A method for assisting the propulsion and stabilizing the posture of a seabed mining vehicle under the condition of local subsidence

Abstract

The application discloses a kind of seabed mining car local subsidence working condition under the propulsion auxiliary stable posture and escapes from predicament control method, comprising: obtaining seabed mining car running state information in the process of bottom walking;Based on the deviation of at least two state parameters and preset threshold value, it is judged whether to enter abnormal blocked state, and the abnormal working condition categories such as local subsidence, one-side blocked, track idling, steering limited or attitude over-limit are identified;According to the identified category, match target mode from multiple escape control modes;Based on target mode, determine the auxiliary thrust distribution scheme of vector propeller in multidimension, and control track walking mechanism to execute the driving action adjustment strategy coordinated with propeller thrust;After meeting preset escape condition, determine that escape is completed, gradually remove propeller auxiliary thrust at set slow change rate and synchronously restore track normal drive.The application improves the escape ability and vehicle body posture stability under abnormal working condition.

Description

Technical Field

[0001] This invention relates to the field of deep-sea resource development and seabed mining equipment control technology, and in particular to a propulsion-assisted attitude stabilization and escape control method for seabed mining vehicles in the case of partial subsidence. Background Technology

[0002] Deep-sea polymetallic nodules, cobalt-rich crusts, and phosphorite mineral resources are mostly distributed on the surface of seabed sediments or in areas with complex micro-topography. Seabed sediments are typically characterized by low bearing capacity, uneven distribution of soft and hard materials, and decreased strength after disturbance. During seabed mining operations, seabed mining vehicles are prone to problems such as localized subsidence, unilateral obstruction, track spinning, restricted steering, and abnormal vehicle posture due to excessive local ground pressure, uneven distribution of track traction, or sudden changes in terrain.

[0003] Existing seabed mining vehicles typically use tracked locomotives for seabed movement. While tracked locomotives offer a large ground contact area and traction capacity, when sinking or becoming obstructed on soft seabeds, simply increasing the track drive torque or widening the speed difference between the left and right tracks can easily lead to continuous digging of the seabed sediment by the tracks, increasing the slip ratio, further increasing the amount of subsidence, and even causing the vehicle to sink further. Especially when one track is obstructed or partially subsides, the vehicle may also exhibit abnormal roll, pitch, or yaw, affecting the attitude stability of the sampling equipment and the overall safety of the vehicle's movement.

[0004] Some seabed mining equipment is equipped with thruster auxiliary devices to provide auxiliary thrust or perform attitude correction during movement. However, existing control methods typically only compensate for thrust based on vehicle motion or attitude deviations, lacking the ability to classify and identify abnormal conditions such as local subsidence, unilateral obstruction, track idling, restricted steering, and attitude exceeding limits. They also lack strategies for coordinating thruster force distribution with track movement for different abnormal conditions. If auxiliary thrust is output directly without distinguishing the type of abnormality, problems such as unreasonable thrust direction, mismatch between track and thruster movements, and increased attitude fluctuations during extrication from difficult situations may occur.

[0005] Therefore, it is necessary to propose a propulsion-assisted attitude stabilization and escape control method for seabed mining vehicles under local subsidence conditions. After the seabed mining vehicle is abnormally obstructed, the abnormal obstruction state can be judged based on state parameters such as subsidence amount, track slip ratio, track drive load, vehicle speed, roll angle, pitch angle and yaw angular velocity. The abnormal condition type can be further identified, and the corresponding escape control mode can be selected according to the abnormal condition type. The vector thruster and track walking mechanism can be controlled in a coordinated manner to enable the vehicle to escape and resume stable walking under attitude control conditions. Summary of the Invention

[0006] To address the problem that existing subsea mining vehicles encountering localized subsidence, unilateral obstruction, track spinning, restricted steering, or excessive posture during travel on soft seabeds, simply relying on increasing traction through the tracks can easily lead to track digging, increased slippage, and secondary subsidence. Furthermore, conventional thruster-assisted control is insufficient for targeted extrication based on the specific type of abnormal working condition. Therefore, this invention provides a propulsion-assisted posture stabilization and extrication control method for subsea mining vehicles in the event of localized subsidence.

