from losing track of the target due to a large turning radius caused by drastic changes in the bow angle during tracking, a symmetrical deflection angle is set behind the target vessel, centered on the target's bow angle. This limits the tracking area of ​​the unmanned surface vessel to an opening angle of [missing information]. Outer diameter is Inner diameter is Within the fan-shaped annular domain.

[0003] The commonly used tracking method currently is to use the center position of the fan-shaped annular region as the tracking point, that is... Figure 1 Point A in the diagram. The coordinates of point A are calculated using the following formula:

[0004]

[0005] In the formula, Indicates the heading angle of the target vessel. Indicates the location of the target vessel. Indicates the location of the tracking point.

[0006] The drawback of this tracking method is that when the target vessel makes a large maneuver, the heading angle changes drastically, causing a significant shift in the tracking point. Furthermore, the initial heading change direction of the unmanned surface vessel is opposite to that of the target vessel. Figure 2 As shown, when the target vessel moves from point P1 to point P2, its heading changes counterclockwise. The optimal tracking point shifts clockwise from point A1 to point A2. To ensure tracking the target position, the UAV's heading will initially shift clockwise. However, to maintain a roughly aligned heading with the target vessel, the UAV's heading angle will then change counterclockwise. During this process, the UAV's heading undergoes a cycle of "first reversing the direction of the target vessel's heading change, then returning to the correct direction and finally tracking the target vessel's heading." This method increases the magnitude of the UAV's heading change, raising the risk of tracking mission failure. Summary of the Invention

[0007] This invention was made to solve the above-mentioned problems, and its purpose is to provide an improved unmanned surface vessel target tracking method.

[0008] This invention provides an improved unmanned surface vessel (USV) target tracking method, characterized by the following steps: Step 1, acquiring target USV position and heading angle data to obtain target USV sampling data; Step 2, based on the target USV sampling data, obtaining heading angle change data of the target USV at adjacent sampling times. Step 3: Use a first-order lag filter method to process the heading angle variation data. Step 4: Based on the preprocessed data and the designed offset rate, calculate the offset angle using the smoothing process to obtain preprocessed data. Step 5, based on the target vessel's bow angle and offset angle The absolute azimuth angle of the line segment connecting the unmanned surface vessel and the target vessel was calculated. Step 6, based on absolute azimuth angle Based on the target vessel's position coordinates Calculate the tracking point under the relative time-varying point tracking strategy The coordinates of the tracking point are obtained.

[0009] The improved unmanned surface vessel target tracking method provided by this invention may also have the following feature: wherein, in step 3, the calculation formula for smoothing is: In the formula, It is a weighting factor. This represents the filtering result from the previous time step. This represents the sampled data at the current moment. This indicates the filtering result at the current moment.

[0010] The improved unmanned surface vessel target tracking method provided by this invention may also have the following feature: wherein, in step 4, the offset angle... The calculation formula is: In the formula, To adjust the parameters, .

[0011] The improved unmanned surface vessel target tracking method provided by this invention may also have the following feature: wherein, in step 5, the absolute azimuth angle The calculation formula is:

[0012] The improved unmanned surface vessel target tracking method provided by this invention may also have the following feature: wherein, in step 6, the tracking point The calculation formula is:

[0013] .

[0014] The present invention provides an electronic device having the features of including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in the present invention.

[0015] The present invention provides an unmanned surface vessel that is equipped with electronic devices.

[0016] The present invention provides an electronic device having the features of including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in the present invention.

[0017] The present invention provides a storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the present invention.

[0018] The present invention provides a computer program product comprising a computer program having the feature that the computer program is executed by a processor to implement the method described in the present invention.

