An unmanned surface vehicle system with fast maneuvering and anti-interference steering auxiliary system

Abstract

This invention relates to an unmanned surface vessel (USV) with a rapid maneuvering and anti-interference steering assistance system. By installing a jet engine and a simple engine turntable on the mast, aerodynamic thrust is provided to the hull in all directions, transferring steering power from underwater to above water, thus overcoming the influence of water flow resistance. The turntable can adjust to the target angle within milliseconds, rapidly changing the direction of steering power; the jet engine's power adjustment time is also very short, quickly changing the direction and magnitude of the steering power on the hull side. Based on a novel USV platform with added equipment, this invention has developed a control allocation strategy to maximize the efficiency of the two power systems. Compared with traditional USV systems, this invention changes the power source for heading control from underwater to above water, and attitude changes from servo deflection to jet power, eliminating the lag caused by water flow resistance and providing a rapid response capability to change heading. This solves many problems related to USV heading control and crosswind resistance.

Description

Technical Field

[0001] This invention belongs to the field of unmanned surface vessel (USV) heading control and anti-interference technology, specifically relating to an USV system with a rapid maneuvering and anti-interference steering assistance system. Background Technology

[0002] With the rapid development of unmanned technology, unmanned surface vessels (USVs) are being used more and more widely in maritime missions, including complex tasks such as search and rescue, network reconnaissance, and transportation. This has greatly saved manpower costs, reduced safety hazards, and improved work efficiency.

[0003] In modern technology, navigation control is a core technology for unmanned surface vessels (USVs), with heading control and trajectory tracking being the most important. Currently, USV heading control often employs a vector engine control strategy, relying on the deflection of the nozzles of the waterjet propulsion system at the stern to provide power and handle heading control. This places high demands on the engine. Furthermore, because the nozzles constantly experience water resistance during deflection, the turning process is very slow, and the USV is highly insensitive to sudden disturbances such as ocean currents and crosswinds, essentially lacking anti-interference capabilities.

[0004] This method of adjusting heading solely by vectoring engines has the following drawbacks:

[0005] 1. In actual waters, the deflection angle of a vector engine needs to withstand the resistance of the water flow, and it takes a certain amount of time to deflect to the target angle. The efficiency of the engine in executing heading control is low, resulting in a very slow turning process.

[0006] 2. Because the course adjustment process of vector engines is very slow, the control system cannot simultaneously meet the requirements of stable, accurate, and fast control. Pursuing rapid course adjustment will lead to overshoot, which manifests as zigzagging navigation of the unmanned surface vessel and poor trajectory tracking accuracy; conversely, pursuing high trajectory tracking accuracy requires a long time to achieve the desired effect, making it unable to cope with sudden obstacles, lacking maneuverability, and unsuitable for the needs of modern maritime missions.

[0007] 3. Due to the long reaction time of the heading control and the limited reaction capability of the engine, it is not very sensitive to interference and cannot react in time. The function of resisting crosswinds or sudden interference is basically impossible.

[0008] Meanwhile, another technology involves installing drag engines on both sides of the hull. The torque generated by deceleration on one side allows the boat to turn to the desired direction. This method greatly improves the boat's reaction speed, eliminating the need to wait for the slow engine deflection process. However, it still has problems:

[0009] 1. The hulls of unmanned surface vessels (USVs) designed according to their operating environment tend to be long and slender to reduce water resistance. This means that USVs cannot significantly improve their turning performance through lateral torque because the lateral dimensions are insufficient and the lever arm is not long enough.

[0010] 2. Due to the small lateral dimensions of the unmanned surface vessel, only a small portion of the drag generated by the engines mounted on both sides contributes to turning. To a greater extent, it offsets the thrust of the main engine at the stern, causing the vessel to decelerate as a whole. The greater this force, the slower the vessel's speed, making it impossible to simultaneously ensure normal navigation and turning.

[0011] 3. This method requires adding a drag engine to each side of the boat's edge. Regardless of the type of engine used, the entire system requires three engines, which greatly increases the boat's weight and makes it unsuitable for small unmanned surface vessels.