[0007] On the one hand, to achieve the above objectives, the present invention provides a propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle, comprising: The system acquires the operating status information of the seabed mining vehicle during its landing and travel process, and determines whether the seabed mining vehicle has entered an abnormal obstructed working state based on the deviation relationship between at least two parameters in the operating status information and the corresponding preset threshold. After determining that an abnormal obstructed working state has been entered, the category of the current abnormal working condition is identified based on one or more of the following factors: spatial distribution characteristics of the subsidence amount, difference in slip rate of left and right tracks, difference in drive load of left and right tracks, vehicle attitude angle offset, and heading angular velocity tracking deviation. The category includes one or more of the following: local subsidence, unilateral obstruction, track idling, steering restriction, and attitude over-limit. Based on the identified abnormal working condition category, the corresponding target escape control mode is matched from the preset escape control modes. Based on the target escape control mode, the auxiliary thrust distribution scheme of the vector thruster in multiple dimensions is determined, and the track walking mechanism is controlled to execute a drive action adjustment strategy that coordinates with the thruster thrust. During the escape control process, the vehicle's motion state and grounding state are monitored. When the preset escape success conditions are met, the escape is determined to be complete. The auxiliary thrust of the vector thruster is gradually removed according to the set gradual change rate, and the normal drive output of the track walking mechanism is restored simultaneously.

[0008] Preferably, the conditions for determining the abnormal obstructed working state include: grounding subsidence greater than a first subsidence threshold, track slip rate greater than a first slip threshold, track drive load greater than a first load threshold, vehicle real-time speed less than a first speed threshold, and vehicle roll angle or vehicle pitch angle greater than a first attitude threshold. When any two or more of the above conditions are met simultaneously, it is determined that the system is in the abnormally obstructed working state.

[0009] Preferably, the abnormal working condition category includes one or more of the following: local subsidence, unilateral obstruction, track spinning, steering limitation, and attitude exceeding limits; The identification methods for different working condition categories include: When the local anomaly in the subsidence distribution occurs and the corresponding attitude angle shifts positively, it is identified as a local subsidence condition. When the difference in slip ratio or drive load between the left and right tracks exceeds a preset difference threshold, it is identified as a unilateral obstruction condition. When the difference between the theoretical driving speed of the track and the real-time speed of the vehicle exceeds the preset idling threshold, it is identified as a track idling condition. When there is an active steering command and the deviation between the actual heading angular velocity and the target heading angular velocity exceeds the preset steering deviation threshold, it is identified as a steering-restricted condition. When the roll angle or pitch angle of the vehicle exceeds the second attitude threshold, it is identified as an attitude over-limit condition.

[0010] Preferably, the preset escape control modes include a local sinking and load reduction mode, a unilateral obstruction escape mode, a track idling suppression mode, a steering restriction assistance mode, and an attitude over-limit stabilization mode. In the local subsidence load reduction mode, the vertical load reduction thrust component of the vector thruster in the corresponding area is increased according to the location of the subsidence distribution, and the drive output of the corresponding side track is limited. In the single-sided obstruction escape mode, the obstructed track is controlled to perform torque limiting, short-term reverse or swinging actions, and the vector thruster is controlled to output lateral or oblique horizontal escape thrust.

[0011] Preferably, in the track idling suppression mode, the target track speed is reduced and the rate of increase of the drive torque is limited, while the vector thruster is controlled to output horizontal auxiliary thrust and vertical load reduction thrust. In the steering-limited auxiliary mode, the left and right vector thrusters are controlled to output differentiated horizontal thrust according to the deviation of the heading angular velocity, forming an auxiliary yaw torque and limiting the differential amplitude of the left and right tracks.

[0012] Preferably, in the attitude over-limit stabilization mode, the vector thruster outputs differentiated vertical thrust according to the offset of the roll angle or pitch angle, generates attitude correction torque, and reduces the track drive output until the vehicle attitude angle returns to the preset safe range.

[0013] Preferably, the preset conditions for successful escape include: The vehicle's real-time speed returns to the preset speed range, the track slip rate decreases to the preset slip range, the ground subsidence stops increasing, and the vehicle's attitude angle returns to the preset safe range. When at least one of the above conditions is met and the preset time is reached continuously and stably, the escape is deemed successful.

[0014] Preferably, if the preset escape success condition is not met within the preset escape time limit, an escape failure protection operation is executed; The escape failure protection operations include: reducing track drive output, maintaining or adjusting the attitude correction thrust of the vector thruster, suspending data acquisition operations, or issuing a manual intervention prompt.

[0015] On the other hand, to achieve the above objectives, the present invention also provides a propulsion-assisted attitude stabilization and escape control system for a submerged underwater mining vehicle, comprising: The status information acquisition module is used to acquire the operating status information of the seabed mining vehicle during its landing and movement. An abnormal state determination module is used to determine whether the seabed mining vehicle has entered an abnormal obstructed working state based on the deviation relationship between at least two parameters in the operating status information and the corresponding preset threshold. The operating condition type identification module is used to identify the category to which the current abnormal operating condition belongs based on the comparison information in the operating status information; The control mode matching module is used to match the corresponding target escape control mode according to the abnormal working condition category. The thruster thrust distribution module is used to determine a multi-dimensional auxiliary thrust distribution scheme for the vector thruster based on the target escape control mode. The track cooperative control module is used to control the track walking mechanism to perform cooperative drive adjustments according to the target escape control mode. The vehicle traction status monitoring module is used to determine whether the conditions for successful traction are met based on the vehicle's movement status and grounding status. The recovery control module is used to gradually remove the auxiliary thrust of the vector thruster according to the set gradual change rate and simultaneously restore the normal drive output of the tracks after successful escape from trouble.