[0019] The role and effect of invention

[0020] The improved unmanned surface vessel (USV) target tracking method according to the present invention includes the following steps: Step 1, acquiring target vessel position and heading angle data to obtain target vessel sampling data; Step 2, based on the target vessel sampling data, obtaining heading angle change data of the target vessel at adjacent sampling times. Step 3: Use a first-order lag filter method to process the heading angle variation data. Step 4: Based on the preprocessed data and the designed offset rate, calculate the offset angle using the smoothing process to obtain preprocessed data. Step 5, based on the target vessel's bow angle and offset angle The absolute azimuth angle of the line segment connecting the unmanned surface vessel and the target vessel was calculated. Step 6, based on absolute azimuth angle Based on the target vessel's position coordinates Calculate the tracking point under the relative time-varying point tracking strategy The tracking point coordinates are obtained. Therefore, this invention shifts the target tracking point of the unmanned surface vessel (USV) from the center of the fan-ring domain relative to the bow direction extension line of the target vessel at a certain angle according to a certain rule. This overcomes the problem of poor tracking effect when the target vessel turns, which exists in the tracking method with the center of the fan-ring domain as the tracking point. It also improves the target tracking effect and control stability, while reducing the energy consumption of the USV. Attached Figure Description

[0021] Figure 1 This is a scene diagram of target tracking in the background technology;

[0022] Figure 2 This is a schematic diagram illustrating the drawbacks of the methods described in the background technology.

[0023] Figure 3 These are tracking reference trajectory diagrams generated from embodiments and comparative examples of the present invention. Detailed Implementation

[0024] To make the technical means, creative features, objectives and effects of the present invention easy to understand, the following embodiments, in conjunction with the accompanying drawings, specifically illustrate an improved unmanned surface vessel target tracking method of the present invention.

[0025] To overcome the shortcomings of existing methods, this embodiment proposes an improved unmanned surface vessel (USV) target tracking method. In this embodiment, the tracking point at the center of the fan-ring domain in the original method in the background art is offset to both sides by a certain angle relative to the extension line of the bow direction of the target vessel, in accordance with a certain rule. This makes full use of the constrained space of the fan-ring domain, which is conducive to the tracking reference trajectory being close to the actual navigation trajectory of the target vessel.

[0026] Using the method in the background art as a comparative example, in order to ensure the comparison effect, the unmanned surface vessel trajectory tracking controllers in the embodiments and comparative examples all adopt the same model prediction controller with the same parameter settings.

[0027] In this embodiment, the maximum speed of the target vessel is set to 2 m / s, and the target vessel's speed and heading angle change according to a specified pattern during the tracking process. The initial position of the target vessel is the origin (0,0) m, and the maximum distance in the tracking area is... minimum distance The desired distance is 10m, and the deflection angle of the fan-shaped area is... The initial position of the unmanned surface vessel is (-9.4, -3.4) m, and the initial heading angle is... The simulation time is 120 seconds.

[0028] The mathematical model of the unmanned surface vessel adopts a three-degree-of-freedom model, and the model parameters are as follows: , , , , , The ranges for longitudinal thrust and yaw moment are as follows:

[0029]

[0030] The parameters for the unmanned surface vessel (USV) model predictive controller used for target tracking are set as follows: Control Domain Prediction domain Output weights Control Quantity Weight .

[0031] The specific implementation steps are as follows: Step 1, obtain the target vessel's position and heading angle data to obtain the target vessel sampling data.

[0032] Step 2: Based on the target vessel's sampled data, obtain the bow angle change data of the target vessel at adjacent sampling times. .

[0033] Step 3: Apply a first-order lag filter to the heading angle variation data. Smoothing is performed to obtain preprocessed data.

[0034] Step 4: Based on the preprocessed data and the designed offset rate, calculate the offset angle. .

[0035] Step 5, based on the target boat's bow angle and offset angle The absolute azimuth angle of the line segment connecting the unmanned surface vessel and the target vessel was calculated. .

[0036] Step 6, based on absolute azimuth angle Based on the target vessel's position coordinates Calculate the tracking point under the relative time-varying point tracking strategy The coordinates of the tracking point are obtained.

[0037] Finally, the coordinates of the tracking point are used as reference inputs to the unmanned surface vessel (USV) target tracking controller to generate a reference trajectory, and a model prediction controller is used to track the generated reference trajectory.

