An unmanned ship offshore reef obstacle avoidance device and method

Abstract

The application relates to the technical field of ship body protection devices, in particular to an unmanned ship offshore reef obstacle avoidance device, which comprises a sonar arranged on the lower side of a ship body and an electric control unit arranged in the ship body, and the electric control unit is used for processing echo signals received by the sonar. When the unmanned ship is affected by wind and waves during task execution at sea, the inertial force of the sliding block is utilized to make the sliding block and the ship body relatively displace, the angle between the connecting rod and the bottom surface of the ship body is adjusted by the sliding block in combination with the pose adjusting assembly, the distance between the sonar and the sea level is adjusted, the pose change of the sonar following the ship body is avoided, the beam emission angle and the beam receiving angle of the sonar are prevented from deviating, the horizontal detection range of the sonar is ensured, the change of the form and intensity of the echo signals caused by the height change of the sonar and the sea level is avoided, and the detection effect of the sonar on small targets is ensured.

Description

Technical Field

[0001] This invention relates to the field of ship protection devices, specifically to an unmanned vessel obstacle avoidance device and method for marine reefs. Background Technology

[0002] Unmanned surface vessels (USVs) often need to enter unknown or complex shallow waters during marine exploration and scientific research missions. During these missions, they are prone to encountering visible reefs, hidden reefs, shoals, marine life, and other obstacles. Therefore, these USVs are typically equipped with automatic obstacle avoidance systems. These systems help USVs detect and avoid these obstacles to ensure the mission's success and protect the vessel and scientific instruments. Common obstacle detection devices for ships include electromagnetic radar, lidar, and sonar. However, in underwater environments, the energy of electromagnetic and light waves is severely attenuated by seawater. Therefore, electromagnetic radar and lidar cannot perform long-distance, high-precision measurements underwater, potentially causing USVs to fail to detect reefs in time, leading to grounding and damage. In contrast, sound waves experience less energy attenuation when propagating in water, allowing them to travel longer distances and possessing better penetration capabilities. Therefore, USVs typically use sonar equipment as their underwater obstacle avoidance device.

[0003] Sonar can be installed either externally or internally on a ship. A drawback of both methods is that unmanned surface vessels (USVs) are smaller and lighter than larger vessels, making them less resistant to wind and waves. This means that when USVs are operating, they are prone to significant attitude changes due to wave action, and the sonar equipment will follow suit. This can lead to the following problems: First, the sonar's beam emission and reception angles may shift, resulting in errors in the calculation of detection and target distances. For example, the ship's pitch may reduce the horizontal detection range of the sonar or cause the detected target distance to deviate from the actual distance. Second, when the sonar equipment moves or vibrates with the USV, the echo signal received by the sonar system may become blurred or distorted, reducing the accuracy of target measurement and increasing the measurement error of the sonar system. Third, changes in the sonar equipment's attitude alter the shape and intensity of the echo signal, negatively impacting the sonar system's target detection and tracking capabilities. This is especially true for small targets, where attitude changes can easily lead to the masking or loss of the target's echo signal.

[0004] To address the aforementioned problems, existing technologies have proposed several solutions. For example, patent application number CN202123179083.X provides a small hull stabilizer that uses a gyroscope mounted on the hull's bottom plate. The gyroscope monitors the hull's specific state and transmits the signal to a controller. After analyzing and processing the signal, the controller controls the movement direction and distance of the counterweight through an active drive mechanism and a driven drive mechanism, thereby achieving automatic adjustment and enabling the small hull to sail stably. Another example is patent application number CN202222818180.7, which provides a ship balance cabin and a ship that uses gyroscope balancing technology to control the ship's attitude and achieve hull balance. However, the above solutions can only reduce the hull's sway amplitude and therefore cannot suppress the influence of wind and waves on the attitude of sonar equipment. Summary of the Invention

[0005] The purpose of this invention is to provide an obstacle avoidance device and method for unmanned surface vessels (USVs) on the sea, in order to solve the problem that when USVs are tossed about by wind and waves, the obstacle avoidance device changes position and attitude with the USV, which causes errors in the detection distance of the obstacle avoidance device or loss of small targets, thus making it impossible for the USV to accurately detect the reefs in its path.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an unmanned surface vessel (USV) obstacle avoidance device for reefs at sea, comprising a sonar mounted on the underside of the hull and an electronic control unit mounted inside the hull, wherein the electronic control unit is used to process the echo signals received by the sonar; when the USV is performing a mission at sea, it is prone to at least one of the following movements: roll, pitch, and heave, due to the action of wind and waves on the sea surface. If the sonar is fixedly installed to the hull, all three movements will affect the sonar's attitude; therefore, the USV obstacle avoidance device for reefs at sea further includes a slider and an attitude adjustment component, wherein the slider is mounted inside the hull. The device is connected to a slider that is movable in both horizontal and vertical directions. The slider is equipped with an attitude adjustment component, and a connecting rod is connected to the lower end of the slider. The lower end of the connecting rod is fixedly connected to the sonar. When the hull is subjected to wind and waves, the slider is subjected to inertial force and undergoes relative displacement with the attitude adjustment component. When the slider loses the inertial force, the attitude adjustment component drives the slider to reset. When the slider moves, it drives the connecting rod to rotate around the attitude adjustment component, keeping the connecting rod perpendicular to the sea level and maintaining the vertical distance between the sonar and the sea level.