[0016] Compared with the prior art, the present invention has the following advantages and technical effects: (1) The present invention provides a propulsion-assisted attitude stabilization and escape control method for a seabed mining vehicle under local subsidence conditions. After the seabed mining vehicle experiences abnormal conditions such as local subsidence, unilateral obstruction, track idling, steering restriction or attitude over-limit, it can judge the abnormal obstruction and classify the abnormal conditions according to the vehicle status parameters, avoid using the same escape action under different abnormal conditions, and improve the pertinence of escape control.

[0017] (2) By decomposing the auxiliary thrust of the vector thruster into vertical load reduction component, horizontal escape component and attitude recovery component, and coordinating it with track torque limiting, differential speed, short-term reverse or low-speed oscillation action, the present invention can reduce the seabed sediment excavation, track slippage aggravation and vehicle sinking caused by simply increasing track torque.

[0018] (3) When the attitude exceeds the limit or the local subsidence is uneven, the present invention can first achieve vehicle stability by limiting the vertical thrust and track traction, and then perform the corresponding escape action, thereby improving the attitude stability and walking recovery ability of the seabed mining vehicle under the abnormal obstruction of soft bottom.

[0019] (4) After the extrication is completed, the present invention gradually reduces the auxiliary thrust of the vector thruster by a preset change rate and gradually restores the track traction output, which can reduce the secondary sinking or attitude fluctuation caused by thrust change and traction change, and improve the continuous operation capability of the seabed mining vehicle after abnormal working conditions. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flowchart of a propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions, according to an embodiment of the present invention. Figure 2 This is a block diagram illustrating the identification of abnormal obstruction status under the local subsidence condition of an underwater mining vehicle according to an embodiment of the present invention. Figure 3 This is a schematic diagram illustrating the correspondence between abnormal working conditions and escape control modes of an underwater mining vehicle according to an embodiment of the present invention. Figure 4 This is a schematic diagram illustrating the coordinated control of the propulsion force and track movement of a seabed mining vehicle according to an embodiment of the present invention. Figure 5 This is a flowchart illustrating the successful escape judgment, escape failure protection, and recovery control of an underwater mining vehicle according to an embodiment of the present invention. Detailed Implementation

[0021] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0023] This embodiment proposes a propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle, including: The system acquires the operating status information of the seabed mining vehicle during its landing and travel process, and determines whether the seabed mining vehicle has entered an abnormal obstructed working state based on the deviation relationship between at least two parameters in the operating status information and the corresponding preset threshold. After determining that an abnormal obstructed working state has been entered, the category of the current abnormal working condition is identified based on one or more of the following factors: spatial distribution characteristics of the subsidence amount, difference in slip rate of the left and right tracks, difference in drive load of the left and right tracks, vehicle attitude angle offset, and heading angular velocity tracking deviation. The category includes one or more of the following: local subsidence, unilateral obstruction, track idling, steering restriction, and attitude over-limit. Based on the identified abnormal working condition category, the corresponding target escape control mode is matched from the preset escape control modes. Based on the target escape control mode, the auxiliary thrust distribution scheme of the vector thruster in multiple dimensions is determined, and the track walking mechanism is controlled to execute a drive action adjustment strategy that coordinates with the thruster thrust. During the escape control process, the vehicle's motion state and grounding state are monitored. When the preset escape success conditions are met, the escape is determined to be complete. The auxiliary thrust of the vector thruster is gradually removed according to the set gradual change rate, and the normal drive output of the track walking mechanism is restored simultaneously.

[0024] Specifically, this embodiment mainly determines whether the seabed mining vehicle is in an abnormal obstruction state by acquiring state parameters such as the subsidence amount, track slip ratio, track drive load, actual vehicle speed, roll angle, pitch angle, and yaw angular velocity. After determining that the vehicle is in an abnormal obstruction state, it further identifies abnormal working condition types such as local subsidence, unilateral obstruction, track idling, steering restriction, or attitude over-limit. According to the abnormal working condition type, the corresponding escape control mode is selected, and the vertical load reduction component, horizontal escape component, and attitude recovery component of the vector thruster are coordinated and allocated. At the same time, the track is controlled to perform torque limiting, differential, short-term reverse, or low-speed oscillation actions. Finally, the success of escape is determined based on the actual vehicle speed, track slip ratio, subsidence amount, and vehicle attitude angle. After successful escape, the auxiliary thrust of the thruster is gradually reduced to restore the normal walking control of the seabed mining vehicle.

