Cross-country stuck vehicle autonomous escape method and system

Abstract

The application discloses a kind of off-road stuck car autonomous escape method and system, including according to wheel speed difference positioning stuck wheel, determine sinking grade in combination with vehicle body pitch angle and roll angle, output stuck wheel position and vehicle body posture information;Generation torque oscillation distribution strategy, make vehicle body produce periodic pitch oscillation to change wheel and sand contact state, adjust each suspension height in combination with vehicle body roll angle;According to sinking grade, start stuck wheel side tire valve core heating, make tire gas temperature rise and pressure rise after pressure relief to target tire pressure through heat conduction by valve core;Continuously monitor wheel speed change rate and vehicle body posture angle, when stuck wheel speed recovers to average level of driving wheel and vehicle body pitch angle falls back to stable range, stop torque oscillation and latch current suspension height parameter.The application can improve the success rate, control coordination and intelligent level of off-road stuck car autonomous escape.

Description

Technical Field

[0001] This invention relates to the field of intelligent vehicle control technology, and in particular to a method and system for autonomous extrication of a vehicle stuck in an off-road obstacle. Background Technology

[0002] With the continuous development of intelligent off-road vehicles, all-terrain vehicles, and new energy off-road platforms, the autonomous traversal capability of vehicles in complex terrains with low adhesion, such as sand, mud, snow, and gravel, has gradually become an important research direction for intelligent chassis control. Existing off-road traction control technologies mainly revolve around electronic limited-slip differential control, traction control systems, air suspension height adjustment, central tire inflation / deflation systems, and vehicle attitude perception. These technologies improve vehicle adhesion conditions through drive force distribution, vehicle height adjustment, or tire pressure regulation. In recent years, multi-sensor fusion sensing technology has been gradually applied to the field of intelligent chassis control. Utilizing multi-source information such as wheel speed sensors, inertial measurement units, and suspension height sensors, it enables vehicle operating status identification, providing richer data support for vehicle attitude estimation, road surface adhesion analysis, and autonomous traction control under off-road conditions. This has also driven the development of off-road vehicle autonomous traction technology from single-actuator control to multi-actuator collaborative control.

[0003] However, existing off-road extrication technologies still have certain limitations. On the one hand, most solutions mainly rely on wheel speed slippage rate or single attitude parameters to determine the stuck state, lacking sufficient analysis of the correlation between wheel sinking position, sinking degree, and vehicle attitude changes. This makes them susceptible to the influence of complex terrain and vehicle attitude changes, resulting in limited accuracy in identifying stuck vehicles. On the other hand, existing extrication control typically employs a single control method from drive force adjustment, air suspension adjustment, or tire pressure adjustment. There is a lack of unified coordination mechanism between the various actuators, failing to fully utilize the coupling effect between vehicle attitude changes, center of gravity transfer, and tire contact with the ground, resulting in limited improvement in wheel-ground contact. Furthermore, existing tire pressure adjustment systems generally rely on independent inflation and deflation devices, resulting in complex system structures and long response chains. In off-road stuck scenarios, it is difficult to achieve real-time coordination with vehicle power control and suspension control, affecting autonomous extrication efficiency and control stability. Summary of the Invention

[0004] In view of the problems existing in current off-road vehicle autonomous extrication methods, this invention is proposed. Therefore, the problem to be solved by this invention is how to provide an off-road vehicle autonomous extrication method and system.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] In a first aspect, the present invention provides a method for autonomous extrication of an off-road vehicle from a slump, comprising: acquiring real-time data from wheel speed sensors, air suspension altimeters and inertial measurement units, locating the stuck wheel based on wheel speed differences, determining the level of slump by combining the vehicle's pitch angle and roll angle, and outputting the position of the stuck wheel and the vehicle's attitude information.

[0007] Based on the wheel position and sinking level, a torque oscillation distribution strategy is generated to make the vehicle body produce periodic pitch oscillations to change the contact state between the wheels and the sand, while adjusting the height of each suspension in combination with the vehicle body roll angle.

[0008] According to the level of sinking, the tire valve core heating on the side of the sinking wheel is activated. The gas inside the tire is heated and pressurized through heat conduction and then released through the valve core to the target tire pressure.

