Amphibious vehicle searchlight guided navigation control method and device and amphibious vehicle

Abstract

The application relates to the technical field of vehicle control, and discloses an amphibious vehicle searchlight guiding navigation control method and device and an amphibious vehicle. The method comprises the following steps: target vector information output after a searchlight locks a target is acquired, the target vector information at least comprising an azimuth angle of the target relative to a vehicle body; a navigation control instruction is generated based on the target vector information and current vehicle state information; the navigation control instruction is sent to a corresponding actuator, and the searchlight is controlled to continuously track the target, so that a closed-loop cooperative control is formed. The searchlight is upgraded from an illuminating device to a navigation guiding sensor, water power lag is offset through feedforward compensation, and precise target tracking and navigation control of the amphibious vehicle under night or low-visibility conditions can be realized.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a method, device and amphibious vehicle for navigation control with searchlight guidance. Background Technology

[0002] Amphibious vehicles, as special vehicles capable of both land and water travel, rely on existing technologies to accurately determine the location and distance of targets when navigating at night or in low visibility conditions. These technologies typically involve mounting a searchlight with a gimbal servo system. After locking onto a target through image processing or manual operation, the searchlight automatically follows the target, keeping its beam continuously aligned. However, in this approach, the tracking angle information (azimuth and pitch angles) from the searchlight gimbal is only used to drive the gimbal servo motor; the driver still needs to visually observe the position of the beam to determine the accuracy of the heading. Summary of the Invention

[0003] Embodiments of this application provide a method, device, and amphibious vehicle for searchlight-guided navigation control of an amphibious vehicle, so as to achieve real-time heading control based on the searchlight attitude.

[0004] A navigation control method for an amphibious vehicle guided by a searchlight includes: acquiring target vector information output by the searchlight after locking onto a target, the target vector information including at least the azimuth angle of the target relative to the vehicle body; generating a navigation control command based on the target vector information and current vehicle status information; sending the navigation control command to the corresponding actuator and controlling the searchlight to continuously track the target, forming a closed-loop cooperative control.

[0005] In some embodiments, before obtaining the target vector information output after the searchlight locks onto the target, the method further includes: receiving a target locking command input by the driver, or receiving a target selection command on the touchscreen, and controlling the searchlight to align with and lock onto the target.

[0006] In some embodiments, the current vehicle status information includes at least one of the following: current speed, vehicle roll angle, driving mode, and vehicle attitude angle.

[0007] In some embodiments, the generation of the thruster differential command adopts a proportional-derivative control law, wherein the control command is composed of the superposition of the proportional term of the azimuth deviation and the derivative term of the azimuth rate of change; the proportional coefficient and the derivative coefficient are both determined by looking up a table according to the current speed.

[0008] In some embodiments, the target vector information also includes an estimated distance; the estimated distance is calculated based on the searchlight's installation height, pitch angle, vehicle pitch angle, and vehicle draft, using trigonometric relationships.

[0009] In some embodiments, the generation of navigation control commands also includes: sending the expected vehicle body turning angular velocity to the searchlight subsystem, so that the searchlight subsystem can superimpose a compensation amount opposite to the vehicle body turning direction on the gimbal azimuth angle command. The compensation amount is determined by the product of the expected vehicle body turning angular velocity and the control period, and the direction is opposite to the vehicle body turning direction.

[0010] In some embodiments, after the navigation control command is generated, the method further includes: limiting the navigation control command, including at least one of thruster differential speed limiting and command rate of change limiting.

[0011] In some embodiments, the process of controlling the searchlight to continuously track the target further includes: monitoring the validity of the target vector information; when no valid target vector information is received for several consecutive control cycles, or when the target azimuth angle exceeds the physical rotation range of the searchlight, the target is determined to be lost, and a degradation strategy is initiated.

[0012] In some embodiments, in response to the need for amphibious vehicles to land, the direction of the dock is determined; based on the slope set at the dock, the slope is extended underwater to delineate a strip-shaped navigation area; a series of virtual target points are selected along the slope normal; virtual targets in the virtual target sequence are selected from near to far as the current tracking target, and navigation control is performed for the current tracking target; when the horizontal distance between the vehicle and the current virtual target is less than a set threshold, the vehicle switches to the next more distant virtual target as the new current tracking target.

[0013] A second aspect of the present invention provides a searchlight-guided navigation control device for an amphibious vehicle, comprising: an acquisition module configured to acquire target vector information output after the searchlight locks onto a target, the target vector information including at least the azimuth angle of the target relative to the vehicle body; a generation module configured to generate navigation control commands based on the target vector information and current vehicle state information; and a control module configured to send the navigation control commands to a corresponding actuator and control the searchlight to continuously track the target, forming a closed-loop cooperative control.

