An unmanned ship autonomous navigation performance test system and method

Abstract

The application discloses an unmanned ship autonomous navigation performance test system and method, which is composed of a test field based on a thermal imaging image acquisition module, a mark module with a settable temperature and a shore-based data processing and control visualization platform. First, thermal imaging cameras are arranged at four corners of the test field and spherical markers are arranged on the unmanned ship to be tested. Then, the temperature of the spherical markers is set to be different from the ambient temperature, so that the thermal imaging cameras can clearly shoot the shape. Next, the unmanned ship travels according to a preset test route, and each thermal imaging camera continuously shoots the spherical markers on the unmanned ship during navigation. After that, the change of the actual position of the unmanned ship is solved by using the change of the image coordinates of the spherical markers in the images shot by each thermal imaging camera, and the actual navigation track of the unmanned ship is recorded. Finally, the advantages and disadvantages of the autonomous navigation performance of the unmanned ship are evaluated by analyzing the actual navigation track of the unmanned ship.

Description

Technical Field

[0001] This invention relates to the field of unmanned surface vessel (USV) autonomous navigation performance testing technology, and in particular to a USV autonomous navigation performance testing system and method. Background Technology

[0002] Unmanned surface vessels (USVs) have attracted significant attention both domestically and internationally due to their immense potential in national defense, security and anti-smuggling, patrol and search and rescue, and hydrological data collection. Governments, research institutions, and related enterprises worldwide have invested substantial human and material resources in USV research, while continuously promoting the application of research findings. However, on the one hand, USVs, as intelligent agents, integrate sensing, control, and communication systems; on the other hand, they are primarily used for dangerous missions unsuitable for manned vessels, often operating in harsh environments. Therefore, comprehensive testing and verification of the autonomous navigation performance and safety of USVs are crucial and a prerequisite for ensuring their safe and rapid mission completion. However, as USVs are a relatively new technology, their testing techniques are not yet mature, particularly regarding how to install external measuring instruments for remote, non-contact observation of their navigation performance – a problem that remains to be solved. Summary of the Invention

[0003] To address the problem of remotely observing the navigation performance of unmanned surface vessels (USVs), this invention proposes a system and method for testing the autonomous navigation performance of USVs.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] An unmanned surface vessel (USV) autonomous navigation performance testing system includes:

[0006] The system includes: a test field based on a thermal imaging image acquisition module, a temperature-adjustable marker module, and a shore-based data processing and control visualization platform;

[0007] The test field based on the thermal imaging image acquisition module is set up, and the focal length, field of view, installation height and installation angle of the thermal imaging camera are selected through the module so that the clarity of the acquired image meets the requirements of image coordinate calculation.

[0008] A temperature-adjustable marker module, installed on the unmanned surface vessel under test, consists of a spherical marker and a temperature control module, used to observe, set, and control the surface temperature of the spherical marker;

[0009] The shore-based data processing and control visualization platform collects image information of spherical markers, calculates the actual position of the unmanned surface vessel (USV), evaluates the path tracking and autonomous obstacle avoidance performance of the USV, and visualizes the trajectory error of path tracking.

[0010] A method for testing the autonomous navigation performance of an unmanned surface vessel (USV), comprising:

[0011] Thermal imaging cameras were set up at the four corners of the test field;

[0012] Place spherical markers on the unmanned surface vessel being tested;

[0013] Set the temperature of the spherical marker to be different from the ambient temperature;

[0014] The unmanned surface vessel (USV) travels along the preset test route, and each thermal imaging camera continuously captures images of the spherical marker on the USV during its journey.

[0015] The actual position coordinates of the unmanned surface vessel are determined by using the image coordinates of the spherical marker in the images captured by each thermal imaging camera, and the actual navigation trajectory of the unmanned surface vessel is tracked and acquired by continuous shooting.

[0016] The quality of an unmanned surface vessel's autonomous navigation performance is evaluated by analyzing its actual navigation trajectory.