[0025] The operational status information includes subsidence amount, track slip ratio, track drive load, actual vehicle speed, roll angle, pitch angle, and yaw rate.

[0026] Furthermore, the conditions for determining the abnormal obstructed working state include: grounding subsidence greater than the first subsidence threshold, track slip rate greater than the first slip threshold, track drive load greater than the first load threshold, vehicle real-time speed less than the first speed threshold, and vehicle roll angle or vehicle pitch angle greater than the first attitude threshold. When any two or more of the above conditions are met simultaneously, it is determined that the system is in the abnormally obstructed working state.

[0027] Furthermore, the abnormal operating condition categories include one or more of the following: local subsidence, unilateral obstruction, track spinning, restricted steering, and attitude exceeding limits; The identification methods for different working condition categories include: When the local anomaly in the subsidence distribution occurs and the corresponding attitude angle shifts positively, it is identified as a local subsidence condition. When the difference in slip ratio or drive load between the left and right tracks exceeds a preset difference threshold, it is identified as a unilateral obstruction condition. When the difference between the theoretical driving speed of the track and the real-time speed of the vehicle exceeds the preset idling threshold, it is identified as a track idling condition. When there is an active steering command and the deviation between the actual heading angular velocity and the target heading angular velocity exceeds the preset steering deviation threshold, it is identified as a steering-restricted condition. When the roll angle or pitch angle of the vehicle exceeds the second attitude threshold, it is identified as an attitude over-limit condition.

[0028] Furthermore, the preset escape control modes include a local sinking and load reduction mode, a unilateral obstruction escape mode, a track idling suppression mode, a steering restriction assistance mode, and an attitude over-limit stabilization mode. Specifically, in the local subsidence load reduction mode, the subsidence side or subsidence area is determined according to the subsidence amount distribution, the vertical load reduction component of the vector thruster corresponding to the subsidence side or subsidence area is increased, and the traction output of the corresponding track is reduced or the torque growth rate of the corresponding track is limited.

[0029] In the single-sided obstruction escape mode, the obstructed track is controlled to perform torque limiting, short-term reverse or low-speed oscillation actions, the unobstructed track is controlled to maintain low-speed traction, and the vector thruster is controlled to output lateral or oblique horizontal escape force.

[0030] In the track slip suppression mode, the target track speed is reduced, the track torque growth rate is limited, and the vector thruster is controlled to provide horizontal auxiliary force and vertical load reduction force to reduce the track slip rate.

[0031] In the steering-limited assist mode, based on the deviation between the target heading angular velocity and the actual heading angular velocity, the left and right vector thrusters are controlled to output differential horizontal thrust to form an auxiliary yaw moment and limit the differential speed amplitude of the left and right tracks.

[0032] In the attitude over-limit stabilization mode, the left and right or front and rear vector thrusters are controlled to output different vertical thrust according to the roll angle or pitch angle, and the track traction output is reduced so that the vehicle attitude angle is restored to the preset safe range.

[0033] Furthermore, the preset conditions for successful escape include: The vehicle's real-time speed returns to the preset speed range, the track slip rate decreases to the preset slip range, the ground subsidence stops increasing, and the vehicle's attitude angle returns to the preset safe range. When at least one of the above conditions is met and the preset time is reached continuously and stably, the escape is deemed successful.

[0034] Furthermore, if the preset escape success condition is not met within the preset escape time limit, an escape failure protection operation is executed; The escape failure protection operations include: reducing track drive output, maintaining or adjusting the attitude correction thrust of the vector thruster, suspending data acquisition operations, or issuing a manual intervention prompt.

[0035] Once the vehicle is successfully freed, the vertical load reduction component, horizontal escape component, and attitude recovery component of the vector thruster are gradually reduced according to the preset rate of change, and the track traction output is gradually restored to avoid secondary sinking of the vehicle body or sudden attitude changes.

[0036] This embodiment also provides a propulsion-assisted attitude stabilization and escape control system for a submerged underwater mining vehicle, including: The status information acquisition module is used to acquire the operating status information of the seabed mining vehicle during its landing and movement. An abnormal state determination module is used to determine whether the seabed mining vehicle has entered an abnormal obstructed working state based on the deviation relationship between at least two parameters in the operating status information and the corresponding preset threshold. The operating condition type identification module is used to identify the category to which the current abnormal operating condition belongs based on the comparison information in the operating status information; The control mode matching module is used to match the corresponding target escape control mode according to the abnormal working condition category. The thruster thrust distribution module is used to determine a multi-dimensional auxiliary thrust distribution scheme for the vector thruster based on the target escape control mode. The track cooperative control module is used to control the track walking mechanism to perform cooperative drive adjustments according to the target escape control mode. The vehicle traction status monitoring module is used to determine whether the conditions for successful traction are met based on the vehicle's movement status and grounding status. The recovery control module is used to gradually remove the auxiliary thrust of the vector thruster according to the set gradual change rate and simultaneously restore the normal drive output of the tracks after successful escape from trouble.