[0014] A third aspect of the present invention provides an amphibious vehicle, comprising: a memory for storing a computer program; and a processor for executing the computer program to implement the method.

[0015] Compared to existing technologies where searchlights are merely used as lighting devices and target angle information is limited to servo control within the gimbal, the above one or more technical solutions use the target azimuth angle of the searchlight gimbal as the heading deviation input of the navigation control system. They utilize the high-frequency angle feedback of the searchlight to replace the traditional heading sensor, and compensate for the lag in amphibious vehicle water handling through thruster differential speed compensation. This significantly reduces the driver's nighttime operating burden, shortens the target tracking response time, and improves the safety and accuracy of amphibious vehicle navigation in low-visibility environments. Attached Figure Description

[0016] The above and other features, advantages, and aspects of the embodiments of this application will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein: Figure 1 A schematic diagram of an example environment in which various embodiments of the present invention can be implemented is shown; Figure 2 A flowchart is shown for a navigation control method for an amphibious vehicle guided by a searchlight, according to some embodiments of the present invention. Figure 3 A schematic diagram illustrating the calculation of the horizontal distance between the searchlight and the target is shown in some embodiments according to the present invention; Figure 4 A schematic diagram illustrating the calculation of the horizontal distance between the searchlight and the target is shown in some other embodiments according to the present invention; Figure 5 A flowchart of a navigation control method for an amphibious vehicle landing scenario according to some embodiments of the present invention is shown; Figure 6 A program module architecture diagram of a searchlight-guided navigation control device for an amphibious vehicle according to some embodiments of the present invention is shown. Detailed Implementation

[0017] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While some embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this application. It should be understood that the drawings and embodiments of this application are for illustrative purposes only and are not intended to limit the scope of protection of this application.

[0018] In the description of embodiments of this application, the term "comprising" and similar terms should be understood as open-ended inclusion, i.e., "including but not limited to". The term "based on" should be understood as "at least partially based on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0019] Figure 1 A schematic diagram of an example environment 100 in which various embodiments of the present invention can be implemented is shown. For example... Figure 1 As shown, the example environment 100 includes an amphibious vehicle 110, a searchlight subsystem 120, a domain controller 130, and an actuator layer 140.

[0020] The amphibious vehicle 110 is a special vehicle capable of both land and water travel. It is equipped with a searchlight subsystem 120 on its roof, a domain controller 130 inside the vehicle, and dual thrusters at the rear. The amphibious vehicle 110 can also be expanded into unmanned surface vessels, amphibious unmanned platforms, and other forms.

[0021] The searchlight subsystem 120 includes a searchlight body, a servo motor with an absolute encoder, and an inertial measurement unit for locking onto a target and outputting target vector information and vehicle attitude angles. The searchlight subsystem 120 can also be expanded into a composite sensor module equipped with a camera.

[0022] Domain controller 130 is an on-board central computing unit, which can also be expanded into an edge computing node. Domain controller 130 receives target vector information and sensor data output by searchlight subsystem 120 through communication bus, executes the cooperative control algorithm of the present invention, outputs thruster differential speed command at a fixed control cycle, and sends it to actuator layer 140.

[0023] The actuator layer 140 includes dual thrusters, which receive and execute thruster differential commands output from the domain controller 130. The searchlight subsystem 120 communicates with the domain controller 130 via a communication bus or via an in-vehicle Ethernet network.

[0024] The data collection and processing in this embodiment strictly comply with relevant laws and regulations. Data collection such as vehicle position and attitude requires authorization and is used solely for navigation control, not for any other unauthorized purposes. It should be understood that the example environment 100 is described for illustrative purposes only and does not imply any limitation on the scope of the invention. The invention can also be applied to other scenarios such as maritime search and rescue, maritime patrol, and port guidance. The environment may also include components such as sensors and communication modules (not shown).

[0025] Figure 2A flowchart of a searchlight-guided navigation control method 200 for an amphibious vehicle according to some embodiments of the present invention is shown. This method 200 can be, for example, by... Figure 1 The domain controller 130 shown executes this. It should be understood that method 200 may also include additional actions not shown, and the scope of the invention is not limited in this respect. The following is in conjunction with... Figure 1 Example environment 100 is used to describe method 200 in detail.

[0026] In box 210, target vector information output after the searchlight locks onto the target is acquired. For example, domain controller 130 can receive target vector information output by searchlight subsystem 120, the target vector information including at least the azimuth angle of the target relative to the vehicle body.

