Methods, systems, media and equipment for controlling the circular motion of unmanned surface vessels

Abstract

This invention provides a method, system, medium, and device for controlling the circular motion of an unmanned surface vessel (USV), comprising: Step 1: setting a circular path and determining the center, radius, and direction of motion; Step 2: using the target heading at the current position as the direction of the vector, where C is the current position of the USV, S is the target point of the USV, a velocity v is set, and the USV moves along the target heading, then performs linear guidance according to the LOS guidance law; Step 3: establishing a model of the USV's horizontal maneuvering motion on still water; Step 4: setting the yaw angle of the controller USV in the model, obtaining the torque output by the model, thereby enabling the USV to navigate along a circular path. This invention is applicable not only to unmanned surface vessels but also to unmanned vehicles, drones, etc.; by eliminating accumulated errors and adding feedforward terms, the trajectory error between the actual circular motion and the standard circle can be reduced, enabling precise control of the circular trajectory.

Description

Technical Field

[0001] This invention relates to the field of unmanned vessel control technology, specifically to a method, system, medium, and equipment for controlling the circular motion of an unmanned vessel. Background Technology

[0002] With the rapid development of the information and intelligent era, unmanned surface vessels (USVs), as a cutting-edge maritime transportation tool, have demonstrated enormous application potential in multiple fields, including oil exploration, marine surveying, and marine monitoring. However, limited by current technology and design capabilities, USVs often exhibit underactuated characteristics, meaning their control inputs are less than the dimension of the system state. This characteristic necessitates advanced control algorithms to ensure stable operation and precise autonomous navigation during unmanned surface vessel (USV) navigation. In the field of USV motion control, this problem can be categorized into three main types: stabilization control, trajectory tracking control, and path tracking control. It is worth noting that when ships navigate on water, the emphasis is not on arriving at a specific location at a specific time, but rather on following a predetermined route. Therefore, designing a highly reliable and accurate path tracking control system is particularly important.

[0003] Generally, path tracking for unmanned surface vessels (USVs) is divided into two modules: guidance and control. The line-of-sight (LOS) method is widely used in the design of guidance subsystems due to its simplicity. However, the LOS guidance law is usually only applicable to linear guidance, and special design is required for circular motion guidance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method, system, medium, and device for controlling the circular motion of an unmanned vessel.

[0005] The unmanned surface vessel circular motion control method provided by the present invention includes:

[0006] Step 1: Set the circular path, determine the center, radius and direction of movement;

[0007] Step 2: Use the target heading at the current position as a vector. The direction is set, C is the current position of the unmanned vessel, S is the target point of the unmanned vessel, the speed is set to v, and it moves in the target heading, and then performs linear guidance according to the LOS guidance law;

[0008] Step 3: Establish a model of the USV's horizontal maneuvering motion on a still water surface;

[0009] Step 4: Set the yaw angle of the controller USV in the model to obtain the torque output by the model, thereby enabling the unmanned vessel to navigate along a circular path.

[0010] Preferably, step 1 includes: Let the current position of the unmanned vessel be C. If the current unmanned vessel is outside the set circle and the distance from the current position to the circumference of the circle is d, then draw a tangent line from the current position to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S; if the current unmanned vessel is inside the set circle and the distance from the current position to the circumference of the circle is d, then take an equidistant mapping point from the current position to the outside of the circle, draw a tangent line from the mapping point outside the circle to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S.

[0011] Preferably, step 2 includes:

[0012] Let the target path be COS, the current position of the unmanned surface vessel be C, and the forward-looking distance be L. Draw a circle with the forward-looking distance L as the radius, intersecting COS at the intersection point. Take the intersection point as the target point P. LOS Then we have:

[0013]

[0014] In the formula, C0 is the target position, x LOS y LOS For P LOS The coordinates of point C; x and y are the coordinates of point C; This is the heading angle of the unmanned vessel, used as the set value for the heading angle;

[0015] According to the stability control analysis, there is a cumulative deviation in the steady state. Therefore, a control term needs to be added based on the cumulative deviation. Since circular motion has a heading tendency, an initial feedforward term is added. This feedforward term is related to the circular track radius R and the unmanned surface vessel speed v. The output control quantity is as follows:

[0016]

[0017] Where, φ d p is the final heading angle setpoint control value. I p is the control coefficient for deviation d, k is the control coefficient for the feedforward term, and p is the control coefficient for the feedforward term. I k is an adjustable constant.