[0007] Therefore, when the unmanned surface vessel (USV) is subjected to wind and waves, its posture in the direction of the force will change accordingly. Since the slider is elastically connected to the hull, the slider is subjected to inertial force. Therefore, the direction of movement of the slider is opposite to the direction of the posture change of the hull. At the same time as the slider and the hull undergo relative displacement, the slider drives the posture adjustment component to adjust the angle between the connecting rod and the bottom surface of the hull, and adjusts the distance between the sonar and the sea surface. This prevents the sonar from changing posture with the hull, thereby ensuring the accuracy of the sonar detection range and the detection effect of the sonar on small targets.

[0008] Furthermore, when the hull is subjected to waves, the slider maintains its initial direction of motion under the action of inertial force, and the direction of motion of the slider is opposite to the direction of the hull's posture change. At this time, the hull and the slider undergo relative displacement, thereby shifting the center of gravity of the hull along the direction of the slider's motion. This shift in the center of gravity of the hull in this direction generates a flexural force acting on the hull, thereby counteracting the force of the wind and waves in this direction and reducing the swaying amplitude of the hull when subjected to wind and waves.

[0009] Optionally, the posture adjustment component can be any one of a servo motor group, a robotic arm or a pneumatic joint, or a hydraulic arm. All four posture adjustment components can adjust the angle between the connecting rod and the bottom surface of the hull. However, the equipment investment cost of the servo motor group and the robotic arm is relatively high, which will increase the production and maintenance costs of the unmanned vessel. The power consumption of the pneumatic joint and the hydraulic arm is relatively high, which is not conducive to the endurance of the unmanned vessel. Therefore, none of the above four solutions are preferred solutions of the present invention.

[0010] Preferably, the posture adjustment assembly includes a mounting base, a horizontal adjustment spring, a base plate, a vertical adjustment spring, a rocker arm, a swing arm, and a second ball joint. The mounting base is fixedly connected to the hull, and the base plate is located below the mounting base, with the two connected by a vertical adjustment spring. The number of vertical adjustment springs is at least three. A horizontal adjustment spring is fixedly installed on the inner wall of the mounting base, with at least three horizontal adjustment springs. Both the vertical and horizontal adjustment springs are evenly distributed around the central circumference of the mounting base. The slider is disposed inside the mounting base, and the ends of multiple horizontal adjustment springs near the center of the mounting base are fixedly connected to the slider. The geometric center of the slider coincides with its center of gravity. A rocker arm is ball-jointed to the center of the lower end face of the slider. The lower end of the rocker arm is threaded to a connecting rod, and a first ball joint is provided in the middle section of the rocker arm. A swing arm is hinged to the first ball joint, and both ends of the swing arm are ball-head structures. A second ball joint is hinged to the end of the swing arm away from the rocker arm, and the second ball joint is fixedly connected to the hull.

[0011] It should be understood that in the above preferred embodiment, when the hull rolls due to the action of waves, the slider is subjected to inertial force, causing horizontal and vertical displacement within the mounting base. Simultaneously, it compresses the horizontal and vertical adjusting springs located on one side of the direction of movement. The upper end of the rocker arm moves along with the slider. Since the middle of the rocker arm is hinged to the swing arm via a first ball joint, and the swing arm is fixedly connected to the hull via a second ball joint, a lever point is formed at the first ball joint. At this time, the direction of movement of the lower end of the rocker arm is opposite to the direction of movement of the slider, and the sonar follows the movement of the lower end of the rocker arm; thus, the hull... When the ship rolls due to sea waves, the angle between the bottom of the hull and the sea level changes. The connecting rod, following the slider, swings around the No. 1 ball joint as a fulcrum, thus keeping the axis of the connecting rod perpendicular to the sea level. Simultaneously, the height distance between the connecting rod and the sea level remains constant, ensuring that the sonar's detection direction does not shift with the ship's roll. This avoids deviations in the sonar's beam emission and reception angles, ensuring the sonar's horizontal detection range. Furthermore, it prevents changes in the shape and intensity of the echo signal caused by changes in the sonar's height relative to the sea level, guaranteeing the sonar's detection effectiveness against small targets.