[0027] It should be understood that the "target" in this application is not limited to a specific object type. Any object on the water surface or shore that a driver needs to continuously track, approach, or avoid can be considered a target as described in this application. For example, a target can be other vessels, speedboats, or surface buoys that need to be followed or approached; a target can also be a person who has fallen into the water or a floating rescue object that needs to be continuously located in a maritime search and rescue scenario; a target can also be a lighthouse, buoy, or shoreline reference used to guide navigation in a port guidance scenario; and a target can also be a surface target that needs to be monitored in a maritime patrol scenario. It should be understood that the above examples are for illustrative purposes only and are not intended to limit the types of targets. The scope of protection of this application is not limited to specific categories of targets.

[0028] In some embodiments, before acquiring target vector information, the domain controller 130 can receive a target locking command input by the driver or a target selection command on the touchscreen, and control the searchlight to aim at and lock onto the target. For example, the driver can manipulate the searchlight control lever to align the center spot of the light with the target and then press the lock button, and the searchlight enters automatic tracking mode. Alternatively, the driver can select a target area on the touchscreen, and the searchlight automatically adjusts to the center of that target area and locks onto it, entering automatic tracking mode. After the driver presses the lock button or completes the touchscreen selection, the searchlight subsystem 120 determines that the pixel deviation of the target in several consecutive frames is below a set threshold. If the target is successfully locked, it switches to automatic tracking mode and begins outputting target vector information to the domain controller 130; if the locking fails, the driver is prompted to try again.

[0029] In some embodiments, after the searchlight enters automatic tracking mode, the searchlight subsystem 120 continuously identifies the target using its onboard camera, acquiring the pixel deviation of the target in the image, i.e., the horizontal and vertical deviation of the target from the center of the light spot. Using the pixel deviation as an error signal, it drives a servo motor with an absolute encoder to adjust the azimuth and pitch angles of the gimbal, ensuring that the center of the searchlight spot remains aligned with the target. The searchlight subsystem 120 has a built-in inertial measurement unit that measures the vehicle's attitude angles in real time, including pitch angle α and roll angle γ, to provide feedforward compensation for servo control commands and eliminate the impact of vehicle sway on tracking accuracy. The absolute encoder of the gimbal servo motor outputs the azimuth angle θ and pitch angle φ of the gimbal relative to the vehicle in real time. Combined with the vehicle attitude angles output by the inertial measurement unit, these constitute the angular components of the target vector information, which are sent to the domain controller 130 via a communication bus. Thus, the searchlight subsystem 120 integrates traditional lighting functions with target angle measurement functions, continuously outputting accurate target angle information while maintaining the light spot aligned with the target, providing real-time input for the generation of navigation control commands by the domain controller 130.

[0030] In block 220, navigation control commands are generated based on target vector information and current vehicle status information. For example, domain controller 130 can generate navigation control commands based on the target vector information and current vehicle status information, including thruster differential commands.

[0031] In some embodiments, the current vehicle status information includes at least one of current speed, vehicle roll angle, driving mode, and vehicle attitude angle. The current vehicle status information is collected by the domain controller 130 from various sensors. The driving modes include manual driving mode and searchlight tracking automatic mode; when the driving mode is searchlight tracking automatic mode, the domain controller 130 executes the control method described in this embodiment; when the driving mode is manual driving mode, the driver's manual control commands are directly sent to the actuator through the priority arbitration module, and the output of the cooperative control algorithm is masked.

[0032] The purpose of navigation control is to ensure that the searchlight is always pointed at the target while the vehicle's front end is also always pointed at the target, that is, to keep the gimbal azimuth angle θ close to 0. Since the hydrodynamic maneuvering response characteristics of amphibious vehicles change nonlinearly with speed, fixed-parameter PID cannot adapt to the entire speed range. Therefore, in some embodiments, the optimal parameters for each speed range are calibrated offline using a lookup table method.