[0018] Preferably, step 3 includes:

[0019] By decoupling the system and establishing the controller, setting the longitudinal speed constant, and designing the controller only for steering control, we have:

[0020]

[0021] In the formula: m is the mass of the hull itself, m x m y I represents the additional mass along the x-axis and y-axis, respectively. zz J zzLet be the moment of inertia about the z-axis; X, Y, and N represent the forces along the x and y axes and the torque about the z-axis in the hull coordinate system, respectively; H and P represent the forces and torques provided by the hull itself and the propeller, respectively; u, v, and r are the velocity components of the hull, corresponding to the rotational angular velocities along the x, y, and z axes, respectively. The time derivative of the velocity component;

[0022] The PID control expression is as follows:

[0023] Δu(k)=u(k)-u(k-1)

[0024] =K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)]

[0025] In the formula, u(k) is the control quantity output by the controller; for heading control, u(k) is the main engine speed; for speed control, u(k) is the rudder angle. p For proportional gain; K I K is the integral coefficient; D is the differential coefficient; e(k) is the deviation.

[0026] The unmanned surface vessel circular motion control system provided by the present invention includes:

[0027] Module M1: Sets the circular path, determining the center, radius, and direction of movement;

[0028] Module M2: Uses the target heading at the current position as a vector. The direction is set, C is the current position of the unmanned vessel, S is the target point of the unmanned vessel, the speed is set to v, and it moves in the target heading, and then performs linear guidance according to the LOS guidance law;

[0029] Module M3: Establishes a model for the horizontal maneuvering motion of the USV on a still water surface;

[0030] Module M4: Set the yaw angle of the controller USV in the model to obtain the torque output by the model, thereby enabling the unmanned vessel to navigate along a circular path.

[0031] Preferably, the module M1 includes: assuming the current position of the unmanned vessel is C, if the current unmanned vessel is outside a set circle and the distance from the current position to the circumference is d, then a tangent line is drawn from the current position to the circumference to obtain a tangent point S, and the target point of the unmanned vessel is set as the tangent point S; if the current unmanned vessel is inside a set circle and the distance from the current position to the circumference is d, then an equidistant mapping point is taken from the current position to the outside of the circle, and a tangent line is drawn from the mapping point outside the circle to the circumference to obtain a tangent point S, and the target point of the unmanned vessel is set as the tangent point S.

[0032] Preferably, the module M2 includes:

[0033] Let the target path be COS, the current position of the unmanned surface vessel be C, and the forward-looking distance be L. Draw a circle with the forward-looking distance L as the radius, intersecting COS at the intersection point. Take the intersection point as the target point P. LOS Then we have:

[0034]

[0035] In the formula, C0 is the target position, x LOS y LOS For P LOS The coordinates of point C; x and y are the coordinates of point C; This is the heading angle of the unmanned vessel, used as the set value for the heading angle;

[0036] According to the stability control analysis, there is a cumulative deviation in the steady state. Therefore, a control term needs to be added based on the cumulative deviation. Since circular motion has a heading tendency, an initial feedforward term is added. This feedforward term is related to the circular track radius R and the unmanned surface vessel speed v. The output control quantity is as follows:

[0037]

[0038] Where, φ d p is the final heading angle setpoint control value. I p is the control coefficient for deviation d, k is the control coefficient for the feedforward term, and p is the control coefficient for the feedforward term. I k is an adjustable constant.

[0039] Preferably, the module M3 includes:

[0040] By decoupling the system and establishing the controller, setting the longitudinal speed constant, and designing the controller only for steering control, we have:

[0041]

[0042] In the formula: m is the mass of the hull itself, m x m y I represents the additional mass along the x-axis and y-axis, respectively. zz J zz Let be the moment of inertia about the z-axis; X, Y, and N represent the forces along the x and y axes and the torque about the z-axis in the hull coordinate system, respectively; H and P represent the forces and torques provided by the hull itself and the propeller, respectively; u, v, and r are the velocity components of the hull, corresponding to the rotational angular velocities along the x, y, and z axes, respectively. The time derivative of the velocity component;

[0043] The PID control expression is as follows:

[0044] Δu(k)=u(k)-u(k-1)

[0045] =K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)]

[0046] In the formula, u(k) is the control output of the controller; for heading control, u(k) is the main engine speed; for speed control, u(k) is the rudder angle; K p For proportional gain; K I K is the integral coefficient; D is the differential coefficient; e(k) is the deviation.