[0012] It should also be understood that when the hull is pitched and swayed by the waves, the slider is subjected to inertial force, and the slider undergoes vertical displacement within the mounting base. At the same time, it compresses or stretches the vertical adjustment spring, and the sonar follows the relative displacement between the slider and the hull. Thus, the height distance between the connecting rod and the sea level remains unchanged, avoiding changes in the shape and intensity of the echo signal caused by changes in the height of the sonar relative to the sea level, and ensuring the sonar's detection effect on small targets.

[0013] Preferably, a linear actuator is fixedly installed at the front end of the fixed base. The linear actuator includes a drive unit and an execution unit. The drive unit is fixedly connected to the mounting base, and the drive unit and the execution unit are slidably connected coaxially. The end of the execution unit away from the drive unit is elastically connected to the outer wall of the slider. When the slider is in its initial position, the axis of the execution unit passes through the center of the slider. The drive unit is electrically connected to the electronic control unit. Thus, during the movement of the unmanned vessel, the electronic control unit detects the speed of the vessel and controls the distance between the execution unit and the slider according to the speed of the vessel to change the initial position of the slider. This compensates for the angle change between the connecting rod and the sea level of the vessel at different operating speeds, ensuring that the axis of the connecting rod remains perpendicular to the sea level, avoiding the deviation of the sonar beam transmission angle and beam reception angle, and ensuring the horizontal detection range of the sonar.

[0014] Preferably, the base plate is further provided with at least 4 ball bearings, the lower end face of the slider is in rolling connection with the ball bearings, and when the slider is displaced by inertial force, the vertical projection plane of the slider contains at least 4 ball bearings; thereby transforming the sliding friction between the slider and the base plate into the rolling friction between the slider and the ball bearings, improving the slider's response to horizontal inertial force, thus ensuring the slider's displacement effect in the horizontal direction, and thus ensuring the horizontal detection range of the sonar.

[0015] Furthermore, when the hull is subjected to waves and sways downwards, the slider is prone to detach from the base plate, causing the slider to impact the ball bearings. Therefore, the slider and the base plate are magnetically connected, and the ball bearings are made of non-magnetic material. This prevents the slider from detaching from the base plate, ensuring the smoothness of the ball bearings during rolling and preventing the impact sound of the slider and ball bearings from affecting the sonar signal, thereby ensuring the detection accuracy of the sonar and the detection effect on small targets.

[0016] Preferably, the mounting base is located at 1 / 3 to 1 / 2 of the length of the hull, and fins are rotatably connected to both sides of the sonar. The sonar is equipped with a geared motor that drives the fins on both sides to rotate. The rotation axis of the fins intersects with and is perpendicular to the rotation axis of the rocker arm. The geared motor is electrically connected to the electronic control unit.

[0017] It is easy to understand that in the above preferred embodiment, when the hull undergoes pitching and heaving motions due to the action of waves, the fins enhance the vertical drag of the sonar in seawater, further preventing changes in the shape and intensity of the echo signal caused by changes in the height of the sonar above the sea level, thus ensuring the sonar's detection effect on small targets. Simultaneously, the mounting base is located at 1 / 3 to 1 / 2 of the hull's length, reducing the impact of propulsion noise from the stern on the sonar signal. Furthermore, during the operation of the unmanned surface vessel, the electronic control unit adjusts the sonar signal according to the hull's movement. The angle between the side fins and the sea level is adjusted by the speed of the ship. The forward thrust of the hull presses down on the front of the hull, thereby reducing the hull's sway amplitude during pitching. This further prevents the sonar beam transmission and reception angles from shifting, thus ensuring the horizontal detection range of the sonar. Moreover, pressing down on the front of the hull reduces the windward area of ​​the front of the hull, thereby reducing the intensity of the waves at the front of the hull. This reduces the interference of wave noise on the sonar signal, thus ensuring the sonar's detection accuracy for small targets.

[0018] Preferably, the vertical projection surface of the connecting rod is elliptical, with the major axis of the ellipse pointing directly forward of the hull. The center of gravity of the connecting rod coincides with the rotation axis of the rocker arm. This reduces the resistance between the connecting rod and the seawater when the hull is moving. At the same time, the seawater, guided by the surface of the connecting rod, reduces turbulence behind the connecting rod, thereby reducing the vibration of the connecting rod during hull movement and thus reducing the impact of vibration and vibration noise on the sonar signal. Furthermore, when the hull sways due to wind and waves, the elliptical cross-section of the connecting rod increases the lateral resistance between the connecting rod and the seawater, thereby reducing the lateral sway amplitude of the hull and further reducing the impact of hull sway on the sonar attitude. This further prevents the sonar beam emission angle and beam reception angle from shifting, ensuring the horizontal detection range and detection accuracy of the sonar.