[0038] Figure 3 These are tracking reference trajectory diagrams generated under two tracking methods in the embodiments and comparative examples of the present invention.

[0039] Table 1 shows the changes in the relative distance between the unmanned surface vessel (USV) and the target vessel during the tracking process under the two tracking methods.

[0040] Table 1

[0041]

[0042] Table 2 shows the energy consumption, reference trajectory length, and actual tracking trajectory length of the unmanned surface vessel under the two tracking methods.

[0043] Table 2

[0044]

[0045] Table 3 compares the longitudinal thrust results during the tracking process of the unmanned surface vessel under the two tracking methods.

[0046] Table 3

[0047]

[0048] Table 4 compares the bow torque results during the tracking process of the unmanned surface vessel under the two tracking methods.

[0049] Table 4

[0050]

[0051] The comparison results above show that the unmanned surface vessel target tracking method proposed in this embodiment has advantages over the comparative method in terms of trajectory generation, tracking effect, energy loss and control stability.

[0052] The role and effect of the embodiments

[0053] The improved unmanned surface vessel (USV) target tracking method according to this embodiment includes the following steps: Step 1, acquiring the target USV's position and heading angle data to obtain target USV sampling data; Step 2, based on the target USV sampling data, obtaining the heading angle change data of the target USV at adjacent sampling times. Step 3: Use a first-order lag filter method to process the heading angle variation data. Step 4: Based on the preprocessed data and the designed offset rate, calculate the offset angle using the smoothing process to obtain preprocessed data. Step 5, based on the target vessel's bow angle and offset angle The absolute azimuth angle of the line segment connecting the unmanned surface vessel and the target vessel was calculated. Step 6, based on absolute azimuth angle Based on the target vessel's position coordinates Calculate the tracking point under the relative time-varying point tracking strategy The coordinates of the tracking point are obtained.

[0054] Therefore, in this embodiment, the target tracking point of the unmanned surface vessel is shifted to both sides by a certain angle from the center of the fan ring domain relative to the bow direction of the target vessel, in accordance with a certain rule. This overcomes the problem of poor tracking effect when the target vessel turns, which exists in the tracking method with the center of the fan ring domain as the tracking point. It also improves the target tracking effect and control stability, while reducing the energy consumption of the unmanned surface vessel.

Claims

1. An improved target tracking method for unmanned surface vessels, characterized in that, Includes the following steps: Step 1: Obtain the target vessel's position and heading angle data to obtain target vessel sampling data; Step 2: Based on the target vessel's sampled data, obtain the bow angle change data of the target vessel at adjacent sampling times. ; Step 3: Apply a first-order hysteresis filtering method to the heading angle variation data. Smoothing is performed to obtain preprocessed data; Step 4: Based on the preprocessed data and the designed offset rate, calculate the offset angle. ; Step 5, based on the target boat's bow angle and the offset angle The absolute azimuth angle of the line segment connecting the unmanned surface vessel and the target vessel was calculated. ; Step 6, based on the absolute azimuth angle Based on the target vessel's position coordinates Calculate the tracking point under the relative time-varying point tracking strategy The coordinates of the tracking point are obtained. In step 3, the calculation formula for the smoothing process is as follows: In the formula, It is a weighting factor. This represents the filtering result from the previous time step. This represents the sampled data at the current moment. This represents the filtering result at the current moment. In step 4, the offset angle The calculation formula is: In the formula, To adjust the parameters, 。 2. The improved unmanned surface vessel target tracking method according to claim 1, characterized in that: in, In step 5, the absolute azimuth angle The calculation formula is: 。 3. The improved unmanned surface vessel target tracking method according to claim 1, characterized in that: in, In step 6, the tracking point The calculation formula is: 。 4. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor executes the computer program to implement the method as described in any one of claims 1-3.

5. An unmanned surface vessel, characterized in that, The device is provided with the electronic equipment as described in claim 4.

6. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1 to 3.

7. A computer program product, comprising a computer program, characterized in that, The computer program is executed by a processor to implement the method according to any one of claims 1-3.

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