[0047] According to the computer-readable storage medium storing a computer program provided by the present invention, when the computer program is executed by a processor, it implements the steps of the unmanned vessel circular motion control method.

[0048] The electronic device provided by the present invention includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, it implements the steps of the unmanned vessel circular motion control method.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] This invention provides a method for controlling the circular motion of an unmanned vessel, which is applicable not only to unmanned vessels, but also to unmanned vehicles, drones, etc. The center of the circle, the radius of the circular trajectory, and the direction of the circular motion can all be adjusted as needed. By eliminating cumulative errors and adding feedforward terms, the trajectory error between the actual circular motion and the standard circle can be reduced, thus enabling precise control of the circular trajectory. Attached Figure Description

[0051] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0052] Figure 1 This is the overall architecture of the circular control algorithm described in this invention;

[0053] Figure 2 This refers to the case where the current position of the circumferential control algorithm described in this invention is outside the circle;

[0054] Figure 3 This refers to the case where the current position of the circumferential control algorithm described in this invention is inside the circle;

[0055] Figure 4This is a schematic diagram of the LOS guidance rate of the circular control algorithm described in this invention;

[0056] Figure 5 This is the simulation effect of the circular motion trajectory in the specific implementation of the present invention;

[0057] Figure 6 This is a field image showing the implementation of the algorithm designed in this invention on an unmanned boat and the conduct of a circular motion experiment on a lake;

[0058] Figure 7 This is the effect of implementing the algorithm designed in a specific embodiment of the present invention on an unmanned boat and conducting a circular motion experiment on a lake. Detailed Implementation

[0059] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0060] Example 1

[0061] The circular path control algorithm architecture designed in this invention is as follows: Figure 1 As shown. This invention proposes a guidance law for the circular motion of an unmanned surface vessel (USV) based on tangential line-of-sight (LOS). It utilizes a line-of-sight guidance law for linear control, converting the USV's circular motion into linear motion for path control via the tangential method. The main steps are as follows:

[0062] Step 1: Set the circular path, determining the center, radius, and direction of movement. Let the current position of the unmanned surface vessel be C, such as... Figure 2 As shown, if the current unmanned surface vessel (USV) is outside the designated circle, and the distance from its current position to the circumference is d, then a tangent line is drawn from the current position to the circumference to obtain the tangency point S. The USV's target point is set as the tangency point S. For example... Figure 3 As shown, if the current unmanned vessel is within a set circle and the distance from the current position to the circumference of the circle is d, then take an equidistant mapping point from the current position to the outside of the circle, draw a tangent line from the mapping point outside the circle to the circumference of the circle, and obtain the tangent point S. Set the target point of the unmanned vessel as the tangent point S.

[0063] Step 2: The target heading at the current position is a vector. The direction is set, with a velocity v, moving towards the target heading, and then linear guidance is performed according to the LOS guidance law. The LOS guidance law is described below. Figure 4 As shown, assuming the target path is COS and the current position of the unmanned surface vessel is C, a forward-looking distance L is set. A circle is drawn with the forward-looking distance L as the radius, intersecting COS. This intersection point is taken as the target point P. LOS Then we have:

[0064]

[0065] In the formula, x LOS y LOS For P LOS The coordinates of point C are x and y; φ is the heading angle of the unmanned vessel, which is used as the set value for the heading angle.

[0066] At each moment, the positions of S and C0 are readjusted to the tangent point and the current position, thus ensuring that the unmanned vessel's heading is adjusted in real time in the circular direction, guaranteeing circular motion. Since the target point setting scheme described in step one always uses points on the circumference as the target point, the algorithm cannot truly reach those points during control. According to stability control analysis, there will always be a cumulative deviation in a stable state. Therefore, a control term needs to be added based on the cumulative error. Furthermore, since circular motion has a heading tendency, an initial feedforward term is added, which is related to the circular track radius R and the unmanned vessel's speed v. Therefore, the output control quantity is as follows:

[0067]

[0068] Where, φ d p is the final heading angle setpoint control value. I p is the control coefficient for deviation d, k is the control coefficient for the feedforward term, and p is the control coefficient for the feedforward term. I k is an adjustable constant.