[0009] Continuously monitor the wheel speed change rate and vehicle attitude angle. When the stuck wheel speed returns to the average level of the drive wheels and the vehicle pitch angle returns to a stable range, stop the torque oscillation and lock the current suspension height parameters, completing the autonomous extrication of the off-road vehicle from the stuck situation.

[0010] As a preferred embodiment of the off-road vehicle autonomous extrication method described in this invention, the step of locating the stuck wheel based on wheel speed difference includes:

[0011] Compare the wheel speeds of each drive wheel, calculate the deviation of each drive wheel from the overall average wheel speed of the drive wheels, and mark a drive wheel as a suspected trap wheel when it continuously exhibits a wheel speed change pattern different from other drive wheels;

[0012] Read the data from the air suspension height gauge and analyze the height changes at the four suspension positions. If the suspension height at the suspected wheel sinking position continues to decrease, it indicates that the wheel is subjected to a continuous sinking effect.

[0013] Read the pitch and roll angle data output by the inertial measurement unit. If the front wheels get stuck, the pitch angle is shown as the front of the car tilting downwards. If the rear wheels get stuck, the pitch angle is shown as the rear of the car tilting downwards. If the left wheel gets stuck, the roll angle is shown as the car body tilting to the left. If the right wheel gets stuck, the roll angle is shown as the car body tilting to the right.

[0014] By analyzing the correspondence between the direction of suspension height change and the direction of vehicle attitude change, when the two are consistent, the suspected wheel trap is confirmed to be an actual wheel trap.

[0015] As a preferred embodiment of the off-road vehicle autonomous extrication method described in this invention, the determination of the subsidence level includes:

[0016] Calculate the degree of wheel speed deviation, suspension compression, and vehicle attitude deviation;

[0017] The wheel speed deviation is the ratio of the difference between the wheel speed of the trapped wheel and the average wheel speed of the drive wheel to the average wheel speed; the suspension compression is the difference between the real-time suspension height of the trapped wheel and the initial suspension height; the vehicle attitude deviation is the fusion value of the pitch angle change and the roll angle change between the current attitude angle and the initial attitude angle.

[0018] When all three indicators are within the first threshold, it is determined to be a level 1 subsidence; when any two of the three indicators reach the second threshold range and the remaining indicators do not exceed the second threshold, it is determined to be a level 2 subsidence; when all three indicators reach the corresponding range of the second threshold or when any one indicator exceeds the second threshold and the other two indicators reach the first threshold, it is determined to be a level 3 subsidence.

[0019] As a preferred embodiment of the off-road vehicle autonomous extrication method described in this invention, the torque oscillation distribution strategy includes:

[0020] Based on the vehicle's drive configuration, a torque distribution relationship between the drive wheels is established. A target torque sequence is generated by alternating outputs of the drive wheels according to the location of the stuck wheel. The alternating drive torque creates a periodic torque difference between the drive wheels, causing the vehicle body to oscillate back and forth around the pitch axis. This changes the contact pressure distribution and adhesion state between the stuck wheel and the sand, allowing the stuck wheel to gradually form the support point required for climbing during the oscillation process.

[0021] As a preferred embodiment of the off-road vehicle autonomous extrication method described in this invention, the adjustment of the suspension height includes:

[0022] The direction of suspension height adjustment is determined by the location of the stuck wheel. If the stuck wheel is on the left side of the vehicle, the right suspension is gradually raised while the left suspension is gradually lowered. If the stuck wheel is on the right side of the vehicle, the left suspension is gradually raised while the right suspension is gradually lowered. If the stuck wheel is at the front of the vehicle, the rear suspension provides more support. If the stuck wheel is at the rear of the vehicle, the front suspension provides more support.

[0023] The system continuously reads the feedback data from the air suspension height gauge, compares the feedback height with the target height, and maintains the current height without further adjustment once the actual height of each suspension reaches the target state. If the vehicle's attitude changes again, the system recalculates the new target suspension height and continues to adjust.