[0033] The generation of thruster differential commands uses a PD control law, and the general formula is:

[0034] in, This is the thruster differential command, which is the difference in rotational speed between the left and right thrusters. Viewed from above the vehicle body, clockwise is positive and corresponds to turning right, while counterclockwise is negative and corresponds to turning left. This represents the current azimuth deviation, i.e., the horizontal angle by which the target deviates from the direction of the vehicle's front. The azimuth rate of change reflects the speed and trend of deviation changes; This is a proportionality coefficient, varying with speed. Look up values ​​from a table; control command and current deviation Proportional The larger the value, the greater the differential command and the stronger the correction force; These are differential coefficients, varying with speed. Look up values ​​from the table, control commands and rate of change of deviation Proportional to the target direction, when the deviation is decreasing, the front of the vehicle deflects towards the target direction, θ tends to decrease, the derivative term is negative, reducing the amplitude of the propeller differential command (or generating a reverse differential), suppressing the tendency of the vehicle to continue deflecting, and preventing excessive deflection from causing overshoot; when the deviation is increasing, the front of the vehicle deviates from the target direction, θ tends to increase, the derivative term is positive, and the acceleration force in the same direction as the correction is superimposed, prompting the front of the vehicle to return to the target direction as soon as possible.

[0035] For example, generating navigation control commands includes: determining the thruster differential command by looking up a table based on the azimuth angle and the rate of change of azimuth angle, combined with the current speed. In some embodiments, the lookup parameters for the thruster differential command are set in segments according to the speed. At low speeds, vehicle steering relies entirely on the yaw torque generated by the thruster differential, resulting in relatively high hydrostatic resistance. A larger proportional coefficient is needed to drive the vehicle to yaw, and the derivative coefficient should be small to avoid low-speed vibration. At medium speeds, the proportional and derivative coefficients are taken as intermediate values. At high speeds, the yaw response generated by the thruster thrust is more sensitive, and the vehicle inertia is large. If the proportional coefficient is too large, overshoot or even oscillation can easily occur. The derivative coefficient needs to be increased to provide damping to suppress overshoot; therefore, the proportional coefficient is taken as a smaller value, and the derivative coefficient as a larger value. It should be understood that the above parameter values ​​are determined through actual vehicle calibration, and the specific values ​​depend on the thruster model, vehicle hydrodynamic characteristics, and load conditions. The proportional coefficient of the PD control law is obtained by looking up a table based on the current speed. and differential coefficients Then, the propeller differential speed command is calculated by substituting the values ​​into the PD control law formula. Thus, in the low-speed range, the proportional coefficient is increased to overcome hydrostatic resistance, and in the high-speed range, the differential coefficient is increased to suppress directional overshoot, adapting to the hydrodynamic characteristics at different speeds and improving control accuracy.

[0036] It is understandable that when the domain controller 130 issues a heading change command to drive the vehicle to turn, the vehicle rotation will cause a change in the absolute azimuth angle of the searchlight gimbal. If the inner ring of the searchlight relies solely on image feedback for correction, there is a lag of one control cycle. During this period, the light spot may briefly deviate from the target, causing interruption of the target vector information. Therefore, in some embodiments, the domain controller 130, while generating the navigation control command, synchronously sends the expected vehicle turning angular velocity dψ / dt as a feedforward signal to the searchlight subsystem 120. The searchlight subsystem 120 then adds a compensation amount to the gimbal azimuth angle command accordingly.

[0037] The expected steering angular velocity dψ / dt of the vehicle body can be estimated based on the thruster differential command and the vehicle yaw kinematic model: the expected angular velocity is calculated by using the calibrated yaw response coefficient according to the current speed and the thruster differential command; in the embodiment equipped with a gyroscope, the real-time yaw angular velocity measured by the IMU can also be used directly as an approximation. To control the cycle, the vehicle steering command is fed forward to the searchlight gimbal, allowing the gimbal to compensate in advance as the vehicle turns, keeping the spotlight continuously aligned with the target. This maintains the continuity of the inner loop (light aligned with the target) and the outer loop (vehicle aligned with the target) of the dual closed loop, preventing control interruption caused by the spotlight losing the target during vehicle steering.

[0038] In some embodiments, after a navigation control command is generated, the domain controller 130 performs amplitude limiting processing on the navigation control command, including at least one of thruster differential speed limiting and command rate of change limiting, in order to protect the actuator and ensure navigation safety.

[0039] In some embodiments, before sending navigation control commands to the corresponding actuators, the domain controller 130 receives driver manual control commands, searchlight tracking mode automatic commands, and other ADAS function commands, and arbitrates them according to a preset priority, with driver manual control commands having the highest priority, searchlight tracking mode automatic commands second, and other ADAS function commands having the lowest priority. During priority switching, a ramp transition function is used to smooth the control commands, avoiding abrupt actuator changes.

[0040] In box 230, navigation control commands are sent to the corresponding actuators, and the searchlights are controlled to continuously track the target, forming a closed-loop cooperative control. For example, domain controller 130 distributes thruster differential commands to both thrusters to execute the corresponding commands. The searchlights continuously track the target, updating the target vector information in real time. Domain controller 130 receives the updated target vector information at a fixed control cycle and iteratively calculates new control commands, forming a complete closed-loop cooperative control.