[0069] Step 3: Establish a model of the USV's horizontal maneuvering motion on still water. Decouple the system and establish the controller, assuming the longitudinal velocity is constant, and design the controller only for steering control.

[0070]

[0071] Where: m x m y J zz These represent the additional mass and the additional inertial torque, respectively. X, Y, and N are the forces along the x and y axes and the torque about the z axis in the hull coordinate system, respectively. H and P represent the forces and torques provided by the hull itself and the propeller, respectively.

[0072] The controller is designed based on the USV yaw angle model. This model is a first-order linear model, and the controller can be designed using various control methods such as linear quadratic regulator (LQR), proportional-integral-derivative (PID) controller, model predictive control (MPC), active disturbance rejection control (ADRC), and sliding mode control (SMC).

[0073] The PID control expression is as follows:

[0074] Δu(k)=u(k)-u(k-1)

[0075] =K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)]

[0076] In the formula, u(k) is the control output of the controller; for heading control, u(k) is the main engine speed; for speed control, u(k) is the rudder angle; K p For proportional gain; K I K is the integral coefficient; D Here, e is the differential coefficient; e(k) is the error, and for heading control, e(k) = ψ. los -ψ u .

[0077] Step 4: Set the controller USV yaw angle to φ. d The output torque τ is obtained. r =Δu(k), thereby enabling the unmanned vessel to navigate along a circular path with high precision in circular trajectory control.

[0078] This specific embodiment is a control system designed using a precise control method for the circular motion of an unmanned vessel for circular synthetic aperture imaging proposed in this invention, and the control system is applied to an unmanned vessel prototype to conduct circular motion tests on a lake.

[0079] A model of the unmanned surface vessel prototype manufactured in this embodiment is established. Based on the control algorithm designed in this embodiment, a simulation of the unmanned surface vessel's circular motion control algorithm is performed. The simulation results of the circular path tracking are as follows: Figure 5 As shown.

[0080] Simulation results show that the USV prototype control algorithm designed according to this embodiment has a tracking deviation of less than 0.2m in the circular trajectory, and the tracking effect is good.

[0081] Based on the simulation results, the algorithm designed in this embodiment is implemented in the USV prototype control system. Then, the USV described in this embodiment is subjected to a lake test, as follows: Figure 6 As shown. The results of the circular motion experiment on the lake are as follows. Figure 7 As shown.

[0082] Analysis of the USV prototype's circular motion results showed that the circular path tracking error was within 0.7m, indicating good tracking performance. The horizontal attitude changed little during the motion, and the heading angle change conformed to the circular motion process.

[0083] Example 2

[0084] The present invention also provides an unmanned vessel circular motion control system, which can be implemented by executing the process steps of the unmanned vessel circular motion control method. That is, those skilled in the art can understand the unmanned vessel circular motion control method as a preferred embodiment of the unmanned vessel circular motion control system.

[0085] The unmanned surface vessel circular motion control system provided by the present invention includes: module M1: setting the circular path and determining the center, radius, and direction of motion; module M2: using the target heading at the current position as a vector. The direction is set, C is the current position of the unmanned vessel, S is the target point of the unmanned vessel, the speed v is set, and the vessel moves in the target heading. Then, it performs linear guidance according to the LOS guidance law. Module M3: Establishes a model of the USV's horizontal maneuvering motion on still water. Module M4: Sets the yaw angle of the controller USV in the model, obtains the torque output by the model, and then realizes the unmanned vessel's navigation along a circular path.

[0086] The module M1 includes: Let the current position of the unmanned vessel be C. If the current unmanned vessel is outside a set circle and the distance from the current position to the circumference of the circle is d, then draw a tangent line from the current position to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S; if the current unmanned vessel is inside the set circle and the distance from the current position to the circumference of the circle is d, then take an equidistant mapping point from the current position to the outside of the circle, draw a tangent line from the mapping point outside the circle to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S.