[0012] These shortcomings ultimately stem from the fact that traditional unmanned surface vessels (USVs) rely on vectoring engines to deflect nozzles and change thrust direction to alter their course. This process encounters strong water resistance, resulting in very slow course changes. Furthermore, balancing speed and stability in the control system is difficult. Due to the reaction delay caused by water resistance, if the control system outputs a large control quantity to achieve rapid turns, it will produce overshoot and prolonged oscillations, leading to continuous zigzagging and even divergence causing system failure. Conversely, if the control system outputs a small adjustment quantity to achieve smooth turns, it must sacrifice speed, resulting in very long adjustment times. Finally, due to the system's slow response, its sensitivity is essentially inadequate against crosswinds. Summary of the Invention

[0013] This invention provides an unmanned surface vessel (USV) with a rapid maneuvering and anti-interference steering assist system, which solves the problems of slow maneuvering response, limited execution power, poor turning performance, and poor crosswind resistance of traditional USVs.

[0014] This invention is achieved through the following technical solutions:

[0015] An unmanned surface vessel system with a rapid maneuvering and anti-interference steering assistance system includes a ground station and an unmanned surface vessel. The unmanned surface vessel includes a shipborne radio, sensors, a navigation control system, a control distributor, and actuators.

[0016] The sensors include inertial navigation sensors and wind speed and direction indicators; the navigation control system includes a heading control system and an anti-interference control system; the anti-interference control system includes a crosswind controller; the factors controlled by the anti-interference control system include lateral deviation, lateral velocity, and roll angle; the sensors transmit data including hull attitude and environmental information to the navigation control system;

[0017] The actuators include a steering assist system consisting of an engine turntable and a jet engine, and a water jet propulsion system. The jet engine is mounted on the engine turntable and rotates with it. The engine turntable is mounted on the mast of the unmanned surface vessel.

[0018] Navigation instructions, routes, and control commands are issued by the ground station, transmitted to the ship's radio station, and then parsed by the ship's navigation control system. The maneuvering inputs are then sent to the respective execution systems via the control distributor, and the execution systems act accordingly.

[0019] The steering assist system includes two system data interfaces: 1) the turntable manipulation amount ΔΨ, representing the angle the engine turntable needs to turn in the heading direction. a ,ΔΨ a The signal is sent from the navigation control system to the engine turntable, and its signal cable is connected to the onboard control terminal, which in turn connects the cable to the onboard electrical equipment; 2) ΔT represents the amount of adjustment required for jet engine power. a ΔT a The signal is sent from the navigation control system to the jet engine, and its signal cable is connected to the onboard control terminal, which in turn connects to the onboard electrical equipment.

[0020] The smaller portion of the total control input output by the navigation control system is handled by the steering assist system, which is responsible for anti-interference work throughout the navigation process. When the lateral aerodynamic forces are sufficient for the mission requirements, the heading adjustment is entirely completed by the steering assist equipment, and the waterjet propulsion only provides forward propulsion without deflecting its nozzle. When the unmanned surface vessel (USV) needs to perform maneuvers such as sharp turns, maneuvering, or emergency obstacle avoidance, the waterjet propulsion system is insufficient to move the hull for large maneuvers. In this case, the navigation control system controls the nozzle deflection of the waterjet engine at the tail of the waterjet propulsion system to compensate for the lateral forces. When the heading does not need to be changed, the navigation control system controls the jet engine turntable to align the aerodynamic forces with the USV's forward direction, further increasing the USV's speed.

[0021] When the unmanned surface vessel is disturbed by ocean currents or crosswinds, the crosswind controller calculates a lateral force including its magnitude and direction, controls the engine turntable to turn to the corresponding angle, and the jet engine outputs a lateral force in the opposite direction to the crosswind, gradually eliminating the roll of the hull caused by the crosswind and returning to the course.

[0022] The control law expression for the crosswind controller is:

[0023]

[0024]

[0025]

[0026] The controller introduces lateral velocity deviation. Lateral deviation (YY) g ), Roll deviation (Φ-Φ g The roll rate p is used as a control input. This is the proportional coefficient corresponding to the roll rate term; This is the proportional coefficient corresponding to the roll deviation; This is the proportional coefficient corresponding to the lateral velocity deviation term; The coefficient of the integral element corresponding to the lateral velocity term; This is the proportional coefficient corresponding to the lateral deviation term.