[0019] A method for using an unmanned surface vessel (USV) obstacle avoidance device for reefs at sea includes the following steps: S1: The electronic control unit controls the movement of the hull, connects the power supply lines of the linear actuator and the geared motor, and simultaneously activates the sonar; S2: The electronic control unit adjusts the distance between the actuator and the slider according to the real-time operating speed of the hull, and at the same time adjusts the angle between the fin and the sea surface; S3: The sonar acquires echo signals and transmits the signal data to the electronic control unit. The electronic control unit analyzes and processes the received signal data and constructs an environmental topographic map including the location and geometric information of reefs, obstacles, and organisms. S4: The electronic control unit uses algorithms to detect and identify potential obstacles, and determines whether underwater reefs, obstacles, or organisms are on the unmanned vessel's path or pose a threat to the hull. Based on the environmental map and obstacle detection results, the electronic control unit performs path planning and obstacle avoidance strategy calculations, including determining a safe path, avoiding collisions, and adjusting the sailing speed. Through algorithms and decision-making logic, a safe and feasible sailing path is generated. S5: The electronic control unit adjusts the hull's direction of travel and speed according to path planning and obstacle avoidance strategies, so that the hull avoids reefs and other obstacles during navigation. S6: The sonar continues to monitor the surrounding underwater environment and transmits the acquired echo signals to the electronic control unit. If new obstacles or targets appear during navigation, the electronic control unit updates the environmental map and adjusts the path planning and obstacle avoidance strategy accordingly to maintain the safety of the unmanned vessel. S7: After the detection mission is completed, the electronic control unit controls the hull to stop running and cuts off the power supply lines of the linear actuator and geared motor, while shutting down the sonar.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention, by setting up a slider and an attitude adjustment component, utilizes the inertial force of the slider to cause relative displacement between the slider and the hull when the unmanned surface vessel (USV) is subjected to wind and waves during its mission. Furthermore, the slider, in conjunction with the attitude adjustment component, adjusts the angle between the connecting rod and the bottom of the hull, and also adjusts the distance between the sonar and the sea surface. This prevents the sonar from changing its attitude along with the hull, thereby avoiding deviations in the sonar's beam emission and reception angles, ensuring the sonar's horizontal detection range. Simultaneously, it avoids changes in the shape and intensity of the echo signal caused by changes in the sonar's height relative to the sea surface, ensuring the sonar's detection effectiveness against small targets.

[0021] 2. By installing fins on both sides of the sonar, the present invention enhances the vertical resistance of the sonar in seawater when the hull is subjected to pitching and heaving motions by the waves. This improves the sonar's height adjustment effect by the attitude adjustment component and further avoids changes in the shape and intensity of the echo signal caused by changes in the height of the sonar above the sea level, thus ensuring the sonar's detection effect on small targets.

[0022] 3. By setting ball bearings on the base plate, the sliding friction between the slider and the base plate is transformed into rolling friction between the slider and the ball bearings. This improves the slider's response to horizontal inertial forces, avoids deviations in the beam emission and reception angles of the sonar, and thus ensures the slider's displacement in the horizontal direction, thereby ensuring the horizontal detection range of the sonar. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the unmanned vessel of the present invention; Figure 2 This is a schematic diagram of the reef obstacle avoidance device of the present invention; Figure 3 This is a top view of the reef obstacle avoidance device of the present invention; Figure 4 for Figure 3 AA section view in the middle; Figure 5 This is a left half-sectional view of the unmanned vessel of the present invention during pitching. Figure 6 This is a frontal full sectional view of the unmanned vessel of the present invention when it rolls. Figure 7 This is a schematic diagram illustrating the usage process of the unmanned vessel obstacle avoidance device for marine reefs according to the present invention.

[0024] In the diagram: 1. Hull; 2. Sonar; 301. Mounting base; 302. Horizontal adjustment spring; 303. Slider; 304. Base plate; 3041. Ball bearing; 305. Rocker arm; 3051. Ball joint No. 1; 306. Swing arm; 307. Ball joint No. 2; 308. Linear actuator; 3081. Drive unit; 3082. Actuator; 309. Vertical adjustment spring; 401. Fin plate; 402. Connecting rod. Detailed Implementation

[0025] Please see Figures 1 to 7 This invention provides an unmanned vessel obstacle avoidance device and method for reefs at sea, the technical solution of which is as follows: Please refer to Figure 1 and Figure 4 An unmanned surface vessel (USV) obstacle avoidance device for reefs at sea includes a sonar 2 installed on the lower side of the hull 1 and an electronic control unit installed inside the hull 1. The electronic control unit is used to process the echo signals received by the sonar 2. A slider 303 is elastically connected inside the hull 1. The slider 303 is equipped with a position and attitude adjustment component. A connecting rod 402 is connected to the lower end of the slider 303. The lower end of the connecting rod 402 is fixedly connected to the sonar 2.