[0087] The module M2 includes: setting the target path as COS, the current position of the unmanned vessel as C, setting the forward look-ahead distance L, drawing a circle with the forward look-ahead distance L as the radius, intersecting COS, and taking the intersection point as the target point P. LOS Then we have:

[0088]

[0089] In the formula, C0 is the target position, x LOS y LOS For P LOS The coordinates of point C; x and y are the coordinates of point C; This is the heading angle of the unmanned vessel, used as the set value for the heading angle;

[0090] According to the stability control analysis, there is a cumulative deviation in the steady state. Therefore, a control term needs to be added based on the cumulative deviation. Since circular motion has a heading tendency, an initial feedforward term is added. This feedforward term is related to the circular track radius R and the unmanned surface vessel speed v. The output control quantity is as follows:

[0091]

[0092] Where, φ d p is the final heading angle setpoint control value. I p is the control coefficient for deviation d, k is the control coefficient for the feedforward term, and p is the control coefficient for the feedforward term. I k is an adjustable constant.

[0093] The module M3 includes: decoupling the system and establishing the controller. If the longitudinal speed is kept constant, and the controller design is only performed for steering control, then:

[0094]

[0095] In the formula: m is the mass of the hull itself, m x m y I represents the additional mass along the x-axis and y-axis, respectively. zz J zz Let be the moment of inertia about the z-axis; X, Y, and N represent the forces along the x and y axes and the torque about the z-axis in the hull coordinate system, respectively; H and P represent the forces and torques provided by the hull itself and the propeller, respectively; u, v, and r are the velocity components of the hull, corresponding to the rotational angular velocities along the x, y, and z axes, respectively. The time derivative of the velocity component;

[0096] The PID control expression is as follows:

[0097] Δu(k)=u(k)-u(k-1)

[0098] =K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)]

[0099] In the formula, u(k) is the control quantity output by the controller; for heading control, u(k) is the main engine speed; for speed control, u(k) is the rudder angle. p For proportional gain; K I K is the integral coefficient; D is the differential coefficient; e(k) is the deviation.

[0100] Those skilled in the art will understand that, in addition to implementing the system, apparatus, and their modules provided by this invention in purely computer-readable program code, the same program can be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system, apparatus, and their modules provided by this invention can be considered a hardware component, and the modules included therein for implementing various programs can also be considered structures within the hardware component; alternatively, modules for implementing various functions can be considered both software programs implementing the method and structures within the hardware component.

[0101] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for controlling the circular motion of an unmanned surface vessel, characterized in that, include: Step 1: Set the circular path, determine the center, radius and direction of movement; Step 2: Use the target heading at the current position as a vector. The direction is set, C is the current position of the unmanned vessel, S is the target point of the unmanned vessel, the speed is set to v, and it moves in the target heading, and then performs linear guidance according to the LOS guidance law; Step 3: Establish a model of the USV's horizontal maneuvering motion on a still water surface; Step 4: Set the yaw angle of the controller USV in the model to obtain the torque output by the model, thereby enabling the unmanned vessel to navigate along a circular path; Step 1 includes: Let the current position of the unmanned vessel be C. If the unmanned vessel is outside the set circle and the distance from the current position to the circumference of the circle is d, then draw a tangent line from the current position to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S; if the unmanned vessel is inside the set circle and the distance from the current position to the circumference of the circle is d, then take an equidistant mapping point from the current position to the outside of the circle, draw a tangent line from the mapping point outside the circle to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S. Step 2 includes: Let the target path be COS, the current position of the unmanned surface vessel be C, and the forward-looking distance be L. Draw a circle with the forward-looking distance L as the radius, intersecting COS at the intersection point. Take the intersection point as the target point P. LOS Then we have: In the formula, C0 is the target position, x LOS y LOS For P LOS The coordinates of point C; x and y are the coordinates of point C; This is the heading angle of the unmanned vessel, used as the set value for the heading angle; According to the stability control analysis, there is a cumulative deviation in the steady state. Therefore, a control term needs to be added based on the cumulative deviation. Since circular motion has a heading tendency, an initial feedforward term is added. This feedforward term is related to the circular track radius R and the unmanned surface vessel speed v. The output control quantity is as follows: Where, φ d p is the final heading angle setpoint control value. I p is the control coefficient for deviation d, k is the control coefficient for the feedforward term, and p is the control coefficient for the feedforward term. I k is an adjustable constant.