[0041] In some embodiments, while controlling the searchlight to continuously track a target, the domain controller 130 monitors the validity of the target vector information. If no valid target vector information is received for several consecutive control cycles, or if the target azimuth angle exceeds the physical rotation range of the searchlight, the target is determined to be lost, and a degradation strategy is initiated.

[0042] In some embodiments, the degradation strategy includes: Level 1 degradation: after the target is lost, for a first predetermined time, the searchlight is controlled to maintain the last known azimuth angle, maintaining the original control trend; Level 2 degradation: after the first predetermined time has passed but before the second predetermined time has passed, the searchlight is controlled to start a sector scan search, and the domain controller switches to inertial navigation mode; Level 3 degradation: after the second predetermined time has passed, the searchlight is controlled to return to the default illumination angle, and the ADAS system is notified to request a switch to navigation mode or driver takeover. Thus, progressive response measures can be taken at different stages of target loss, ensuring a smooth system transition.

[0043] In some embodiments, when a target is recaptured during a sector scan search, the control command smoothly transitions from the current value to the command value corresponding to the new target, avoiding abrupt changes in the actuator.

[0044] Method 200 upgrades the searchlight from a lighting device that "only directs the light toward the target" to a navigation guidance sensor that "directs the vehicle toward the target." The azimuth and pitch angles output in real time when the searchlight gimbal tracks the target serve as direct inputs for the domain controller 130 to generate navigation control commands, driving the thrusters to move and enabling the vehicle to automatically navigate toward the target. This achieves precise target tracking and navigation control at night or in low visibility conditions.

[0045] In some embodiments, the target vector information further includes the horizontal distance of the target relative to the searchlight. This estimated distance is calculated using trigonometric relationships based on the searchlight's installation height, pitch angle, vehicle pitch angle, and vehicle draft. This distance can be used for close-range warning and heading deviation warning. Using the vehicle chassis as a reference plane, the searchlight installation height H is a fixed installation height of the searchlight relative to the chassis, a known constant calibrated at the factory. When the vehicle is navigating on water, let the searchlight installation height relative to the chassis be H, and the chassis submerged depth (i.e., vehicle draft) be d. Then, the effective height of the searchlight above the current water surface is h. eff =Hd.

[0046] like Figure 3 As shown, when the target height is known, such as a water surface target or a reference object of known height, the sum of the searchlight pitch angle and the vehicle pitch angle, φ+α, may be less than zero, equal to zero, or greater than zero. If the target height is known... The formula for calculating the target distance is:

[0047] Where L is the estimated distance, d is the current draft, φ is the searchlight pitch angle, and α is the vehicle pitch angle. When the target is a surface target... The formula for calculating the target distance can be simplified to: .

[0048] It should be understood that when When the value approaches zero, it indicates that the searchlight beam axis is close to horizontal, and the triangulation distance measurement formula is invalid. At this time, you can switch to the two-angle difference method to estimate the distance, or use the distance value of the previous effective cycle to maintain the target distance estimation.

[0049] like Figure 4 As shown, when the target altitude is unknown, such as a land target with uncertain altitude, the sum of the searchlight elevation angle and the vehicle elevation angle, φ+α, may be greater than zero, equal to zero, or less than zero. A two-angle difference method is used to estimate the distance: The vehicle travels in a straight line, and at position P1, the searchlight elevation angle φ1 and the vehicle elevation angle α1 are measured. After traveling a distance ΔS, the vehicle reaches position P2, where the searchlight elevation angle φ2 and the vehicle elevation angle α2 are measured again. Here, φ2+α2>φ1+α1 (the elevation angle increases as the vehicle approaches the target). The vehicle travel distance ΔS can be obtained through onboard odometer or thruster speed integration, or, in GNSS-equipped embodiments, through positioning data differential. Based on the simultaneous equations of the trigonometric relationships at the two positions, the current estimated distance from P2 to the target is:

[0050] The estimated height of the target relative to the water surface is:

[0051] It should be understood that the dual-angle difference method does not require prior information about the target height; it can simultaneously estimate the target distance and height using only the change in pitch angle during vehicle movement. This method is suitable for land target tracking scenarios such as guiding amphibious vehicles ashore. The draft in the above formula refers to the vertical depth of the vehicle submerged at the point where the vertical line directly below the searchlight's installation position intersects the water surface, i.e., the local draft d at the vertical foot of the searchlight. When the vehicle has pitch angle α and roll angle γ, the effective vertical height of the searchlight above the water surface should be corrected to: h eff =H·cos(α)·cos(γ)- d, where H is the fixed installation height of the searchlight relative to the chassis, and d is the local draft at the foot of the searchlight.