[0037] To more clearly illustrate the technical solution of the present invention, specific embodiments are provided below for description: like Figure 1As shown, this embodiment provides a propulsion-assisted attitude stabilization and escape control method for seabed mining vehicles under partial subsidence conditions, applicable to seabed mining vehicles with tracked walking mechanisms and vector thrusters. This method does not limit the specific vehicle structure, number of tracks, thruster installation position, or data acquisition device form of the seabed mining vehicle; as long as it can acquire vehicle status parameters during seabed landing and can perform joint control through the tracked walking mechanism and vector thrusters, the method described in this embodiment is applicable.

[0038] S1. Obtain the state parameters of the seabed mining vehicle during its landing and walking process.

[0039] Specifically, the state parameters include sinking amount, track slip ratio, track drive load, actual vehicle speed, roll angle, pitch angle, and yaw rate.

[0040] The amount of subsidence can be obtained by distance sensors, pressure sensors, grounding status detection devices, or visual perception devices installed on the bottom of the vehicle body, the track support area, or around the vehicle body; the track slip ratio can be calculated based on the difference between the theoretical track speed and the actual vehicle speed; the track drive load can be estimated by the track drive motor current, hydraulic motor pressure, or drive torque; the actual vehicle speed, roll angle, pitch angle, and yaw rate can be obtained by inertial measurement units, deep-sea navigation and positioning devices, or integrated navigation systems.

[0041] S2, determine whether the seabed mining vehicle is in an abnormal obstruction state.

[0042] Specifically, the control system determines whether the vehicle is in an abnormal obstruction state based on the subsidence amount, track slip ratio, track drive load, actual vehicle speed, and vehicle attitude angle. When at least two of the following conditions are met simultaneously: the subsidence amount exceeds a preset subsidence threshold (first subsidence threshold), the track slip ratio exceeds a preset slip threshold (first slip threshold), the track drive load exceeds a preset load threshold (first load threshold), the actual vehicle speed is lower than a preset speed threshold (first speed threshold), or the roll angle or pitch angle exceeds a preset attitude threshold (first attitude threshold), the seabed mining vehicle is determined to be in an abnormal obstruction state.

[0043] By using at least two state conditions for joint judgment, misjudgments caused by single sensor errors or short-term disturbances can be reduced.

[0044] S3, Abnormal operating condition type identification steps, including: like Figure 2 As shown, when the seabed mining vehicle is determined to be in an abnormal obstruction state, the control system further identifies the type of abnormal working condition based on the subsidence distribution, the difference in slip ratio between the left and right tracks, the difference in drive load between the left and right tracks, the vehicle attitude angle, and the heading angular velocity.

[0045] Abnormal operating conditions include one or more of the following: local subsidence, unilateral obstruction, track spinning, restricted steering, and attitude exceeding limits.

[0046] When the amount of subsidence on a certain side, a certain corner, or a local area in front or behind exceeds the preset subsidence threshold, and the actual speed of the vehicle decreases or the roll angle or pitch angle shifts, it is identified as local subsidence.

[0047] When the difference between the slip ratios of the left and right tracks or the difference between the drive loads of the left and right tracks exceeds the preset difference threshold, and the vehicle body exhibits abnormal yaw or roll changes, it is identified as a single-sided obstruction.

[0048] When the theoretical speed of the track is high while the actual speed of the vehicle body is low, and the track slip rate continuously exceeds the preset slip threshold, it is identified as track idling.

[0049] When a steering control command is present and the left and right tracks have performed differential action, but the actual heading angular velocity is lower than the target heading angular velocity, it is identified as a steering limitation.

[0050] When the roll angle or pitch angle exceeds the preset attitude threshold, it is identified as an attitude over-limit.

[0051] S4. Steps for selecting the escape control mode include: like Figure 3 As shown, the control system selects the corresponding escape control mode according to the type of abnormal operating condition.

[0052] The escape control modes include one or more of the following: local sinking and load reduction mode, unilateral obstruction escape mode, track idling suppression mode, steering restriction assistance mode, and attitude over-limit stabilization mode.

[0053] In actual control, if multiple abnormal operating conditions occur simultaneously, the control mode can be selected according to the preset priority.

[0054] Specifically, when attitude over-limit occurs simultaneously with other abnormal working conditions, the attitude over-limit stabilization mode is entered first; when local sinking and track idling occur simultaneously, the local sinking load reduction mode is entered first; when unilateral obstruction and steering restriction occur simultaneously, the unilateral obstruction relief mode is executed first, followed by the steering restriction assistance mode.