[0017] Compared with the prior art, one or more embodiments of the present invention may have the following advantages:

[0018] It features the ability to meet 24-hour all-weather testing requirements, long detection range, unaffected by strong light, good real-time image acquisition, and high accuracy. Attached Figure Description

[0019] Figure 1 This is a block diagram of the unmanned surface vessel autonomous navigation performance testing system;

[0020] Figure 2 This is a schematic diagram of the test field layout based on the thermal imaging image acquisition module;

[0021] Figure 3 This is a flowchart for using a thermal imaging camera to determine the actual position coordinates of an unmanned surface vessel. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in further detail below with reference to the embodiments and accompanying drawings.

[0023] like Figure 1 As shown, this is an autonomous navigation performance testing system for unmanned surface vessels, which includes a test field based on a thermal imaging image acquisition module, a temperature-adjustable marker module, and a shore-based data processing and control visualization platform.

[0024] like Figure 2As shown, the test field based on the thermal imaging image acquisition module is a rectangular test water area. Thermal imaging image acquisition modules are set up at the four corners of the test field. The focal length, field of view, installation height and installation angle of the thermal imaging camera are selected according to the size of the test water area to ensure that the unmanned vessel will not leave the field of view of the thermal imaging camera during the test, and that the clarity of the acquired images can meet the requirements of image coordinate calculation.

[0025] The thermal imaging image acquisition module specifically includes a thermal imaging camera, an industrial control computer, and a communication radio. The thermal imaging camera transmits the acquired thermal images of the unmanned surface vessel (USV) directly to the industrial control computer via a network cable. The industrial control computer calculates the image coordinates of the spherical marker on the USV based on the thermal images, adds a timestamp, packages it into a message segment, and transmits it back to the shore-based data processing platform via the communication radio.

[0026] A temperature-adjustable marker module is installed on the unmanned surface vessel (USV) under test. It consists of a spherical marker and a temperature control module. The spherical marker is installed vertically at a high position on the USV for easy observation. The temperature control module is used to set and control the surface temperature of the spherical marker so that the thermal imaging camera can distinguish the shape and position of the marker from the ambient temperature.

[0027] The shore-based data processing and control visualization platform mainly includes: an unmanned surface vessel (USV) navigation position calculation module, an autonomous navigation performance evaluation module, and a 3D visualization module. The USV navigation position calculation module collects image information from a spherical marker on the USV under test using four thermal imaging cameras deployed in the test field, and calculates the USV's actual position based on the acquired images. The autonomous navigation performance evaluation mainly assesses the USV's path tracking and autonomous obstacle avoidance performance based on the data obtained from the USV navigation position calculation module. The evaluation indicators for path tracking are the intersection error and heading angle error between the actual and desired trajectories; the evaluation indicators for autonomous obstacle avoidance are reaction distance, regression distance, and obstacle avoidance time. The 3D visualization module specifically includes: displaying the USV's actual navigation trajectory in real time based on the information from the USV navigation position calculation module, and comparing it with the set desired trajectory to visualize the trajectory error of path tracking.

[0028] This embodiment also provides a method for testing the autonomous navigation performance of unmanned surface vessels, including arranging thermal imaging cameras at the four corners of the test field;

[0029] Place spherical markers on the unmanned surface vessel being tested;

[0030] Set the temperature of the spherical marker to be different from the ambient temperature so that the thermal imaging camera can clearly capture its shape.

[0031] The unmanned surface vessel (USV) travels along the preset test route, and each thermal imaging camera continuously captures images of the spherical marker on the USV during its journey.

[0032] like Figure 3 As shown, the actual position coordinates of the unmanned surface vessel (USV) are determined by using the image coordinates of the spherical marker in the images captured by each thermal imaging camera. Furthermore, the actual navigation trajectory of the USV is tracked and acquired through continuous imaging. The specific method is as follows:

[0033] According to the optical path equation of a thermal imaging camera:

[0034]

[0035]

[0036] In the formula, x and y are the image coordinates of the marker in the image captured by the thermal imaging camera; X, Y, and Z are the actual position coordinates of the marker in the test field; Δx and Δy are the nonlinear distortions of the thermal imaging camera objective lens; l1, l2, ..., l 11 These are the coefficients of the optical path equation; they can be taken as...