[0024] As a preferred embodiment of the off-road vehicle autonomous extrication method described in this invention, the step of activating the heating of the tire valve core on the side of the stuck wheel includes:

[0025] Based on the determined location of the stuck wheel, only the valve core heating device inside the tire corresponding to the stuck wheel is activated, while the other wheels remain in normal condition;

[0026] After the valve core heating device is activated, it continuously provides heat to the valve core metal structure, causing the temperature of the gas inside the tire to gradually increase.

[0027] When the tire pressure reaches the valve core release condition, the valve core automatically opens the exhaust channel, and the air inside the tire is slowly discharged through the valve core, causing the tire pressure to gradually decrease.

[0028] When the tire pressure drops to the target tire pressure, immediately stop heating the valve core to allow it to return to its normal sealing state.

[0029] As a preferred embodiment of the off-road vehicle autonomous extrication method described in this invention, the autonomous extrication of the off-road vehicle includes:

[0030] The system continuously collects data from wheel speed sensors, air suspension altitude gauges, and inertial measurement units to perform cyclical analysis of the vehicle's current operating status.

[0031] When the wheel speed of the stuck wheel no longer deviates continuously, the vehicle pitch and roll angles no longer change continuously in one direction, and the suspension height gradually remains constant, the vehicle is determined to have successfully escaped the predicament after multiple consecutive sampling cycles confirm that the speed remains consistent.

[0032] Stop the torque oscillation control of the drive system to restore the drive system to normal power output mode, stop the active height adjustment of the air suspension and save the current height of the four suspensions as the lock-in height after the traction is completed, turn off the valve core heating module and restore the tire pressure monitoring status to normal, and release the autonomous traction control mode to restore the normal driving control logic of the vehicle.

[0033] Secondly, the present invention provides an autonomous off-road vehicle extrication system based on multi-sensor fusion, which includes: a judgment module, used to acquire real-time data from wheel speed sensors, air suspension altimeters and inertial measurement units, locate the stuck wheel according to the wheel speed difference, determine the sinking level by combining the vehicle pitch angle and roll angle, and output the position of the stuck wheel and the vehicle attitude information.

[0034] The control module is used to generate a torque oscillation distribution strategy based on the wheel position and sinking level, so that the vehicle body produces periodic pitch oscillations to change the contact state between the wheels and the sand, and at the same time adjusts the height of each suspension in combination with the vehicle body roll angle.

[0035] The heating module is used to activate the tire valve core heating on the side of the wheel sinking according to the sinking level. The gas inside the tire is heated and pressurized through heat conduction and then released to the target tire pressure through the valve core.

[0036] The monitoring module continuously monitors the wheel speed change rate and vehicle attitude angle. When the wheel speed recovers to the average level of the drive wheels and the vehicle pitch angle returns to a stable range, the torque oscillation stops and the current suspension height parameters are locked, thus completing the autonomous extrication of the off-road vehicle from the stalemate.

[0037] Thirdly, the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of a method for autonomous vehicle extrication from off-road stagnation.

[0038] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, it implements the steps of a method for autonomous vehicle extrication from off-road stagnation.

[0039] The beneficial effects of this invention are as follows: By integrating multi-source sensing information such as wheel speed, air suspension height, and vehicle posture, this invention achieves accurate identification of the position and degree of sinking of the stuck wheels, providing a reliable basis for subsequent extrication control; by coordinating the control of torque oscillation, air suspension center of gravity adjustment, and dynamic tire pressure adjustment, the contact state between the wheels and the ground, the overall vehicle load distribution, and tire adhesion conditions are simultaneously optimized, effectively improving the ability of the stuck wheels to extricate themselves from the pit; at the same time, by combining the wheel speed change rate and vehicle posture to make real-time judgments on the extrication status, the invention can promptly end control and lock suspension parameters after the vehicle resumes stable driving, avoiding the impact of continuous intervention on vehicle driving stability, thereby improving the success rate, control coordination, and intelligence level of off-road vehicles autonomously extricating themselves from stuck situations. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a flowchart of a method for an off-road vehicle to autonomously extricate itself from a stuck situation. Detailed Implementation

[0042] To make the above-mentioned objects, features, and advantages of the present invention more readily understood, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0043] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0044] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0045] Reference Figure 1 This is the first embodiment of the present invention, which provides a method for autonomous vehicle extrication from off-road stagnation, comprising:

[0046] S1: Acquire real-time data from wheel speed sensors, air suspension altitude gauges, and inertial measurement units; locate the stuck wheel based on wheel speed differences; determine the sinking level by combining vehicle pitch and roll angles; and output the stuck wheel position and vehicle attitude information.