[0027] The ground station can switch between navigation control modes, which are manual and automatic. The control panel can be modified and the necessary equipment can be added according to the control mode.

[0028] In automatic mode, the control system directly sends route or mission information, without the need for physical buttons. Simply connect the data cables of the jet engine and the engine turntable to the onboard control terminal.

[0029] In manual mode, the direction of the engine turntable is controlled by a joystick, requiring the addition of a control joystick or handle to the control panel; the engine power is controlled by a push-pull lever or knob, requiring the addition of a similar device to the control panel; at the same time, the data cables of the jet engine and the engine turntable are connected to the onboard control terminal.

[0030] Compared with traditional unmanned surface vessel (USV) systems, this invention changes the power source for heading control from underwater to above water, and changes attitude from servo deflection to jet power. This eliminates the lag caused by water resistance and provides the ability to quickly change course, breaking the fundamental contradiction in the heading control problem of USVs and solving many problems such as heading control and crosswind resistance. Attached Figure Description

[0031] Figure 1 This is a structural diagram of the steering assist system of the present invention;

[0032] Figure 2 This is a block diagram of the system components of the present invention;

[0033] Figure 3 This is a structural diagram of the crosswind controller of the present invention;

[0034] Figure 4 This is a flowchart of the workflow of the present invention. Detailed Implementation

[0035] This invention provides a modification scheme that, by adding a jet engine and a simple engine turntable to the mast, provides aerodynamic thrust to the hull in all directions, transferring steering power from underwater to above water and overcoming the effects of water flow resistance. The turntable can adjust to the target angle within milliseconds, rapidly changing the direction of steering power; the jet engine's power adjustment time is also extremely short. This combined device can quickly change the direction and magnitude of steering power on the hull side. Based on this, this invention, using a novel unmanned surface vessel platform with the added equipment, develops a control allocation strategy to maximize the efficiency of both power systems.

[0036] Meanwhile, due to the rapid response of the added equipment, it is highly sensitive to minor disturbances and possesses a rapid reaction capability to interference from ocean currents and crosswinds. Therefore, this invention, based on the steering assist system, designs a real-time anti-interference control strategy for the unmanned surface vessel platform.

[0037] The main idea of ​​this invention is to design a rapid steering assistance system for unmanned surface vessel (USV) platforms, and to design control allocation strategies and anti-interference control strategies for them, so that USVs have rapid maneuverability and anti-interference capabilities.

[0038] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0039] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the design of the unmanned surface vessel system with rapid maneuverability and anti-interference steering assistance system proposed in this invention includes the following steps:

[0040] Step 1: Design and installation of steering assistance equipment

[0041] The steering assist system designed in this invention is installed on the mast of the unmanned surface vessel, and its composition and installation method are as follows: Figure 1 As shown, it is divided into two parts:

[0042] 1. Jet engine: Provides the aerodynamic force required for steering and can quickly adjust the power output. The engine itself does not have steering ability; to compensate for this, it is mounted on a turntable and rotates with the turntable.

[0043] 2. Engine Turntable: Drives the jet engine to the target angle according to commands from the host computer. The turntable is mounted on the mast of the unmanned surface vessel (USV), and the jet engine is mounted on it, driving the engine to rotate. The turntable is highly sensitive, with a turning time in the millisecond range.

[0044] Step 2: Ground station control console modification

[0045] The ground station can switch between navigation control modes, which are manual and automatic. The control panel can be modified and the necessary equipment can be added according to the control mode.

[0046] In automatic mode, the control system directly sends route or mission information, eliminating the need for physical buttons. Simply connect the data cables of the engine and turntable to the onboard control terminal.

[0047] In manual mode, the direction of the engine turntable is controlled by a joystick, requiring the addition of a control joystick or handle to the control panel; engine power is controlled by a push-pull lever or knob, requiring the addition of a similar device to the control panel. Simultaneously, connect the data cables for both the engine and the turntable to the onboard control terminal.

