Off-road assistance control method, apparatus, device, and storage medium

Abstract

Embodiments of the present disclosure provide an off-road auxiliary control method, device, equipment and storage medium. The method comprises: obtaining desired path point position information; the desired path point position information comprises position information and angle information relative to the vehicle; determining a path tracking mode according to the desired path point position information; and controlling the vehicle according to the path tracking mode. According to the embodiments of the present disclosure, the path tracking mode is determined according to the desired path point position information, and the vehicle is controlled according to the path tracking mode, which can reduce the operation of the driver in a bad road condition, assist in controlling the vehicle to pass safely, improve off-road safety, and thus improve the off-road experience.

Description

Technical Field

[0001] This disclosure relates to the field of off-road assist control for off-road vehicles, and more particularly to an off-road assist control method, device, equipment, and storage medium. Background Technology

[0002] With the increasing popularity of off-road vehicles, accidents frequently occur due to the lack of driving experience among off-road drivers. For example, even experienced off-road drivers cannot maintain complete control of the vehicle when encountering rough roads, potholes, narrow turns, or other challenging conditions. Current technology relies on manual steering control when drivers lack off-road experience or encounter difficult road conditions (rough roads, potholes, narrow turns, etc.), making steering even more difficult. Furthermore, it lacks the ability to automatically activate or deactivate tank turn functionality based on current road conditions when turning on narrow roads, resulting in lower vehicle passability and off-road safety, and a poor off-road experience. Summary of the Invention

[0003] This disclosure provides an off-road assist control method, device, equipment, and storage medium, which can ensure the safe passage of vehicles in harsh road conditions, improve off-road safety, and thus enhance the off-road experience.

[0004] In a first aspect, embodiments of this disclosure provide an off-road assist control method, comprising: acquiring desired path point location information; the desired path point location information including position information and angle information relative to the vehicle; determining a path tracking mode based on the desired path point location information; and controlling the vehicle based on the path tracking mode.

[0005] Secondly, embodiments of this disclosure also provide an off-road assist control device, including: a desired path point location information acquisition module, used to acquire desired path point location information; the desired path point location information includes position information and angle information relative to the vehicle; a path tracking mode determination module, used to determine a path tracking mode based on the desired path point location information; and a control module, used to control the vehicle based on the path tracking mode.

[0006] Thirdly, embodiments of this disclosure also provide an electronic device, the electronic device comprising:

[0007] One or more processors;

[0008] Storage device for storing one or more programs.

[0009] When the one or more programs are executed by the one or more processors, the one or more processors implement the off-road assist control method as described in the embodiments of this disclosure.

[0010] Fourthly, embodiments of this disclosure also provide a storage medium containing computer-executable instructions, which, when executed by a computer processor, are used to perform the off-road assist control method as described in embodiments of this disclosure.

[0011] The technical solution of this disclosure involves acquiring desired path point location information, including position and angle information relative to the vehicle; determining a path tracking mode based on the desired path point location information; and controlling the vehicle according to the path tracking mode. This disclosure, by determining the path tracking mode based on the desired path point location information and controlling the vehicle according to the path tracking mode, can reduce driver intervention in adverse road conditions, assist in controlling the vehicle to pass safely, improve off-road safety, and thus enhance the off-road experience. Attached Figure Description

[0012] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0013] Figure 1 This is a schematic flowchart of the off-road assist control method provided in the embodiments of this disclosure;

[0014] Figure 2 This is a schematic diagram of another off-road assist control method provided in an embodiment of the present invention;

[0015] Figure 3 This is a schematic diagram of the structure of an off-road assist control device provided in an embodiment of the present disclosure;

[0016] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure. Detailed Implementation

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

[0018] It should be understood that the steps described in the method embodiments of this disclosure may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of this disclosure is not limited in this respect.

[0019] The term "comprising" and its variations as used herein are open-ended inclusions, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below.

[0020] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are used only to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0021] It should be noted that the terms "a" and "a plurality of" used in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0022] It is understood that the data involved in this technical solution (including but not limited to the data itself, the acquisition or use of the data) shall comply with the requirements of relevant laws, regulations and related provisions.

[0023] Figure 1 This is a schematic flowchart of the off-road assist control method provided in this embodiment. This embodiment is applicable to situations where off-road vehicles encounter adverse road conditions while driving them, and the method assists in controlling the off-road vehicle's driving. The method can be executed by an off-road assist control device, which can be implemented in the form of software and / or hardware. Optionally, it can be implemented by an electronic device, such as a mobile terminal, a PC, or a server.

[0024] like Figure 1 As shown, the method includes:

[0025] S110. Obtain the location information of the desired path point.

[0026] The desired path point location information includes its position and angle relative to the vehicle. In this embodiment, the desired path point location information can be obtained through a positioning communication device.

[0027] Optionally, obtaining the desired path point location information includes: obtaining a desired path point at set intervals to obtain the desired path point location information.