[0026] For details, please refer to Figure 2 and Figure 4 The posture adjustment assembly includes a mounting base 301, horizontal adjustment springs 302, a base plate 304, vertical adjustment springs 309, a rocker arm 305, a swing arm 306, and a second ball joint 307. The mounting base 301 is fixedly connected to the hull 1. The base plate 304 is located below the mounting base 301, and the two are connected by four vertical adjustment springs 309. Six horizontal adjustment springs 302 are fixedly installed on the inner wall of the mounting base 301. Both the vertical adjustment springs 309 and the horizontal adjustment springs 302 are evenly distributed in an array around the central circumference of the mounting base 301. The slider 303 is set inside the mounting base 301, and the ends of the four horizontal adjustment springs 302 near the center of the mounting base 301 are all fixedly connected to the slider 303. The geometric center of the slider 303 coincides with the center of gravity. A rocker arm 305 is ball-hinged to the center of the lower end face of the slider 303. The lower end of the rocker arm 305 is threadedly connected to the connecting rod 402. A first ball joint 3051 is provided in the middle section of the rocker arm 305. A swing arm 306 is hinged to the first ball joint 3051. Both ends of the swing arm 306 are ball-head structures. A second ball joint 307 is hinged to the end of the swing arm 306 away from the rocker arm 305. The second ball joint 307 is fixedly connected to the hull 1.

[0027] For further details, please refer to... Figure 1 and Figure 2The mounting base 301 is located at the front 1 / 3 of the length of the hull 1. The sonar 2 is rotatably connected to the left and right sides with fins 401. The sonar 2 is equipped with a geared motor that drives the rotation of the two fins 401 respectively. The rotation axis of the fins 401 intersects and is perpendicular to the rotation axis of the rocker arm 305. The geared motor is electrically connected to the electronic control unit. The geared motor is a worm gear geared motor. The rotation axis of the two fins 401 intersects and is perpendicular to the rotation axis of the rocker arm 305.

[0028] It is worth noting that in some embodiments, the mounting base 301 can be located at the front 1 / 3 to 1 / 2 of the length of the hull 1. This is because when the mounting base 301 is located at the rear of the hull 1, the distance between the sonar 2 and the propulsion device at the stern of the hull 1 is too close. During the movement of the hull 1, the noise generated by the propulsion device at the stern of the hull 1 can easily interfere with the information of the sonar 2, thereby affecting the detection accuracy of the sonar 2. When the mounting base 301 is located beyond the front 1 / 3 of the hull 1, the front of the hull 1 will generate waves during the movement of the hull 1, and the sound of the waves can also easily interfere with the information of the sonar 2, thereby affecting the detection accuracy of the sonar 2. In addition, the front of the hull 1 often adopts a curved surface design. During the movement of the hull 1 and when it is affected by wind and waves, the swing amplitude of the front of the hull 1 is large in the middle of the hull 1, which is not conducive to controlling the attitude of the sonar 2.

[0029] Please refer to Figure 5 It is easy to understand that when the hull 1 is pitched and swayed by the waves, the slider 303 is subjected to inertial force and undergoes vertical displacement within the mounting base 301. At the same time, it compresses or stretches the vertical adjustment spring 309, and the upper end of the rocker arm 305 moves along with the slider 303. Since the middle part of the rocker arm 305 is hinged to the swing arm 306 through the first ball joint 3051, and the swing arm 306 is fixedly connected to the hull 1 through the second joint, the first ball joint 3051 forms a lever point. At this time, the sonar 2 follows the slider 303 and undergoes relative displacement with the hull 1, so the height distance between the connecting rod 402 and the sea level remains unchanged. This avoids changes in the shape and intensity of the echo signal caused by changes in the height of the sonar 2 and the sea level, thus ensuring the detection effect of the sonar 2 on small targets.

[0030] It is worth noting that when the hull 1 is subjected to pitching and heaving motions by the waves, the fin plate 401 enhances the vertical resistance of the sonar 2 in the seawater, further preventing changes in the shape and intensity of the echo signal caused by changes in the height of the sonar 2 relative to the sea level, thus ensuring the detection effect of the sonar 2 on small targets.