2. The unmanned surface vessel circular motion control method according to claim 1, characterized in that, Step 3 includes: By decoupling the system and establishing the controller, setting the longitudinal speed constant, and designing the controller only for steering control, we have: In the formula: m is the mass of the hull itself, m x m y I represents the additional mass along the x-axis and y-axis, respectively. zz J zz Let be the moment of inertia about the z-axis; X, Y, and N represent the forces along the x and y axes and the torque about the z-axis in the hull coordinate system, respectively; H and P represent the forces and torques provided by the hull itself and the propeller, respectively; u, v, and r are the velocity components of the hull, corresponding to the rotational angular velocities along the x, y, and z axes, respectively. The time derivative of the velocity component; The PID control expression is as follows: Δu(k)=u(k)-u(k-1) =K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)] In the formula, u(k) is the control quantity output by the controller; for heading control, u(k) is the main engine speed; for speed control, u(k) is the rudder angle. p For proportional gain; K I K is the integral coefficient; D is the differential coefficient; e(k) is the deviation.

3. A circular motion control system for an unmanned surface vessel, characterized in that, include: Module M1: Sets the circular path, determining the center, radius, and direction of movement; Module M2: Uses the target heading at the current position as a vector. The direction is set, C is the current position of the unmanned vessel, S is the target point of the unmanned vessel, the speed is set to v, and it moves in the target heading, and then performs linear guidance according to the LOS guidance law; Module M3: Establishes a model for the horizontal maneuvering motion of the USV on a still water surface; Module M4: Set the yaw angle of the controller USV in the model to obtain the torque output by the model, thereby enabling the unmanned vessel to navigate along a circular path; The module M1 includes: Let the current position of the unmanned vessel be C. If the current unmanned vessel is outside a set circle and the distance from the current position to the circumference of the circle is d, then draw a tangent line from the current position to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S; if the current unmanned vessel is inside a set circle and the distance from the current position to the circumference of the circle is d, then take an equidistant mapping point from the current position to the outside of the circle, draw a tangent line from the mapping point outside the circle to the circumference of the circle to obtain the tangent point S, and set the target point of the unmanned vessel as the tangent point S. The module M2 includes: Let the target path be COS, the current position of the unmanned surface vessel be C, and the forward-looking distance be L. Draw a circle with the forward-looking distance L as the radius, intersecting COS at the intersection point. Take the intersection point as the target point P. LOS Then we have: In the formula, C0 is the target position, x LOS y LOS For P LOS The coordinates of point C; x and y are the coordinates of point C; This is the heading angle of the unmanned vessel, used as the set value for the heading angle; According to the stability control analysis, there is a cumulative deviation in the steady state. Therefore, a control term needs to be added based on the cumulative deviation. Since circular motion has a heading tendency, an initial feedforward term is added. This feedforward term is related to the circular track radius R and the unmanned surface vessel speed v. The output control quantity is as follows: Where, φ d p is the final heading angle setpoint control value. I p is the control coefficient for deviation d, k is the control coefficient for the feedforward term, and p is the control coefficient for the feedforward term. I k is an adjustable constant.

4. The unmanned vessel circular motion control system according to claim 3, characterized in that, The module M3 includes: By decoupling the system and establishing the controller, setting the longitudinal speed constant, and designing the controller only for steering control, we have: In the formula: m is the mass of the hull itself, m x m y I represents the additional mass along the x-axis and y-axis, respectively. zz J zz Let be the moment of inertia about the z-axis; X, Y, and N represent the forces along the x and y axes and the torque about the z-axis in the hull coordinate system, respectively; H and P represent the forces and torques provided by the hull itself and the propeller, respectively; u, v, and r are the velocity components of the hull, corresponding to the rotational angular velocities along the x, y, and z axes, respectively. The time derivative of the velocity component; The PID control expression is as follows: Δu(k)=u(k)-u(k-1) =K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)] In the formula, u(k) is the control output of the controller; for heading control, u(k) is the main engine speed; for speed control, u(k) is the rudder angle; K p For proportional gain; K I K is the integral coefficient; D is the differential coefficient; e(k) is the deviation.

5. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the unmanned vessel circular motion control method according to claim 1 or 2.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is executed by the processor, it implements the steps of the unmanned vessel circular motion control method according to claim 1 or 2.

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