[0055] S5, the thrust distribution steps of the vectoring thruster, include: like Figure 4 As shown, the control system determines the thrust direction and magnitude of the vector thruster according to the escape control mode.

[0056] The auxiliary thrust of a vector thruster includes vertical load reduction component, horizontal escape component, and attitude recovery component.

[0057] The vertical load reduction component is used to reduce the ground load on the tracks or in the sunken area; the horizontal get-out component is used to provide auxiliary force to get out of the obstructed area forward, laterally, or obliquely; and the attitude recovery component is used to correct the roll angle, pitch angle, or yaw attitude.

[0058] In the localized subsidence and load reduction mode, the control system determines the subsidence side or area based on the subsidence distribution and increases the vertical load reduction component of the vector thruster corresponding to that subsidence side or area to reduce the local grounding load and prevent the vehicle from sinking further. If necessary, the control system can superimpose a small horizontal forward auxiliary force to allow the vehicle to slowly leave the subsidence area.

[0059] In the unilateral obstruction escape mode, the control system controls the vector thrusters to output lateral or oblique horizontal escape force based on the position of the obstructed side, enabling the vehicle to escape horizontally away from the obstructed side or out of the obstruction area. At the same time, the control system can suppress the roll attitude change caused by unilateral escape by outputting different vertical thrusts from the left and right thrusters.

[0060] In track slip suppression mode, the control system controls the vector thruster to provide a portion of the horizontal auxiliary force to compensate for insufficient track traction, and appropriately increases the vertical load reduction force according to the amount of sinking and slip ratio, so that the track slip ratio gradually decreases.

[0061] In the steering-limited assist mode, the control system controls the left and right vector thrusters to output differential horizontal thrust based on the deviation between the target heading angular velocity and the actual heading angular velocity, so that the vehicle body generates an auxiliary yaw torque, thereby assisting the seabed mining vehicle to complete the steering action.

[0062] In attitude over-limit stabilization mode, the control system controls the left and right or front and rear vector thrusters to output differential vertical thrust based on the roll or pitch angle, so that the vehicle's attitude angle returns to the preset safe range. If the attitude over-limit is high, the control system can temporarily suspend the horizontal escape force output and prioritize attitude recovery.

[0063] S6, Track Motion Control Steps, including: While distributing auxiliary thrust to the vector thrusters, the control system controls the tracks to perform torque limiting, differential, short-term reverse, or low-speed oscillation actions according to the traction control mode.

[0064] In the local subsidence and load reduction mode, the control system reduces the traction output of the track corresponding to the subsided side or subsided area, or limits its torque growth rate, and controls the track on the non-subsided side to maintain low-speed traction.

[0065] In the single-sided obstruction escape mode, the control system controls the obstructed track to perform torque limiting, short-term reverse or low-speed oscillation actions, controls the unobstructed track to maintain low-speed positive traction, and cooperates with the lateral or oblique horizontal escape component force of the vector thruster to enable the vehicle to escape from the single-sided obstruction state.

[0066] In track slip suppression mode, the control system reduces the target track speed, limits the track torque growth rate, and prevents the track from continuously digging through seabed sediments; at the same time, it uses vector thrusters to provide horizontal auxiliary force and vertical load reduction force, reducing slip ratio and restoring effective traction.

[0067] In the steering-limited assist mode, the control system maintains a small differential speed between the left and right tracks and limits the differential speed amplitude between the left and right tracks to avoid slipping on the spot or excessive disturbance of sediment due to excessive differential speed; at the same time, it works with the differential horizontal thrust of the left and right vector thrusters to form an auxiliary yaw torque.

[0068] In the attitude over-limit stabilization mode, the control system reduces the track traction output, and if necessary, suspends the data acquisition operation or reduces the data acquisition load. After the vehicle attitude angle returns to the preset safe range, it will enter other escape control modes.

[0069] S7, the steps for determining successful escape include: like Figure 5 As shown, after executing the thruster distribution and track movement control, the control system continuously monitors the vehicle's actual speed, track slip ratio, sinking amount, roll angle, and pitch angle. When one or more of the following conditions are met: the vehicle's actual speed returns to the preset speed range, the track slip ratio decreases to the preset slip range, the sinking amount no longer increases, and the roll angle and pitch angle return to the preset attitude range, the vehicle is considered successfully freed from its predicament.

[0070] In a preferred embodiment, the control system may require the above conditions to remain stable for multiple consecutive control cycles before determining that the escape from the obstacle has been successful, so as to avoid misjudgment caused by short-term speed fluctuations or attitude fluctuations.