[0047] S2: Based on the position of the wheel stuck and the level of sinking, a torque oscillation distribution strategy is generated to make the vehicle body produce periodic pitch oscillations to change the contact state between the wheel and the sand, while adjusting the height of each suspension in combination with the body roll angle.

[0048] S3: Based on the sinking level, start heating the tire valve core on the side of the sinking wheel. Through heat conduction, the gas inside the tire is heated and pressurized, and then released through the valve core to the target tire pressure.

[0049] S4: Continuously monitors the wheel speed change rate and vehicle attitude angle. When the stuck wheel speed returns to the average level of the drive wheels and the vehicle pitch angle falls back to the stable range, the torque oscillation stops and the current suspension height parameters are locked to complete the extrication process.

[0050] Specifically, after the vehicle enters the driving state, the controller activates the autonomous traction monitoring function to synchronously collect data from the wheel speed sensors, air suspension altimeter, and inertial measurement unit.

[0051] Among them, the wheel speed sensor outputs the real-time rotational speed information of each wheel, the air suspension height gauge outputs the vehicle height information of the four suspension positions, and the inertial measurement unit outputs the vehicle pitch angle, roll angle and attitude change information. The controller performs time synchronization processing on various types of data according to a unified sampling time, so that the wheel speed information, suspension height information and vehicle attitude information acquired at the same time correspond to the same vehicle state.

[0052] The wheel speeds of each drive wheel are analyzed, the current wheel speeds of each drive wheel are compared, and the deviation of each drive wheel from the overall average wheel speed of the drive wheels is calculated.

[0053] When a certain drive wheel consistently exhibits a different wheel speed change pattern than the other drive wheels, the drive wheel is marked as a suspected stuck wheel, and further confirmation is made by combining the changes in vehicle attitude.

[0054] Read the data output from the air suspension height gauge and analyze the height changes at the four suspension positions. If the suspension height at the suspected wheel-trapping position continues to decrease, it indicates that the wheel is experiencing a continuous downward force.

[0055] The controller reads the pitch and roll angle data output by the inertial measurement unit and analyzes the overall attitude change direction of the vehicle body. If the front wheels get stuck, the pitch angle of the vehicle body is manifested as the front of the vehicle tilting downward; if the rear wheels get stuck, the pitch angle of the vehicle body is manifested as the rear of the vehicle tilting downward; if the left wheel gets stuck, the roll angle of the vehicle body is manifested as the vehicle body tilting to the left; if the right wheel gets stuck, the roll angle of the vehicle body is manifested as the vehicle body tilting to the right.

[0056] The direction of suspension height change is analyzed in correspondence with the direction of vehicle body attitude change. Only when the two are consistent is the suspected wheel trapped as the actual wheel trapped, and the specific location of the wheel trapped is determined.

[0057] After completing the wheel positioning, we continue to analyze the degree of vehicle sinking, read the wheel speed changes, suspension height changes, and vehicle posture changes in multiple sampling periods, and analyze whether the same trend of change is maintained.

[0058] If the difference between the wheel speed of the stuck wheel and the other drive wheels persists, and the corresponding suspension height continues to change, while the pitch and roll angles remain in the same direction, it indicates that the vehicle is still in a continuous sinking process. The current sinking state of the vehicle is classified according to the degree of wheel speed deviation, suspension compression, and vehicle body posture deviation.

[0059] The three state indicators of wheel speed deviation, suspension compression, and vehicle body attitude deviation are calculated separately and compared with multiple pre-calibrated threshold intervals.