[0048] Step 3: System Interface Connection

[0049] The unmanned surface vessel (USV) system consists of two parts: a ground station and the USV itself. Navigation commands, routes, and control orders are issued by the ground station and transmitted to the onboard radio. After being analyzed by the onboard control system, the control signals are sent to the various execution systems, which then act according to the control signals.

[0050] The steering assist system designed in this invention includes two system data interfaces:

[0051] 1. Turntable manipulation amount ΔΨ a This represents the angle (in the heading direction) that the turntable needs to be turned. Let's assume the current turntable heading angle is Ψ. a The command specifies the angle the turntable should reach. Then ΔΨ a It is composed of Ψ a Turn to The intermediate execution amount. ΔΨ a The signal is sent from the control system to the turntable, and its signal cable is connected to the ship's control terminal, which in turn connects to the ship's electrical equipment.

[0052] 2. Jet engine power control quantity ΔT a This represents the amount of engine power that needs to be adjusted. Let's assume the current engine power is T. a The instruction specifies the power that the engine needs to provide. Then ΔT a It is made of T a Adjust to The intermediate control quantity. ΔT a The signal is sent from the control system to the jet engine, and its signal cable is connected to the ship's control terminal, which in turn connects to the ship's electrical equipment.

[0053] Step 4: Develop a control allocation strategy

[0054] After the addition of steering assistance equipment, the boat has two power sources: a waterjet propulsion system and a steering assistance system. The different characteristics of the two power sources determine their different uses.

[0055] The control system calculates the total control quantity required at present based on the instructions from the host computer. Based on the dynamic characteristics of the unmanned surface vessel, the control quantity of this invention is expressed in terms of force and torque (ΔF, ΔC).

[0056] 1. Waterjet propulsion: The force and torque provided are represented by (ΔF1, ΔC1). It is characterized by providing large power and steering torque, but has a large delay in directional control and is not sensitive to small disturbances. Therefore, it mainly provides forward propulsion and supplements torque during emergency turns.

[0057] 2. Steering Assist System: The forces and torques provided are represented by (ΔF2, ΔC2). Its characteristics include the ability to provide rapidly changing lateral aerodynamic forces, with quick adjustment of the direction and magnitude of the force. It is highly responsive and sensitive to disturbances, able to quickly counteract them. However, its power ceiling is relatively small; when a large torque is required for a significant change in the heading of the ladder stop, a water jet engine is still needed to assist in deflection.

[0058] Considering the characteristics of the two power systems and taking into account the application scenarios of the unmanned surface vessel platform, this invention proposes the following control allocation strategy:

[0059] First, since waterjet propulsion is not sensitive to interference, a small portion of the total control output is handled by the steering assist system, which is responsible for anti-interference work throughout the entire navigation process.

[0060] Secondly, when the lateral aerodynamic force can meet the mission requirements, the heading adjustment is completed entirely by the steering assist equipment, and the waterjet propulsion only provides forward propulsion, and its nozzle does not deflect. When the unmanned surface vessel needs to make sharp turns, maneuver, or perform emergency obstacle avoidance and other actions that require rapid changes in heading, the jet propulsion equipment is insufficient to mobilize the large hull to perform large maneuvers. At this time, the control system will control the nozzle of the tail waterjet engine to deflect to compensate for the lateral force.

[0061] Finally, when the course does not need to be changed, the jet engine turntable can be controlled to align the aerodynamic forces with the unmanned surface vessel's (USV) direction of travel, further increasing the USV's speed. This fully utilizes the turntable's rotational capability and the efficiency of the dual-power system.

[0062] Step 5: Design an anti-interference controller

[0063] Unmanned surface vessel (USV) platforms equipped with steering assistance systems possess disturbance resistance capabilities. The main disturbances during USV navigation include crosswinds and ocean currents, both of which can alter the vessel's attitude and affect trajectory accuracy. This invention transmits data from onboard sensors (primarily inertial navigation and anemometers) to the control system, and designs a corresponding controller based on the vessel's attitude and environmental information.

[0064] When an unmanned surface vessel (USV) is disturbed by ocean currents or crosswinds, the hull will deviate laterally and its attitude will change. At this time, the crosswind controller will calculate a lateral force (including magnitude and direction) and control the jet engine and its turntable to turn to the corresponding angle. The jet engine outputs a lateral force in the opposite direction to the crosswind, gradually eliminating the roll of the hull caused by the crosswind and returning it to the course.