[0071] If the vehicle fails to escape from the obstacle within a preset control cycle, the control system executes an escape failure protection mechanism. This protection includes one or more of the following: reducing track traction output, maintaining or adjusting the attitude recovery component of the vector thrusters, suspending data acquisition, recording abnormal status information, or issuing a manual takeover prompt. By implementing this escape failure protection, the system can prevent the vehicle from further sinking if it continues to increase track output when unable to escape the obstacle.

[0072] S8, Post-Escape Control Recovery Procedures, including: Once the successful extrication is determined, the control system gradually reduces the vertical load-reducing component, horizontal escape component, and attitude recovery component of the vector thruster according to a preset rate of change, and gradually restores the track traction output, allowing the seabed mining vehicle to smoothly transition from the extrication control state to the normal walking control state. This gradual recovery method reduces secondary sinking and attitude fluctuations caused by sudden changes in thruster or track traction.

[0073] In a preferred embodiment of this application, during the soft-bottom mining operation, if the subsidence of the left front track area exceeds a preset subsidence threshold, the slippage rate of the left track increases, the driving load of the left track increases, the actual speed of the vehicle decreases, and the roll angle increases. Based on these parameters, the control system determines that the vehicle is in an abnormal obstruction state and identifies it as local subsidence accompanied by unilateral obstruction. The control system first enters an attitude over-limit stabilization mode, controlling the left and right vector thrusters to output differential vertical thrust, causing the roll angle to return to a safe range. Then, it enters a local subsidence load reduction mode, increasing the vertical load reduction component corresponding to the left front subsidence area and reducing the traction output of the left track. Finally, it enters a unilateral obstruction escape mode, controlling the left track to briefly reverse or swing at low speed, while the right track provides low-speed forward traction, and simultaneously controlling the vector thrusters to output a diagonal horizontal escape component. Once the vehicle's actual speed recovers, the track slip rate decreases, the amount of sinking stops increasing, and the roll angle returns to the preset range, the control system determines that the vehicle has successfully escaped the predicament and gradually reduces the thruster's auxiliary thrust according to the preset rate of change, restoring normal travel control.

[0074] In another preferred embodiment of this application, when the seabed mining vehicle executes a steering command, the left and right tracks are already under differential speed control, but the actual heading angular velocity remains lower than the target heading angular velocity, while the track slip ratio increases. The control system identifies this as restricted steering accompanied by track spinning. The control system reduces the differential speed amplitude of the left and right tracks, limits the track torque growth rate, and controls the left and right vector thrusters to output differential horizontal thrust to form an auxiliary yaw torque, enabling the vehicle to complete the steering while reducing seabed sediment disturbance. Once the actual heading angular velocity returns to the target range and the track slip ratio decreases, the control system gradually reduces the differential horizontal thrust of the thrusters, restoring normal travel control.

[0075] By applying the technical solution of this invention, after a seabed mining vehicle experiences abnormal working conditions such as partial subsidence, unilateral obstruction, track idling, steering limitation, or attitude over-limit, a corresponding escape control mode can be adopted according to different abnormality types. Through the coordinated control of the vertical load reduction component, horizontal escape component, and attitude recovery component of the vector thruster with track torque limiting, differential speed, short-term reverse or low-speed oscillation actions, the continuous digging of the track and the continued sinking of the vehicle are reduced, thereby improving the seabed mining vehicle's escape ability, attitude stability, and continuous operation capability under abnormal obstruction conditions.

[0076] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under localized subsidence conditions, characterized in that, include: The system acquires the operating status information of the seabed mining vehicle during its landing and travel process, and determines whether the seabed mining vehicle has entered an abnormal obstructed working state based on the deviation relationship between at least two parameters in the operating status information and the corresponding preset threshold. After determining that an abnormal obstructed working state has been entered, the category of the current abnormal working condition is identified based on one or more of the following factors: spatial distribution characteristics of the subsidence amount, difference in slip rate of left and right tracks, difference in drive load of left and right tracks, vehicle attitude angle offset, and heading angular velocity tracking deviation. The category includes one or more of the following: local subsidence, unilateral obstruction, track idling, steering restriction, and attitude over-limit. Based on the identified abnormal working condition category, the corresponding target escape control mode is matched from the preset escape control modes. Based on the target escape control mode, the auxiliary thrust distribution scheme of the vector thruster in multiple dimensions is determined, and the track walking mechanism is controlled to execute a drive action adjustment strategy that coordinates with the thruster thrust. During the escape control process, the vehicle's motion state and grounding state are monitored. When the preset escape success conditions are met, the escape is determined to be complete. The auxiliary thrust of the vector thruster is gradually removed according to the set gradual change rate, and the normal drive output of the track walking mechanism is restored simultaneously.