[0060] The average wheel speed of all drive wheels is calculated based on real-time wheel speed data. The difference between the wheel speed of the stuck wheel and the average wheel speed is calculated, and the ratio of the difference to the average wheel speed is used as the degree of wheel speed deviation. The real-time suspension height of the stuck wheel is obtained and compared with the initial suspension height recorded when the vehicle enters the autonomous traction mode; the height difference between the two is used as the degree of suspension compression. The vehicle pitch angle and roll angle are obtained, and the changes between the current attitude angle and the initial attitude angle when the vehicle enters the autonomous traction mode are calculated. The changes in pitch angle and roll angle are fused to obtain the degree of vehicle attitude deviation.

[0061] The wheel speed deviation is used to reflect the slippage state between the stuck wheel and other drive wheels. When the wheel speed deviation is less than the first wheel speed threshold, the tire is determined to maintain effective adhesion; when the wheel speed deviation is between the first and second wheel speed thresholds, the tire is determined to have slipped; when the wheel speed deviation is greater than the second wheel speed threshold, the tire is determined to have spun freely.

[0062] The suspension compression degree is used to reflect the wheel sinking depth. When the suspension compression degree is less than the first height threshold, the wheel sinking depth is determined to be small. When the suspension compression degree is between the first height threshold and the second height threshold, the wheel is determined to have undergone continuous sinking. When the suspension compression degree is greater than the second height threshold, the wheel is determined to have entered the pit.

[0063] The degree of vehicle attitude deviation is determined by both pitch angle and roll angle, and the larger of the two values ​​is taken as the current attitude deviation index. When the attitude deviation index is less than the first attitude threshold, it indicates that the overall vehicle attitude has changed little; when the attitude deviation index is between the first attitude threshold and the second attitude threshold, it indicates that the vehicle's center of gravity has shifted significantly; when the attitude deviation index is greater than the second attitude threshold, it indicates that the vehicle attitude has been affected by being stuck.

[0064] The overall level of subsidence is determined based on the results of the three indicators, and the subsidence level is output. When the wheel speed deviation, suspension compression, and vehicle body posture deviation are all within the first threshold, it is determined to be a level one subsidence.

[0065] When any two of the three indicators reach the second threshold range, while the remaining indicators do not exceed the second threshold, it is judged as a level two subsidence.

[0066] When all three indicators reach the range corresponding to the second threshold, or when any one indicator exceeds the second threshold and the other two indicators reach the first threshold, it is judged as a level three subsidence.

[0067] The controller outputs the location of the stuck wheel, the current level of vehicle sinking, the vehicle pitch angle, the vehicle roll angle, and the current height data of each suspension, and sends the results to the control module.

[0068] Establish the torque distribution relationship between the corresponding drive wheels according to the vehicle drive mode, and generate the target torque sequence of alternating output of the drive wheels based on the location of the trap wheel.

[0069] The controller continuously reads the roll angle data output by the inertial measurement unit and synchronously controls the air suspension actuators according to the location of the stuck wheel. If the stuck wheel is on the left side of the vehicle, the controller controls the right suspension to gradually rise while controlling the left suspension to gradually lower. If the stuck wheel is on the right side of the vehicle, the controller controls the left suspension to gradually rise while controlling the right suspension to gradually lower. If the stuck wheel is at the front of the vehicle, the rear suspension bears more support. If the stuck wheel is at the rear of the vehicle, the front suspension bears more support. By adjusting the height, the vehicle's center of gravity gradually shifts towards the direction of the non-stuck wheel, reducing the vertical pressure on the stuck wheel.

[0070] After the air suspension completes the height adjustment, it continues to read the data fed back by the air suspension height gauge and compares the fed-back height with the target height. When the actual height of each suspension reaches the target state, it maintains the current height and does not continue to adjust. If the vehicle attitude changes again, it recalculates the new suspension target height and continues to adjust.

[0071] Based on the identified wheel crater location, only the valve core heating device inside the tire corresponding to the crater is activated, while the other tires remain in normal condition. Once activated, the valve core heating device continuously supplies heat to the valve core metal structure, causing the temperature of the gas inside the tire to gradually rise.