[0031] It is also worth noting that the mounting base 301 is located at the front 1 / 3 of the length of the hull 1, which reduces the impact of the propulsion noise at the stern of the hull 1 on the sonar 2 signal. Furthermore, during the operation of the unmanned vessel, the electronic control unit adjusts the angle between the two side fins 401 and the sea level according to the speed of the hull 1. It uses the forward thrust of the hull 1 during movement to press down the front of the hull 1, thereby reducing the sway amplitude of the hull 1 during pitching. This further prevents the beam transmission angle and beam reception angle of the sonar 2 from shifting, thus ensuring the horizontal detection range of the sonar 2.

[0032] Furthermore, the fin 401 presses down the front of the hull 1, reducing the windward area of ​​the front of the hull 1, thereby reducing the intensity of the waves at the front of the hull 1. This reduces the interference of the wave noise at the front of the hull 1 on the sonar 2 signal, thus ensuring the detection accuracy of the sonar 2 for small targets.

[0033] For further details, please refer to... Figure 3 and Figure 4 The base plate 304 is also provided with multiple balls 3041, and when the slider 303 is displaced by inertial force, there are at least 4 balls 3041 in the vertical projection plane of the slider 303; thus, the sliding friction between the slider 303 and the base plate 304 is transformed into the rolling friction between the slider 303 and the balls 3041, which improves the response effect of the slider 303 to horizontal inertial force, thereby ensuring the displacement effect of the slider 303 in the horizontal direction, and thus ensuring the horizontal detection range of the sonar 2.

[0034] Please refer to Figure 6It should also be understood that when the hull 1 rolls due to the action of waves, the slider 303 is subjected to inertial force, causing horizontal and vertical displacement within the mounting base 301, and compressing the horizontal adjusting spring 302 and the vertical adjusting spring 309 located on the side of the direction of movement. The upper end of the rocker arm 305 moves along with the slider 303. Since the middle part of the rocker arm 305 is hinged to the swing arm 306 through the first ball joint 3051, and the swing arm 306 is fixedly connected to the hull 1 through the second hinge joint, the first ball joint 3051 forms a lever point. At this time, the direction of movement of the lower end of the rocker arm 305 is opposite to the direction of movement of the slider 303, and the sonar 2 moves along with the lower end of the rocker arm 305. Therefore, when the hull 1 rolls due to the sea waves, the angle between the bottom surface of the hull 1 and the sea level changes. The connecting rod 402, following the slider 303, swings around the ball joint 3051 as the fulcrum. This keeps the axis of the connecting rod 402 perpendicular to the sea level, while maintaining a constant height distance between the connecting rod 402 and the sea level. This ensures that the detection direction of the sonar 2 does not shift with the rolling of the hull 1, preventing shifts in the beam emission and reception angles of the sonar 2. It also ensures the horizontal detection range of the sonar 2 and prevents changes in the shape and intensity of the echo signal caused by changes in the height of the sonar 2 relative to the sea level, thus guaranteeing the detection effect of the sonar 2 on small targets.

[0035] It is worth noting that, please refer to Figure 2 The vertical projection surface of the connecting rod 402 is elliptical, and the major axis of the ellipse faces directly forward of the hull 1. The center of gravity of the connecting rod 402 coincides with the rotation axis of the rocker arm 305. This reduces the resistance between the connecting rod 402 and the seawater when the hull 1 is moving. At the same time, the seawater passes through the surface of the connecting rod 402, which reduces the turbulence behind the connecting rod 402, thereby reducing the vibration of the connecting rod 402 during the movement of the hull 1, and thus reducing the impact of vibration and vibration noise on the sonar 2 signal.

[0036] Furthermore, when the hull 1 sways due to wind and waves, the elliptical cross-section of the connecting rod 402 increases the lateral resistance between the connecting rod 402 and the seawater, thereby reducing the lateral sway amplitude of the hull 1. This reduces the impact of the hull 1's sway on the sonar 2's attitude, further preventing the sonar 2's beam emission angle and beam reception angle from shifting, thus ensuring the sonar 2's horizontal detection range and detection accuracy.

[0037] Furthermore, during the unmanned vessel's movement at sea, sonar 2 is subject to seawater resistance, and the connecting rod 402 is not perpendicular to the sea surface. If the unmanned vessel's speed is V1 and V1 does not change, the detection results of sonar 2 will not be affected. However, when the unmanned vessel's speed changes from V1 to V2, the slider 303 can adjust the angle of the connecting rod 402 during the speed change. But when the unmanned vessel maintains V2, the angle between the connecting rod 402 and the bottom surface of the hull 1 changes. At this time, the detection angle of sonar 2 changes, which can easily cause the horizontal detection range of sonar 2 to shrink.

[0038] Therefore, please refer to Figure 2 and Figure 4 A linear actuator 308 is fixedly installed at the front end of the fixed base. The linear actuator 308 includes a drive part 3081 and an execution part 3082. The drive part 3081 is fixedly connected to the mounting base 301. The drive part 3081 and the execution part 3082 are slidably connected coaxially. The end of the execution part 3082 away from the drive part 3081 is elastically connected to the outer wall of the slider 303. When the slider 303 is in the initial position, the axis of the execution part 3082 passes through the center of the slider 303. The drive part 3081 is electrically connected to the electronic control unit.