[0037] Δx=k1(x-x0)r 2 (3)

[0038] Δy=k1(y-y0)r 2 (4)

[0039]

[0040] Where k1 is the distortion scaling factor, and x0 and y0 are the coordinates of the principal point in the image, which can be obtained by the following formula:

[0041]

[0042]

[0043] Multiple markers with known actual coordinates were placed at different locations in the test field. Each thermal imaging camera photographed the markers with known actual coordinates and obtained their image coordinates. The image coordinates and actual coordinates of each marker were substituted into equations (1)-(7) to solve for l1, l2, ..., l 11 The specific values ​​of the 12 coefficients, including k1, are used to complete the optical path calibration of the thermal imaging camera. After calibration, the one-to-one correspondence between the image coordinates x and y and the actual position coordinates X, Y, and Z can be determined by equations (1) to (7).

[0044] Each thermal imaging camera takes pictures of the markers on the unmanned surface vessel (USV) and obtains their image coordinates. Substituting the image coordinates into the calibrated equations (1)-(7), the actual coordinates of the markers can be calculated. The actual navigation trajectory of the USV is obtained through continuous shooting.

[0045] Ultimately, the autonomous navigation performance of the unmanned surface vessel (USV) is evaluated by analyzing its actual navigation trajectory.

[0046] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and variations in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection for this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A system for testing the autonomous navigation performance of unmanned surface vessels, characterized in that, The system includes: a test field based on a thermal imaging image acquisition module, a temperature-adjustable marker module, and a shore-based data processing and control visualization platform; The test field based on the thermal imaging image acquisition module is set up, and the focal length, field of view, installation height and installation angle of the thermal imaging camera are selected through the module so that the clarity of the acquired image meets the requirements of image coordinate calculation. A temperature-adjustable marker module, installed on the unmanned surface vessel under test, consists of a spherical marker and a temperature control module, used to observe, set, and control the surface temperature of the spherical marker; The shore-based data processing and control visualization platform collects image information of spherical markers, calculates the actual position of the unmanned surface vessel (USV), evaluates the path tracking and autonomous obstacle avoidance performance of the USV, and visualizes the trajectory error of path tracking. The test field based on the thermal imaging image acquisition module is a rectangular test water area, with thermal imaging image acquisition modules set up at the four corners of the test field; the focal length, field of view, installation height, and installation angle of the thermal imaging camera are selected according to the size of the test water area. The thermal imaging image acquisition module specifically includes: a thermal imaging camera, an industrial control computer, and a communication radio. The thermal imaging camera transmits the acquired thermal imaging images of the unmanned surface vessel directly to the industrial control computer via a network cable. The industrial control computer calculates the image coordinates of the spherical marker on the unmanned surface vessel based on the thermal imaging images, adds a timestamp, packages it into a message segment, and transmits it back to the shore-based data processing platform via the communication radio. The temperature-adjustable marker module is installed on the unmanned surface vessel under test and consists of a spherical marker and a temperature control module. The spherical marker is installed vertically at a high position on the unmanned surface vessel for easy observation. The temperature control module is used to set and control the surface temperature of the spherical marker so that the thermal imaging camera can distinguish the shape and position of the marker from the ambient temperature. The actual position coordinates of the unmanned surface vessel (USV) are determined by using the image coordinates of a spherical marker in the images captured by various thermal imaging cameras. Furthermore, the actual navigation trajectory of the USV is tracked and acquired through continuous image capture. Specifically, this includes: According to the optical path equation of a thermal imaging camera: In the formula, x and y are the image coordinates of the marker in the image captured by the thermal imaging camera; X, Y, and Z are the actual position coordinates of the marker in the test field; Δx and Δy are the nonlinear distortions of the thermal imaging camera objective lens; l1, l2, ..., l 11 These are the coefficients of the optical path equation; they can be taken as... Δx=k1(x-x0)r 2 (3) Δy=k1(y-y0)r 2 (4) Where k1 is the distortion scaling factor, and x0 and y0 are the coordinates of the principal point in the image, which can be obtained by the following formula: Multiple markers with known actual coordinates were placed at different locations in the test field. Each thermal imaging camera photographed the markers with known actual coordinates and obtained their image coordinates. The image coordinates and actual coordinates of each marker were substituted into equations (1)-(7) to solve for l1, l2, ..., l 11 The specific values ​​of the 12 coefficients k1 are used to complete the optical path calibration of the thermal imaging camera; after calibration, the one-to-one correspondence between the image coordinates x and y and the actual position coordinates X, Y, and Z can be determined by equations (1) to (7); Each thermal imaging camera takes pictures of the markers on the unmanned surface vessel and obtains their image coordinates; by substituting the image coordinates into the calibrated equations (1)-(7), the actual coordinates of the markers can be solved; the actual navigation trajectory of the unmanned surface vessel is obtained by continuous shooting. The shore-based data processing and control visualization platform includes an unmanned surface vessel navigation position calculation module, an autonomous navigation performance evaluation module, and a 3D visualization module. The unmanned surface vessel (USV) navigation position calculation module collects image information of the spherical marker of the USV under test through four thermal imaging cameras set up in the test field, and calculates the actual position of the USV based on the collected images. The autonomous navigation performance evaluation module evaluates the path tracking and autonomous obstacle avoidance performance of the unmanned surface vessel (USV) based on the data obtained from the USV's navigation position calculation module. The evaluation indicators for path tracking are the crossover error between the actual trajectory and the desired trajectory and the heading angle error. The evaluation indicators for autonomous obstacle avoidance are reaction distance, return distance, and obstacle avoidance time. The 3D visualization module, based on information from the unmanned surface vessel's (USV) navigation position calculation module, displays the USV's actual navigation trajectory in real time and compares it with the set expected trajectory to visualize the trajectory error of path tracking.