[0072] As the temperature of the gas inside the tire continues to rise, the pressure inside the tire changes synchronously. When the pressure inside the tire reaches the valve core release condition, the valve core automatically opens the exhaust channel, and some of the gas inside the tire is slowly discharged through the valve core, causing the pressure inside the tire to gradually decrease. When the tire pressure drops to the target tire pressure, the valve core heating is immediately stopped, and the valve core returns to its normal sealing state.

[0073] As tire pressure decreases, the tire tread creates a larger contact area with the sand, resulting in a more uniform pressure distribution. This allows the tire to cover more sand particles, increasing friction between the tire and the sand, while reducing the pressure per unit area, thus inhibiting the tire from sinking further into the sand.

[0074] As the wheel gradually moves upward along the edge of the sandpit, the tire continuously compacts the loose sand layer in front of it and gradually climbs up using the support surface it forms. When the outer edge of the tire gradually rises above the edge of the sandpit, the wheel begins to resume normal rolling and gradually escapes the original sandpit.

[0075] The system continuously collects data from wheel speed sensors, air suspension altitude gauges, and inertial measurement units, and performs cyclic analysis on the vehicle's current operating status. It focuses on monitoring whether the wheel speed of the stuck wheel continues to approach the wheel speed changes of other drive wheels, while also analyzing whether the vehicle's pitch and roll angles gradually return to stability.

[0076] Once the wheel has completely left the pit, its speed no longer deviates continuously, but instead follows the same pattern as the other drive wheels.

[0077] Since the vehicle has returned to a stable supporting state, the pitch and roll angles no longer change continuously in one direction, but remain stable within the normal driving posture range, and the suspension height also gradually remains constant.

[0078] After confirming that the above status remains consistent for several consecutive sampling cycles, it is determined that the vehicle has successfully escaped the predicament.

[0079] Immediately stop the torque oscillation control of the drive system to restore the drive system to normal power output mode; stop the active height adjustment of the air suspension and save the current height of the four suspensions as the lock-in height after the extrication is completed to the air suspension control unit so that the vehicle continues to maintain the current stable posture; at the same time, turn off the valve core heating module and restore the tire pressure monitoring status to normal.

[0080] The autonomous extrication control mode is deactivated, and the vehicle's normal driving control logic is restored. Subsequently, all sensors continue to maintain real-time monitoring. When the vehicle detects new signs of being stuck again, the autonomous extrication process is restarted.

[0081] Furthermore, this embodiment also provides an off-road vehicle autonomous extrication system based on multi-sensor fusion, including: a judgment module, used to acquire real-time data from wheel speed sensors, air suspension altimeters and inertial measurement units, locate the stuck wheel according to the wheel speed difference, determine the sinking level by combining the vehicle pitch angle and roll angle, and output the position of the stuck wheel and the vehicle attitude information.

[0082] The control module is used to generate a torque oscillation distribution strategy based on the wheel position and sinking level, so that the vehicle body produces periodic pitch oscillations to change the contact state between the wheels and the sand, and at the same time adjusts the height of each suspension in combination with the vehicle body roll angle.

[0083] The heating module is used to activate the tire valve core heating on the side of the wheel sinking according to the sinking level. The gas inside the tire is heated and pressurized through heat conduction and then released to the target tire pressure through the valve core.

[0084] The monitoring module continuously monitors the wheel speed change rate and vehicle attitude angle. When the wheel speed recovers to the average level of the drive wheels and the vehicle pitch angle returns to a stable range, the torque oscillation stops and the current suspension height parameters are locked, thus completing the autonomous extrication of the off-road vehicle from the stalemate.

[0085] This embodiment also provides a computer device applicable to a method for autonomous vehicle extrication from off-road stagnation, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement all or part of the steps of the method described in the above embodiments of the present invention.