[0052] In some embodiments, a pressure sensor is installed underwater on the side wall of the vehicle body to measure the water pressure at the installation point in real time, and the local immersion depth d is obtained by converting water pressure to depth. sensor d sensor=P / (ρ·g), where P is the water pressure, ρ is the density of water, and g is the acceleration due to gravity. This is calculated geometrically by combining the longitudinal and lateral offsets of the sensor's installation position relative to the vertical foot of the searchlight, as well as the vehicle's pitch and roll angles measured by the IMU. In calm water or scenarios where ranging accuracy is not critical, d can also be approximated by the calibrated value of the rated draft in still water, obtained from factory calibration. It should be understood that the estimation method can be flexibly selected based on the vehicle's sensor configuration and accuracy requirements.

[0053] Domain controller 130 can preset judgment rules according to target type: when the target is identified as a water target, the trigonometric ranging formula with known height is used by default; when the target is a land target or the target height exceeds the preset range, it automatically switches to the two-angle difference method; during the switching, the vehicle is required to maintain a basically straight line and the heading deviation does not exceed the set threshold.

[0054] By using the gimbal azimuth angle to reflect the current deviation and the azimuth angle change rate to reflect the deviation trend, differential damping can be used to prevent heading overshoot. Simultaneously, by monitoring the lateral displacement deviation of the vehicle relative to the ideal route of "vehicle front facing the target" using distance L and azimuth angle θ, the vehicle's front is always aligned with the target. Furthermore, since this scheme uses the searchlight azimuth angle θ as a real-time feedback signal, when external disturbances such as water flow and waves cause the vehicle to yaw, the azimuth angle θ increases accordingly. The control law automatically increases the thruster differential speed to correct the yaw, eliminating the need for additional water flow direction measurement. The closed-loop structure is robust to conventional water flow disturbances.

[0055] In some embodiments, the estimated distance is applied to near-field warning. When the estimated distance L is less than a safety threshold, such as 5m, the system initiates a near-field safety warning.

[0056] In some embodiments, the estimated distance is also applied to lateral deviation early warning. Lateral deviation ,when When the set threshold is exceeded, an alarm is triggered to the driver, indicating that the vehicle has deviated too far from its designated position.

[0057] Based on the above method 200, some embodiments of the present invention also provide a method 300 for guiding amphibious vehicle landing at a dock, namely, tracking the dock target, controlling the vehicle to approach the dock ramp from the water surface and complete the landing. For example, as... Figure 5 As shown, method 300 includes the following steps: In box 310, the dock orientation is determined. The searchlight subsystem 120 determines the dock orientation angle in the following ways: (1) The visual algorithm directly extracts the edge of the dock above water and outputs the dock orientation angle; (2) The driver marks the two ends of the dock's front edge on the touch screen, and the searchlight locks the two ends in sequence and outputs the azimuth and distance. The domain controller 130 directly calculates the dock orientation angle based on the coordinates of the two ends. The dock slope extends vertically into the water along the dock's front edge. Therefore, the slope normal, which is the direction the vehicle expects to approach, is the normal of the dock orientation.

[0058] In frame 320, the extended navigation area is defined. Domain controller 130, based on the location of the intersection of the dock's waterline and the water surface and the set slope, extrapolates a safe distance underwater to obtain the endpoint of the extended slope. Using the slope normal as the centerline and the vehicle width plus a safety margin as the bandwidth, a strip-shaped navigation area is defined as a safe corridor for vehicles to disembark.

[0059] In box 330, a virtual target sequence is generated. Domain controller 130 selects a series of virtual target points from near to far along the extended slope line as a substitute target sequence for searchlight tracking. The azimuth angle of each virtual target point is calculated in real time based on the relative relationship between the vehicle's current position and the slope normal, ensuring that the vehicle's heading always approaches the normal of the dock's orientation rather than directly aligning with the dock's feature points, thus avoiding lateral collisions with the dock structure.

[0060] In box 340, virtual targets in the virtual target sequence are selected as the current tracking targets from near to far. For the current tracking target, method 200 is executed to obtain the target vector information output after the searchlight locks onto the target. Based on the target vector information and the current vehicle status information, navigation control commands are generated. Domain controller 130 sequentially selects each point in the virtual target sequence as the current tracking target, drives the searchlight to lock onto the virtual target and outputs the azimuth and distance. Based on the speed lookup table PD control law described in method 200, a thruster differential speed command is generated, causing the vehicle to gradually approach the dock along the slope normal. When the horizontal distance between the vehicle and the current virtual target is less than a set threshold, the system switches to the next, more distant virtual target as the new current tracking target. Thus, without direct steering, the course is progressively corrected by switching points one by one, allowing the vehicle to gradually approach the dock from far to near along the slope normal.