[0028] The set distance can be 0.5 meters. Specifically, the positioning and communication device collects a desired path point at set intervals until the end of the desired path, at which point all desired path points have been collected. It should be noted that during the collection process, each time a desired path point is collected, the positioning and communication device sends the desired path point to the vehicle's route guidance system so that the vehicle can obtain the desired path point.

[0029] S120. Determine the path tracking mode based on the desired path point location information.

[0030] The path tracking modes include a three-way decoupled path tracking mode and a tank turn-around path tracking mode. In this embodiment, the curvature of the desired path point can be calculated based on the desired path point, the corresponding path tracking mode can be determined based on the curvature of the desired path point, and the vehicle can be controlled to switch to the corresponding path tracking mode in real time to control the vehicle's movement.

[0031] S130, Control the vehicle according to the path tracking mode.

[0032] In this embodiment, control information is determined based on the path tracking mode, and the control execution system executes the corresponding control information to achieve vehicle control.

[0033] Optionally, the path tracking mode is determined based on the desired path point location information, including: for the current desired path point, determining the curvature of the current desired path point based on the current desired path point, the forward adjacent desired path point, and the backward adjacent desired path point; determining the driving curvature corresponding to the maximum steering wheel angle when the vehicle travels to the current desired path point; comparing the curvature of the current desired path point with the driving curvature; if the curvature of the current desired path point is less than or equal to the driving curvature, the determined path tracking mode is a three-way decoupled path tracking mode; the three-way decoupled path tracking mode includes a lateral path tracking sub-mode, a longitudinal path tracking sub-mode, and a vertical path tracking sub-mode; if the curvature of the current desired path point is greater than the driving curvature, the determined path tracking mode is a tank turn-type path tracking mode.

[0034] In this embodiment, for the current desired path point, the curvature of the current desired path point is determined based on the current desired path point, the forward adjacent desired path point, and the backward adjacent desired path point.

[0035] For example, the coordinates of the forward adjacent desired path point are (x0, y0), the coordinates of the current desired path point are (x1, y1), and the coordinates of the backward adjacent desired path point are (x2, y2). The curvature of the current desired path point is calculated using the following formula:

[0036]

[0037] Among them, s 01s is the distance between the forward neighboring desired path point and the current desired path point. 02 s is the distance between the forward adjacent desired path points and the backward adjacent desired path points. 12 K is the distance between the backward neighboring desired path point and the current desired path point. current Let be the curvature of the current desired path point.

[0038] For example, the curvature corresponding to the maximum steering wheel angle can be obtained by the following formula:

[0039]

[0040] Where, δ f_max The maximum front wheel steering angle is given by L, where L is the vehicle wheelbase and K is the maximum front wheel steering angle. max This indicates the maximum curvature that can be achieved based on the front wheel steering angle.

[0041] In this embodiment, if the curvature of the current desired path point is less than or equal to the driving curvature, the determined path tracking mode is a three-way decoupled path tracking mode, that is, the vehicle is controlled in three directions: lateral, longitudinal, and vertical. If the curvature of the current desired path point is greater than the driving curvature, the determined path tracking mode is a tank turn-type path tracking mode.

[0042] Optionally, the lateral path tracking sub-mode includes steering wheel angle information; determining the lateral path tracking sub-mode includes: acquiring the road surface adhesion coefficient in real time through an image processing system; determining a second pre-aiming distance based on the road surface adhesion coefficient and a first pre-aiming distance; wherein the first pre-aiming distance is a preset pre-aiming distance; synthesizing each desired path point into a desired path line; forming a pre-aiming area based on vehicle position information and the second pre-aiming distance; determining the intersection of the pre-aiming area and the desired path line located in front of the vehicle as a pre-aiming point; determining steering wheel angle information based on vehicle position information and the pre-aiming point; correspondingly, controlling the vehicle according to the path tracking mode includes: controlling the steering system to execute the steering wheel angle information to control the vehicle.

[0043] Specifically, road surface image information is acquired through vehicle cameras, the ground type is determined based on the image information, the road surface adhesion coefficient is determined based on the ground surface type, and the second pre-aiming distance is determined based on the road surface adhesion coefficient and the first pre-aiming distance. The second pre-aiming distance can be obtained using the following formula:

[0044]

[0045] Where, k preview L is the road surface adhesion coefficient. base For the first aiming distance in off-road conditions, L preview This is the second aiming distance.

[0046] Specifically, each desired path point is fitted into a desired path line; a pre-aiming region is formed based on the vehicle position information and a second pre-aiming distance; the pre-aiming region can be understood as a circular area, the second pre-aiming distance as the radius of the circle, and the vehicle position information as the center of the circle. After obtaining the pre-aiming region, the intersection point between the pre-aiming region and the desired path line is determined, and the intersection point located in front of the vehicle is taken as the pre-aiming point. Based on the vehicle position information and the pre-aiming point, the steering wheel angle information is calculated through a tracking pre-aiming algorithm. The steering system executes the steering wheel angle information to achieve lateral control of the vehicle under off-road conditions.