[0086] This embodiment also provides a storage medium on which a computer program is stored. When the computer program is executed by a processor, it performs the method in any optional implementation of the above embodiments. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0087] The storage medium proposed in this embodiment and the data storage method proposed in the above embodiments belong to the same inventive concept. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0088] In summary, this invention achieves accurate identification of the position and degree of sinking of the stuck wheels by integrating multi-source sensing information such as wheel speed, air suspension height, and vehicle posture, providing a reliable basis for subsequent extrication control. It coordinates the control of torque oscillation, air suspension center of gravity adjustment, and dynamic tire pressure adjustment to simultaneously optimize the wheel-to-ground contact state, vehicle load distribution, and tire adhesion conditions, effectively improving the ability of the stuck wheels to escape from the ditch. Furthermore, by combining wheel speed change rate and vehicle posture to determine the extrication status in real time, it can promptly terminate control and lock suspension parameters after the vehicle regains stable driving, avoiding continuous intervention that could affect vehicle stability. This improves the success rate, control coordination, and intelligence level of off-road vehicles autonomously escaping from stuck conditions.

[0089] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for autonomous vehicle extrication from an off-road obstacle, characterized in that: include: The system acquires real-time data from wheel speed sensors, air suspension height gauges, and inertial measurement units. It locates the stuck wheel based on wheel speed differences, determines the sinking level by combining the vehicle's pitch and roll angles, and outputs the stuck wheel position and vehicle attitude information. Based on the wheel position and sinking level, a torque oscillation distribution strategy is generated to make the vehicle body produce periodic pitch oscillations to change the contact state between the wheels and the sand, while adjusting the height of each suspension in combination with the vehicle body roll angle. According to the level of sinking, the tire valve core heating on the side of the sinking wheel is activated. The gas inside the tire is heated and pressurized through heat conduction and then released through the valve core to the target tire pressure. The system continuously monitors the wheel speed change rate and vehicle attitude angle. When the speed of the stuck wheel returns to the average level of the drive wheels and the vehicle pitch angle returns to a stable range, the torque oscillation stops and the current suspension height parameters are locked, thus completing the autonomous extrication of the off-road vehicle from the stuck situation.

2. The method for autonomous vehicle extrication from off-road stagnation as described in claim 1, characterized in that: The method of locating the trapped wheel based on wheel speed difference includes: Compare the wheel speeds of each drive wheel, calculate the deviation of each drive wheel from the overall average wheel speed of the drive wheels, and mark a drive wheel as a suspected trap wheel when it continuously exhibits a wheel speed change pattern different from other drive wheels; Read the data from the air suspension height gauge and analyze the height changes at the four suspension positions. If the suspension height at the suspected wheel sinking position continues to decrease, it indicates that the wheel is subjected to a continuous sinking effect. Read the pitch and roll angle data output by the inertial measurement unit. If the front wheels get stuck, the pitch angle is shown as the front of the car tilting downwards. If the rear wheels get stuck, the pitch angle is shown as the rear of the car tilting downwards. If the left wheel gets stuck, the roll angle is shown as the car body tilting to the left. If the right wheel gets stuck, the roll angle is shown as the car body tilting to the right. By analyzing the correspondence between the direction of suspension height change and the direction of vehicle attitude change, when the two are consistent, the suspected wheel trap is confirmed to be an actual wheel trap.

3. The method for autonomous vehicle extrication from an off-road obstacle as described in claim 1, characterized in that: The determination of the subsidence level includes: Calculate the degree of wheel speed deviation, suspension compression, and vehicle attitude deviation; The wheel speed deviation is the ratio of the difference between the wheel speed of the trapped wheel and the average wheel speed of the drive wheel to the average wheel speed; the suspension compression is the difference between the real-time suspension height of the trapped wheel and the initial suspension height; the vehicle attitude deviation is the fusion value of the pitch angle change and the roll angle change between the current attitude angle and the initial attitude angle. When all three indicators are within the first threshold, it is determined to be a level 1 subsidence; when any two of the three indicators reach the second threshold range and the remaining indicators do not exceed the second threshold, it is determined to be a level 2 subsidence; when all three indicators reach the corresponding range of the second threshold or when any one indicator exceeds the second threshold and the other two indicators reach the first threshold, it is determined to be a level 3 subsidence.

4. The method for autonomous vehicle extrication from off-road stagnation as described in claim 1, characterized in that: The generated torque oscillation allocation strategy includes: Based on the vehicle's drive configuration, a torque distribution relationship between the drive wheels is established. A target torque sequence is generated by alternating outputs of the drive wheels according to the location of the stuck wheel. The alternating drive torque creates a periodic torque difference between the drive wheels, causing the vehicle body to oscillate back and forth around the pitch axis. This changes the contact pressure distribution and adhesion state between the stuck wheel and the sand, allowing the stuck wheel to gradually form the support point required for climbing during the oscillation process.