[0039] In this embodiment, the drive unit 3081 is a drive motor, and the execution unit 3082 is a push rod. Thus, during the movement of the unmanned vessel, the electronic control unit detects the running speed of the hull 1 and controls the distance between the execution unit 3082 and the slider 303 according to the running speed of the hull 1, thereby changing the initial position of the slider 303. This compensates for the angle changes between the connecting rod 402 and the sea level of the hull 1 at different running speeds of the unmanned vessel, ensuring that the axis of the connecting rod 402 remains perpendicular to the sea level. This avoids the beam transmission angle and beam reception angle of the sonar 2 from shifting, thus ensuring the horizontal detection range of the sonar 2.

[0040] It is worth noting that in some other embodiments, the linear actuator 308 may also be any of the following: a hydraulic cylinder, a pneumatic cylinder, a linear motor, and a gear and rack structure, which will not be described in detail here.

[0041] Please refer to Figure 7 A method for using an unmanned surface vessel (USV) obstacle avoidance device for reefs at sea includes the following steps: S1: The electronic control unit controls the operation of the hull 1, connects the power supply lines of the linear actuator 308 and the geared motor, and simultaneously starts the sonar 2; S2: The electronic control unit adjusts the distance between the actuator 3082 and the slider 303 according to the real-time running speed of the hull 1, and at the same time adjusts the angle between the fin plate 401 and the sea surface; S3: The sonar 2 acquires echo signals and transmits the signal data to the electronic control unit. The electronic control unit analyzes and processes the received signal data and constructs an environmental topographic map including the location and geometric information of reefs, obstacles, and organisms. S4: The electronic control unit uses algorithms to detect and identify potential obstacles, and determines whether underwater reefs, obstacles or organisms are on the unmanned vessel's path or pose a threat to the hull 1. Based on the environmental map and obstacle detection results, the electronic control unit performs path planning and obstacle avoidance strategy calculations, including determining a safe path, avoiding collisions, and adjusting the sailing speed. Through algorithms and decision-making logic, a safe and feasible sailing path is generated. S5: The electronic control unit adjusts the direction of travel and speed of the hull 1 according to the path planning and obstacle avoidance strategy, so that the hull 1 avoids reefs and other obstacles during the voyage. S6: The sonar 2 continues to monitor the surrounding underwater environment and transmits the acquired echo signals to the electronic control unit. If new obstacles or targets appear during navigation, the electronic control unit updates the environmental map and adjusts the path planning and obstacle avoidance strategy accordingly to maintain the safety of the unmanned vessel. S7: After the detection mission is completed, the electronic control unit controls the hull 1 to stop running and cuts off the power supply lines of the linear actuator 308 and the geared motor, while simultaneously shutting down the sonar 2.

[0042] Although specific embodiments of the present invention have been shown and described above, it is understood that the above embodiments are merely exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions, and variations to the above embodiments within the scope of the present invention, and all such modifications, alterations, substitutions, and variations should be included within the protection scope of the present invention without departing from the principles of the present invention.