[0061] When the vehicle enters the water-land transition area, it switches to water-land mode until it successfully disembarks. Method 300 then generates a virtual navigation corridor by deriving the slope normal, and uses searchlights to guide the vehicle from the water surface along the slope normal, gradually approaching and disembarking from a distance.

[0062] Corresponding to the above embodiments of the amphibious vehicle searchlight-guided navigation control method, the present invention also provides an amphibious vehicle searchlight-guided navigation control device 400, such as... Figure 6As shown, the device includes: an acquisition module 410, configured to acquire target vector information output after the searchlight locks onto a target, the target vector information including at least the azimuth angle of the target relative to the vehicle body; a generation module 420, configured to generate navigation control commands based on the target vector information and current vehicle status information; and a control module 430, configured to send the navigation control commands to the corresponding actuators and control the searchlight to continuously track the target, forming a closed-loop cooperative control.

[0063] In some embodiments, before the acquisition module 410 acquires the target vector information output after the searchlight locks onto the target, it further includes: receiving a target locking command input by the driver, or receiving a target selection command on the touch screen, and controlling the searchlight to align with and lock onto the target.

[0064] In some embodiments, the acquisition module 410 also acquires current vehicle status information, which includes at least one of current speed, vehicle roll angle, driving mode, and vehicle attitude angle.

[0065] In some embodiments, in the generation module 420, the generation of the thruster differential command adopts a proportional-derivative control law, wherein the control command is composed of the superposition of the proportional term of the azimuth deviation and the derivative term of the azimuth change rate; the proportional coefficient and the derivative coefficient are both determined by looking up a table according to the current speed.

[0066] In some embodiments, before generating navigation control commands, the generation module 420 further includes: based on the current azimuth angle and the azimuth angle change rate, superimposing the product of the azimuth angle change rate and the total system delay time onto the current azimuth angle to obtain a predicted azimuth angle, which is used to determine the thruster differential speed command.

[0067] In some embodiments, the generation module 420, while generating the navigation control command, also includes: sending the expected vehicle body turning angular velocity to the searchlight subsystem, so that the searchlight subsystem can superimpose a compensation amount opposite to the vehicle body turning direction on the gimbal azimuth angle command. The compensation amount is determined by the product of the expected vehicle body turning angular velocity and the control period, and the direction is opposite to the vehicle body turning direction.

[0068] In some embodiments, after the navigation control command is generated, the generation module 420 further includes: limiting the navigation control command, including at least one of thruster differential speed limiting and command rate of change limiting.

[0069] In some embodiments, during the process of the control module 430 controlling the searchlight to continuously track the target, the method further includes: monitoring the validity of the target vector information; when no valid target vector information is received for several consecutive control cycles, or when the target azimuth angle exceeds the physical rotation range of the searchlight, the target is determined to be lost and a degradation strategy is initiated.

[0070] This invention also provides an amphibious vehicle, which includes a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the amphibious vehicle performs the amphibious vehicle searchlight-guided navigation control method described in any of the above embodiments.

[0071] This invention also provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program implements the amphibious vehicle searchlight-guided navigation control method described in any of the above embodiments. The storage medium can be a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), or the like.

[0072] This invention also provides a computer program product, which is tangibly stored on a computer-readable medium and includes computer-executable instructions. When executed, these computer-executable instructions implement the amphibious vehicle searchlight-guided navigation control method described in any of the above embodiments. The computer program product can be a software installation package and can be deployed in the amphibious vehicle via network download or local installation.

[0073] One or more embodiments of the present invention also provide an electronic device that can be used to implement the amphibious vehicle searchlight-guided navigation control method described in the above embodiments. The electronic device includes one or more processors, one or more memories coupled to the processors, and a communication module coupled to the processors.

[0074] The memory may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, at least one of the following: read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, hard disk, optical disc (CD), digital video disc (DVD), or other magnetic and / or optical storage. Examples of volatile memories include, but are not limited to, at least one of the following: random access memory (RAM), or other volatile memories that do not persist during the duration of a power outage. A computer program may be stored in the ROM, and when the processor executes the computer program, it implements the above-described amphibious vehicle searchlight-guided navigation control method.