5. The method for autonomous vehicle extrication from off-road stagnation as described in claim 1, characterized in that: The adjustment of each suspension height includes: The direction of suspension height adjustment is determined by the location of the stuck wheel. If the stuck wheel is on the left side of the vehicle, the right suspension is gradually raised while the left suspension is gradually lowered. If the stuck wheel is on the right side of the vehicle, the left suspension is gradually raised while the right suspension is gradually lowered. If the stuck wheel is at the front of the vehicle, the rear suspension provides more support. If the stuck wheel is at the rear of the vehicle, the front suspension provides more support. The system continuously reads the feedback data from the air suspension height gauge, compares the feedback height with the target height, and maintains the current height without further adjustment once the actual height of each suspension reaches the target state. If the vehicle's attitude changes again, the system recalculates the new target suspension height and continues to adjust.

6. The method for autonomous vehicle extrication from off-road stagnation as described in claim 1, characterized in that: The starting wheel side tire valve core heating includes: Based on the determined location of the stuck wheel, only the valve core heating device inside the tire corresponding to the stuck wheel is activated, while the other wheels remain in normal condition; After the valve core heating device is activated, it continuously provides heat to the valve core metal structure, causing the temperature of the gas inside the tire to gradually increase. When the tire pressure reaches the valve core release condition, the valve core automatically opens the exhaust channel, and the air inside the tire is slowly discharged through the valve core, causing the tire pressure to gradually decrease. When the tire pressure drops to the target tire pressure, immediately stop heating the valve core to allow it to return to its normal sealing state.

7. A method for autonomous vehicle extrication from an off-road obstacle as described in claim 1, characterized in that: The process of autonomously extricating a vehicle from an off-road obstacle includes: The system continuously collects data from wheel speed sensors, air suspension altitude gauges, and inertial measurement units to perform cyclical analysis of the vehicle's current operating status. When the wheel speed of the stuck wheel no longer deviates continuously, the vehicle pitch and roll angles no longer change continuously in one direction, and the suspension height gradually remains constant, the vehicle is determined to have successfully escaped the predicament after multiple consecutive sampling cycles confirm that the speed remains consistent. Stop the torque oscillation control of the drive system to restore the drive system to normal power output mode, stop the active height adjustment of the air suspension and save the current height of the four suspensions as the lock-in height after the traction is completed, turn off the valve core heating module and restore the tire pressure monitoring status to normal, and release the autonomous traction control mode to restore the normal driving control logic of the vehicle.

8. An off-road vehicle autonomous extrication system based on multi-sensor fusion, based on the off-road vehicle autonomous extrication method according to any one of claims 1 to 7, characterized in that: include, The judgment module is used to acquire real-time data from wheel speed sensors, air suspension altimeters, and inertial measurement units, locate the stuck wheel based on wheel speed differences, determine the sinking level by combining the vehicle pitch angle and roll angle, and output the stuck wheel position and vehicle attitude information. The control module is used to generate a torque oscillation distribution strategy based on the wheel position and sinking level, so that the vehicle body produces periodic pitch oscillations to change the contact state between the wheels and the sand, and at the same time adjusts the height of each suspension in combination with the vehicle body roll angle. The heating module is used to activate the tire valve core heating on the side of the wheel sinking according to the sinking level. The gas inside the tire is heated and pressurized through heat conduction and then released to the target tire pressure through the valve core. The monitoring module continuously monitors the wheel speed change rate and vehicle attitude angle. When the wheel speed recovers to the average level of the drive wheels and the vehicle pitch angle returns to a stable range, the torque oscillation stops and the current suspension height parameters are locked, thus completing the autonomous extrication of the off-road vehicle from the stalemate.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it implements the steps of the autonomous off-road vehicle extrication method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the steps of the off-road vehicle autonomous extrication method according to any one of claims 1 to 7.

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