Claims

1. An unmanned surface vessel (USV) obstacle avoidance device for reefs at sea, comprising a sonar (2) disposed on the underside of the hull (1) and an electronic control unit disposed within the hull (1), wherein the electronic control unit is used to process the echo signal received by the sonar (2), characterized in that, It also includes a slider (303) and a pose adjustment component. The slider (303) is elastically connected inside the hull (1), and the slider (303) can move in both the horizontal and vertical directions. The slider (303) is provided with a pose adjustment component. The lower end of the slider (303) is connected to a connecting rod (402). The lower end of the connecting rod (402) is fixedly connected to the sonar (2). When the hull (1) is tossed by wind and waves, the slider (303) is subjected to inertial force and undergoes relative displacement with the pose adjustment component. When the slider (303) loses the inertial force, the pose adjustment component drives the slider (303) to reset. When the slider (303) moves, the slider (303) drives the connecting rod (402) to rotate around the pose adjustment component and keeps the connecting rod (402) perpendicular to the sea level, while maintaining the vertical distance between the sonar (2) and the sea level. The posture adjustment assembly includes a mounting base (301), a horizontal adjustment spring (302), a base plate (304), a vertical adjustment spring (309), a rocker arm (305), a swing arm (306), and a second ball joint (307). The mounting base (301) is fixedly connected to the hull (1). The base plate (304) is located below the mounting base (301), and the two are connected by the vertical adjustment spring (309). A horizontal adjustment spring (302) is fixedly installed on the inner wall of the mounting base (301). The number of both the vertical adjustment spring (309) and the horizontal adjustment spring (302) is at least 3. Both the vertical adjustment spring (309) and the horizontal adjustment spring (302) are evenly distributed in an array around the central circumference of the mounting base (301). The slider (305) 03) Set in the mounting base (301), and the ends of the multiple horizontal adjustment springs (302) near the center of the mounting base (301) are fixedly connected to the slider (303). The geometric center of the slider (303) coincides with the center of gravity. The lower end face of the slider (303) is ball-jointed with a rocker arm (305). The lower end of the rocker arm (305) is threadedly connected to the connecting rod (402). The middle section of the rocker arm (305) is provided with a first ball joint (3051). The first ball joint (3051) is hinged with a swing arm (306). Both ends of the swing arm (306) are ball head structures. The end of the swing arm (306) away from the rocker arm (305) is hinged with a second ball joint (307). The second ball joint (307) is fixedly connected to the hull (1). A linear actuator (308) is fixedly mounted on the front end of the mounting base (301). The linear actuator (308) includes a drive unit (3081) and an execution unit (3082). The drive unit (3081) is fixedly connected to the mounting base (301). The drive unit (3081) and the execution unit (3082) are slidably connected coaxially. One end of the execution unit (3082) away from the drive unit (3081) is elastically connected to the outer wall of the slider (303). When the slider (303) is in the initial position, the axis of the execution unit (3082) passes through the center of the slider (303). The drive unit (3081) is electrically connected to the electronic control unit. The electronic control unit adjusts the distance between the execution unit (3082) and the slider (303) according to the speed of the hull (1).

2. The unmanned vessel obstacle avoidance device for marine reefs according to claim 1, characterized in that: The base plate (304) is also provided with at least 4 balls (3041), the lower end face of the slider (303) is in rolling connection with the balls (3041), the slider (303) and the base plate (304) are connected by magnetic force, and the balls (3041) are made of non-magnetic material.

3. The unmanned vessel obstacle avoidance device for marine reefs according to claim 1, characterized in that: The mounting base (301) is located at the front 1 / 3 to 1 / 2 of the length of the hull (1). The sonar (2) is rotatably connected to fins (401) on both sides. The sonar (2) is equipped with a reduction motor that drives the fins (401) on both sides to rotate. The rotation axis of the fins (401) intersects and is perpendicular to the rotation axis of the rocker arm (305). The reduction motor is electrically connected to the electronic control unit. The electronic control unit adjusts the angle between the fins (401) on both sides and the sea level according to the speed of the hull (1).

4. The unmanned vessel obstacle avoidance device for marine reefs according to claim 3, characterized in that: The vertical projection surface of the connecting rod (402) is elliptical, and the major axis of the ellipse faces the front of the hull (1). The center of gravity of the connecting rod (402) coincides with the rotation axis of the rocker arm (305).

5. The method of using the unmanned vessel reef avoidance device according to any one of claims 1 to 4, characterized in that, Includes the following steps: S1: The electronic control unit controls the operation of the hull (1), connects the power supply lines of the linear actuator (308) and the geared motor, and starts the sonar (2) at the same time. S2: The electronic control unit adjusts the distance between the actuator (3082) and the slider (303) according to the real-time running speed of the hull (1), and at the same time adjusts the angle between the fin plate (401) and the sea surface; S3: The sonar (2) acquires echo signals and transmits the signal data to the electronic control unit. The electronic control unit analyzes and processes the received signal data and constructs an environmental topographic map including the location and geometric information of reefs, obstacles, and organisms. S4: The electronic control unit uses algorithms to detect and identify potential obstacles, and determines whether underwater reefs, obstacles or organisms are on the unmanned vessel's path or pose a threat to the hull (1). Based on the environmental map and obstacle detection results, the electronic control unit performs path planning and obstacle avoidance strategy calculation, including determining a safe path, avoiding collisions, and adjusting the sailing speed. Through algorithms and decision logic, a safe and feasible sailing path is generated. S5: The electronic control unit adjusts the direction of travel and speed of the hull (1) according to the path planning and obstacle avoidance strategy, so that the hull (1) avoids reefs and other obstacles during the voyage. S6: The sonar (2) continues to monitor the surrounding underwater environment and transmits the acquired echo signals to the electronic control unit. When new obstacles or targets appear during navigation, the electronic control unit updates the environmental map and adjusts the path planning and obstacle avoidance strategy accordingly to maintain the safety of the unmanned vessel. S7: After the detection mission is completed, the electronic control unit controls the hull (1) to stop running and cuts off the power supply lines of the linear actuator (308) and the geared motor, while shutting down the sonar (2).

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