[0075] In some embodiments, the program may be tangibly contained in a computer-readable medium, which may include a device (such as a memory) or other storage device accessible by the device. The program may be loaded from the computer-readable medium into RAM for execution. The computer-readable medium may include any type of tangible non-volatile memory, such as ROM, EPROM, flash memory, or hard disk, storing a computer program that, when executed by a processor, implements the aforementioned amphibious vehicle searchlight-guided navigation control method.

[0076] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When these computer program instructions are loaded and executed on a server or terminal, they generate all or part of the processes or functions described in the embodiments of this application. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic cable, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to the server or terminal, or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, and magnetic tape), an optical medium (e.g., digital video disc (DVD), etc.), or a semiconductor medium (e.g., solid-state drive).

[0077] Furthermore, although the operations are described in a specific order, this should be understood as requiring that such operations be performed in the specific order shown or in sequential order, or requiring that all illustrated operations be performed to achieve the desired result. In certain environments, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of this application. Certain features described in the context of individual embodiments may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented individually or in any suitable sub-combination in multiple implementations.

[0078] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

[0079] The above description is merely an exemplary embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for controlling the navigation of an amphibious vehicle guided by a searchlight, characterized in that, include: The target vector information output after the searchlight locks onto the target is acquired, and the target vector information includes at least the azimuth angle of the target relative to the vehicle body; Based on the target vector information and the current vehicle status information, a navigation control command is generated; The navigation control commands are sent to the corresponding actuators, and the searchlights are controlled to continuously track the target, forming a closed-loop cooperative control.

2. The method according to claim 1, characterized in that, Before acquiring the target vector information output after the searchlight locks onto the target, the procedure further includes: receiving a target lock command input by the driver, or receiving a target selection command on the touchscreen, and controlling the searchlight to align with and lock onto the target.

3. The method according to claim 1, characterized in that, The current vehicle status information includes at least one of the following: current speed, vehicle roll angle, driving mode, and vehicle attitude angle.

4. The method according to claim 1, characterized in that, The generation of the thruster differential command adopts a proportional-derivative control law, wherein the control command is composed of the superposition of the proportional term of the azimuth deviation and the derivative term of the azimuth rate of change; the proportional coefficient and the derivative coefficient are both determined by looking up a table according to the current speed.

5. The method according to claim 4, characterized in that, The target vector information also includes an estimated distance; the estimated distance is calculated based on the installation height and pitch angle of the searchlight, the vehicle pitch angle, and the vehicle's draft, using trigonometric relationships.

6. The method according to claim 1, characterized in that, The process of generating navigation control commands also includes sending the expected vehicle body turning angular velocity to the searchlight subsystem, so that the searchlight subsystem can superimpose a compensation amount opposite to the vehicle body turning direction on the gimbal azimuth angle command. The compensation amount is determined by the product of the expected vehicle body turning angular velocity and the control period, and the direction is opposite to the vehicle body turning direction.

7. The method according to claim 1, characterized in that, After the navigation control command is generated, the method further includes: limiting the navigation control command, including at least one of thruster differential speed limiting and command rate of change limiting.

8. The method according to claim 1, characterized in that, The process of controlling the searchlight to continuously track the target also includes: monitoring the validity of the target vector information; when no valid target vector information is received for several consecutive control cycles, or when the target azimuth angle exceeds the physical rotation range of the searchlight, the target is determined to be lost and a degradation strategy is initiated.

9. The method according to claim 1, characterized in that, In response to the demand for amphibious vehicles to land, the orientation of the dock is determined; based on the slope of the dock, the slope is extended underwater to delineate a strip-shaped navigation area; a series of virtual target points are selected along the slope normal. The system selects virtual targets from the sequence of virtual targets, from near to far, as the current tracking target, and performs navigation control for the current tracking target. When the horizontal distance between the vehicle and the current virtual target is less than a set threshold, the system switches to the next, more distant virtual target as the new current tracking target.

10. A navigation control device for an amphibious vehicle guided by a searchlight, characterized in that, include: The acquisition module is configured to acquire target vector information output after the searchlight locks onto a target, the target vector information including at least the azimuth angle of the target relative to the vehicle body; The generation module is configured to generate navigation control commands based on the target vector information and the current vehicle status information; The control module is configured to send the navigation control commands to the corresponding actuators and control the searchlight to continuously track the target, forming a closed-loop cooperative control.

11. An amphibious vehicle, characterized in that, Also includes: Memory, used to store computer programs; A processor for executing the computer program to implement the method according to any one of claims 1 to 9.

Images