2. The propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions as described in claim 1, characterized in that, The conditions for determining the abnormal obstructed working state include: grounding subsidence greater than the first subsidence threshold, track slip rate greater than the first slip threshold, track drive load greater than the first load threshold, vehicle real-time speed less than the first speed threshold, and vehicle roll angle or vehicle pitch angle greater than the first attitude threshold. When any two or more of the above conditions are met simultaneously, it is determined that the system is in the abnormally obstructed working state.

3. The propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions as described in claim 1, characterized in that, The abnormal operating condition categories include one or more of the following: local subsidence, unilateral obstruction, track spinning, steering restriction, and attitude exceeding limits. The identification methods for different working condition categories include: When the local anomaly in the subsidence distribution occurs and the corresponding attitude angle shifts positively, it is identified as a local subsidence condition. When the difference in slip ratio or drive load between the left and right tracks exceeds a preset difference threshold, it is identified as a unilateral obstruction condition. When the difference between the theoretical driving speed of the track and the real-time speed of the vehicle exceeds the preset idling threshold, it is identified as a track idling condition. When there is an active steering command and the deviation between the actual heading angular velocity and the target heading angular velocity exceeds the preset steering deviation threshold, it is identified as a steering-restricted condition. When the roll angle or pitch angle of the vehicle exceeds the second attitude threshold, it is identified as an attitude over-limit condition.

4. The propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions as described in claim 1, characterized in that, The preset escape control modes include local sinking and load reduction mode, unilateral obstruction escape mode, track idling suppression mode, steering restriction assistance mode, and attitude over-limit stabilization mode. In the local subsidence load reduction mode, the vertical load reduction thrust component of the vector thruster in the corresponding area is increased according to the location of the subsidence distribution, and the drive output of the corresponding side track is limited. In the single-sided obstruction escape mode, the obstructed track is controlled to perform torque limiting, short-term reverse or swinging actions, and the vector thruster is controlled to output lateral or oblique horizontal escape thrust.

5. The propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions as described in claim 4, characterized in that, In the track idling suppression mode, the target track speed is reduced and the rate of increase of the drive torque is limited, while the vector thruster is controlled to output horizontal auxiliary thrust and vertical load reduction thrust. In the steering-limited auxiliary mode, the left and right vector thrusters are controlled to output differentiated horizontal thrust according to the deviation of the heading angular velocity, forming an auxiliary yaw torque and limiting the differential amplitude of the left and right tracks.

6. The propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions as described in claim 4, characterized in that, In the attitude over-limit stabilization mode, the vector thruster outputs differentiated vertical thrust according to the offset of the roll angle or pitch angle, generates attitude correction torque, and reduces the track drive output until the vehicle attitude angle returns to the preset safe range.

7. The propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions as described in claim 1, characterized in that, The preset conditions for successful escape include: The vehicle's real-time speed returns to the preset speed range, the track slip rate decreases to the preset slip range, the ground subsidence stops increasing, and the vehicle's attitude angle returns to the preset safe range. When at least one of the above conditions is met and the preset time is reached continuously and stably, the escape is deemed successful.

8. The propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under local subsidence conditions as described in claim 1, characterized in that, If the preset escape success conditions are not met within the preset escape time limit, an escape failure protection operation is executed; The escape failure protection operations include: reducing track drive output, maintaining or adjusting the attitude correction thrust of the vector thruster, suspending data acquisition operations, or issuing a manual intervention prompt.

9. A propulsion-assisted attitude stabilization and escape control system for a submerged underwater mining vehicle under partial subsidence conditions, used to implement the propulsion-assisted attitude stabilization and escape control method for a submerged underwater mining vehicle under partial subsidence conditions as described in any one of claims 1-8, characterized in that, include: The status information acquisition module is used to acquire the operating status information of the seabed mining vehicle during its landing and movement. An abnormal state determination module is used to determine whether the seabed mining vehicle has entered an abnormal obstructed working state based on the deviation relationship between at least two parameters in the operating status information and the corresponding preset threshold. The operating condition type identification module is used to identify the category to which the current abnormal operating condition belongs based on the comparison information in the operating status information; The control mode matching module is used to match the corresponding target escape control mode according to the abnormal working condition category. The thruster thrust distribution module is used to determine a multi-dimensional auxiliary thrust distribution scheme for the vector thruster based on the target escape control mode. The track cooperative control module is used to control the track walking mechanism to perform cooperative drive adjustments according to the target escape control mode. The vehicle traction status monitoring module is used to determine whether the conditions for successful traction are met based on the vehicle's movement status and grounding status. The recovery control module is used to gradually remove the auxiliary thrust of the vector thruster according to the set gradual change rate and simultaneously restore the normal drive output of the tracks after successful escape from trouble.

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