2. A method for testing the autonomous navigation performance of an unmanned surface vessel, characterized in that, include: Thermal imaging cameras were set up at the four corners of the test field; Place spherical markers on the unmanned surface vessel being tested; Set the temperature of the spherical marker to be different from the ambient temperature; The unmanned surface vessel (USV) travels along the preset test route, and each thermal imaging camera continuously captures images of the spherical marker on the USV during its journey. The actual position coordinates of the unmanned surface vessel are determined by using the image coordinates of the spherical marker in the images captured by each thermal imaging camera, and the actual navigation trajectory of the unmanned surface vessel is tracked and acquired by continuous shooting. The quality of autonomous navigation performance of unmanned surface vessels (USVs) is evaluated by analyzing their actual navigation trajectories. The actual position coordinates of the unmanned surface vessel (USV) are determined by using the image coordinates of a spherical marker in the images captured by various thermal imaging cameras. Furthermore, the actual navigation trajectory of the USV is tracked and acquired through continuous image capture. Specifically, this includes: According to the optical path equation of a thermal imaging camera: In the formula, x and y are the image coordinates of the marker in the image captured by the thermal imaging camera; X, Y, and Z are the actual position coordinates of the marker in the test field; Δx and Δy are the nonlinear distortions of the thermal imaging camera objective lens; l1, l2, ..., l 11 These are the coefficients of the optical path equation; they can be taken as... Δx=k1(x-x0)r 2 (3) Δy=k1(y-y0)r 2 (4) Where k1 is the distortion scaling factor, and x0 and y0 are the coordinates of the principal point in the image, which can be obtained by the following formula: Multiple markers with known actual coordinates were placed at different locations in the test field. Each thermal imaging camera photographed the markers with known actual coordinates and obtained their image coordinates. The image coordinates and actual coordinates of each marker were substituted into equations (1)-(7) to solve for l1, l2, ..., l 11 The specific values ​​of the 12 coefficients k1 are used to complete the optical path calibration of the thermal imaging camera; after calibration, the one-to-one correspondence between the image coordinates x and y and the actual position coordinates X, Y, and Z can be determined by equations (1) to (7); Each thermal imaging camera takes pictures of the markers on the unmanned surface vessel and obtains their image coordinates; by substituting the image coordinates into the calibrated equations (1)-(7), the actual coordinates of the markers can be solved; the actual navigation trajectory of the unmanned surface vessel is obtained by continuous shooting.

Images