[0065] Controller structure as follows Figure 3 As shown. The corresponding control law expression is:

[0066]

[0067]

[0068]

[0069] The controller introduces lateral velocity deviation. Lateral deviation (YY) g ), Roll deviation (Φ-Φ g The roll rate p is used as a control input. This is the proportional coefficient corresponding to the roll rate term; This is the proportional coefficient corresponding to the roll deviation; This is the proportional coefficient corresponding to the lateral velocity deviation term; The coefficient of the integral element corresponding to the lateral velocity term; This is the proportional coefficient corresponding to the lateral deviation term.

[0070] Compared to traditional anti-interference control systems, this system incorporates lateral deviation, lateral velocity, and roll angle into the feedback network. Through layer-by-layer error elimination, the lateral parameters are brought back to normal. It comprehensively considers the factors affecting the hull's lateral attitude, resulting in better control performance.

[0071] Step Six: Overall Workflow

[0072] Steps one through five describe the composition, structure, working principle, and design concept of the steering assist system. Step six will explain the actual operating process of the system, as follows: Figure 4 As shown.

[0073] Step 1. Receiving Ground Station Commands: During fully automated navigation, the ground station will pre-program the mission route, which for the unmanned surface vessel (USV) is a set of latitude and longitude coordinates {(X0,Y0),(X1,Y1),…,(X...}. n ,Y n The unmanned surface vessel only needs to focus on its current position (x). now ,y now ) and the location of the next waypoint (X) next ,Y next );

[0074] Step 2. Command Analysis: Based on the ground station commands, calculate the unmanned surface vessel's (USV) mission heading. For the USV, the target's absolute position is meaningless; it needs to be calculated as its current position (x, y). now ,y now ) to the next waypoint (X) next ,Y next ) target heading H g This allows the unmanned surface vessel to navigate along the target course.

[0075] Step 3. Control System Calculates Maneuvering Variables: Target heading, environmental information, and attitude information are input into the control system. The control system, combining mission requirements and comprehensive information, calculates the maneuvering variables for the execution systems in real time. This includes the heading control system and the crosswind control system.

[0076] Step 4. Control Allocation: Distribute the control input to the two power systems according to the allocation strategy;

[0077] Step 5. Actuator Action: The actuators (water jet propulsion unit, jet engine, and turntable) deflect at the corresponding angle and adjust the power according to the assigned manipulation amount;

[0078] Step 6. Mission Objective Verification: If the target course has been reached in the current cycle, continue sailing along this route, i.e., set the control input to zero; if the target course has not been reached in the current cycle, return to Step 2 and update H in real time. g Then proceed with the calculation for the next cycle, repeating this process until the target course is reached.

[0079] The beneficial effects of this invention are:

[0080] In addressing traditional problems:

[0081] 1. This invention enables unmanned surface vessels to quickly change course and maintain stable navigation after turning, avoiding lengthy adjustment processes and the problem of meandering navigation after turning. It achieves the control requirements of stability, accuracy, and speed, resulting in a smoother trajectory and higher control precision.

[0082] 2. The system's responsiveness meets the requirements for crosswind resistance. This invention simultaneously designs a real-time crosswind resistance control system, which is sufficient to cope with stable or continuously changing winds such as gusts and crosswinds.

[0083] Regarding future development:

[0084] 1. This invention greatly improves the maneuverability of unmanned surface vessels, enabling them to perform difficult turns and maneuvers, and can be applied to more scenarios and cope with harsher environments. It can perform difficult turns and U-turns at any time.

[0085] 2. The steering assist system added to this invention can be used for multiple purposes as needed. In addition to heading control and crosswind resistance, it can also be linked with the main engine to act as a secondary engine, outputting thrust in the same direction to further increase the speed of the unmanned surface vessel. Simultaneously, it can also output force in the opposite direction to help the unmanned surface vessel brake quickly, which is very helpful in responding to sudden threats at sea.

[0086] This invention solves the fundamental contradiction in the heading control of unmanned surface vessels by adding a steering assist system, which transfers steering power to the water surface and eliminates water flow resistance. It not only satisfies both speed and stability, but also overcomes the problems of resisting crosswinds and ocean current interference.

Claims

1. An unmanned surface vessel (USV) system with a rapid maneuvering and anti-interference steering assist system, comprising a ground station and an USV, characterized in that: Unmanned surface vessels (USVs) include shipborne radios, sensors, navigation control systems, control distributors, and actuators. The sensors include inertial navigation sensors and wind speed and direction indicators; the navigation control system includes a heading control system and an anti-interference control system; the anti-interference control system includes a crosswind controller; the factors controlled by the anti-interference control system include lateral deviation, lateral velocity, and roll angle; the sensors transmit data including hull attitude and environmental information to the navigation control system; The actuators include a steering assist system consisting of an engine turntable and a jet engine, and a water jet propulsion system. The jet engine is mounted on the engine turntable and rotates with it. The engine turntable is mounted on the mast of the unmanned surface vessel. Navigation instructions, routes, and control commands are issued by the ground station, transmitted to the ship's radio station, and then parsed by the ship's navigation control system. The maneuvering inputs are then sent to the respective execution systems via the control distributor, and the execution systems act accordingly. The steering assist system includes two system data interfaces: 1) the turntable manipulation amount ΔΨ, representing the angle the engine turntable needs to turn in the heading direction. a ,ΔΨ a The signal is sent from the navigation control system to the engine turntable, and its signal cable is connected to the onboard control terminal, which in turn connects the cable to the onboard electrical equipment; 2) ΔT represents the amount of adjustment required for jet engine power. a ΔT a The signal is sent from the navigation control system to the jet engine, and its signal cable is connected to the onboard control terminal, which in turn connects to the onboard electrical equipment. The smaller portion of the total control input output by the navigation control system is handled by the steering assist system, which is responsible for anti-interference work throughout the navigation process. When the lateral aerodynamic forces are sufficient for the mission requirements, the heading adjustment is entirely completed by the steering assist equipment, and the waterjet propulsion only provides forward propulsion without deflecting its nozzle. When the unmanned surface vessel (USV) needs to perform maneuvers such as sharp turns, maneuvering, or emergency obstacle avoidance, the waterjet propulsion system is insufficient to move the hull for large maneuvers. In this case, the navigation control system controls the nozzle deflection of the waterjet engine at the tail of the waterjet propulsion system to compensate for the lateral forces. When the heading does not need to be changed, the navigation control system controls the jet engine turntable to align the aerodynamic forces with the USV's forward direction, further increasing the USV's speed. When the unmanned surface vessel is disturbed by ocean currents or crosswinds, the crosswind controller calculates a lateral force including its magnitude and direction, controls the engine turntable to turn to the corresponding angle, and the jet engine outputs a lateral force in the opposite direction to the crosswind, gradually eliminating the roll of the hull caused by the crosswind and returning to the course.

2. The crosswind controller according to claim 1, characterized in that: The corresponding control law expression is: The controller introduces lateral velocity deviation. Lateral deviation (YY) g ), Roll deviation (Φ-Φ g The roll rate p is used as a control input. This is the proportional coefficient corresponding to the roll rate term; This is the proportional coefficient corresponding to the roll deviation; This is the proportional coefficient corresponding to the lateral velocity deviation term; The coefficient of the integral element corresponding to the lateral velocity term; This is the proportional coefficient corresponding to the lateral deviation term.

3. The crosswind controller according to claim 1, characterized in that: The ground station can switch between navigation control modes, which are manual and automatic. The control panel can be modified and the necessary equipment can be added according to the control mode. In automatic mode, the control system directly sends route or mission information, without the need for physical buttons. Simply connect the data cables of the jet engine and the engine turntable to the onboard control terminal. In manual mode, the direction of the engine turntable is controlled by a joystick, requiring the addition of a control joystick or handle to the control panel; the engine power is controlled by a push-pull lever or knob, requiring the addition of a similar device to the control panel; at the same time, the data cables of the jet engine and the engine turntable are connected to the onboard control terminal.

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