[0047] Optionally, the longitudinal path tracking sub-mode includes: driving torque information and braking pressure information; determining the longitudinal path tracking sub-mode includes: acquiring road slope information; the road slope information includes downhill, flat, and uphill; determining driving torque information and / or braking pressure information based on the road slope information; correspondingly, controlling the vehicle according to the path tracking mode includes: controlling the drive system to execute the driving torque information; controlling the braking system to execute the braking pressure information.

[0048] Specifically, firstly, a set speed is determined based on road condition information, and then Model Predictive Control (MPC) is used to control the vehicle to the set speed, which can be between 4 km / h and 12 km / h. Next, road gradient information is determined based on the desired path point; this includes downhill, flat, and uphill sections. Based on this road gradient information, driving torque and / or braking pressure information are determined, and the drive system is controlled to apply the driving torque information, while the braking system is controlled to apply the braking pressure information, thereby achieving longitudinal vehicle control under off-road conditions.

[0049] Optionally, the driving torque information and / or braking pressure information are determined based on the road slope information, including: if the road slope information is downhill or flat, determining the first driving torque information based on the idle torque; and determining the braking pressure information of a single wheel based on the expected slip ratio and the actual slip ratio of a single wheel.

[0050] Optionally, the driving torque information and / or braking pressure information are determined based on the road slope information, including: if the road slope information is uphill, determining the second driving torque information based on the vehicle torque.

[0051] The driving torque information includes first driving torque information and second driving torque information.

[0052] For example, the process of controlling vehicle speed and slip ratio under off-road conditions is as follows:

[0053] The longitudinal dynamics formula for the vehicle is as follows:

[0054]

[0055] Where x represents the longitudinal displacement of the vehicle. For the longitudinal speed of the vehicle, F is the longitudinal acceleration of the vehicle, m is the mass of the vehicle, and F is the longitudinal acceleration of the vehicle. t For the total driving force of the vehicle, F b denoted as the total braking force of the vehicle, and i represents the road gradient information calculated based on the desired path point.

[0056] In order for the vehicle to reach the set speed longitudinally, according to F t -F b The values ​​are calculated, and the MPC algorithm is used for vehicle speed control. Then, the driving torque information and / or braking pressure information are determined based on the road slope information.

[0057] When the vehicle is driving downhill or on a flat road, utilize the vehicle's idle torque T idle The system drives the wheel and generates the first driving torque information. Then, it controls the braking pressure of a single wheel to assist in controlling the wheel slip ratio. That is, it determines the braking pressure information of a single wheel based on the expected slip ratio and the actual slip ratio of the single wheel.

[0058] T drive =T idle

[0059]

[0060]

[0061]

[0062]

[0063] Among them, s expect For the desired slip ratio, s act_fl The actual slip ratio of the left front wheel is s. act_fr The actual slip ratio of the right front wheel is s. act_rl The actual slip ratio of the left rear wheel is s. act_rr K represents the actual slip ratio of the right rear wheel. p K is the proportional control coefficient. d This is the differential control coefficient.

[0064] When the vehicle is traveling uphill, the vehicle torque is used to drive the vehicle, that is, the second driving torque information is determined based on the vehicle torque.

[0065] T drive =(F t -F b )*r

[0066] Finally, the total required torque T is obtained. driveAnd the braking pressure information of a single wheel, where r is the tire radius, P brake_fl ,P brake_fr ,P brake_rl ,P brake_rr The information includes braking pressure data for the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. The four brake cylinders act on the four wheels.

[0067] Optionally, the longitudinal path tracking sub-mode also includes central differential lock locking information, front differential lock locking information, and rear differential lock locking information: Determining the longitudinal path tracking sub-mode includes: determining central differential lock locking information when the actual slip ratio of both wheels on the front axle or both wheels on the rear axle is greater than a set threshold; determining front differential lock locking information when the actual slip ratio of a single wheel on the front axle is greater than a set threshold; and determining rear differential lock locking information when the actual slip ratio of a single wheel on the rear axle is greater than a set threshold. Correspondingly, the vehicle is controlled according to the path tracking mode, including: controlling the transmission system to execute central differential lock locking information, front differential lock locking information, or rear differential lock locking information.

[0068] The set threshold can be 50%. In this embodiment, when the actual slip ratio of both wheels on the front axle is greater than the set threshold, or when the actual slip ratio of both wheels on the rear axle is greater than the set threshold, the central differential lock is engaged, thus determining the central differential lock engagement information. When the actual slip ratio of a single wheel on the front axle is greater than the set threshold, the front differential lock is engaged, thus determining the front differential lock engagement information. When the actual slip ratio of a single wheel on the rear axle is greater than the set threshold, the rear differential lock is engaged, thus determining the rear differential lock engagement information. The central differential lock system in the transmission system engages the central differential lock engagement information, the front differential lock system in the transmission system engages the front differential lock engagement information, and the rear differential lock system in the transmission system engages the rear differential lock engagement information to achieve longitudinal vehicle control under off-road conditions.

[0069] Optionally, the vertical path tracking sub-mode includes suspension extension / retraction information; determining the vertical path tracking sub-mode includes: acquiring the vehicle's roll and pitch angles through vehicle sensors; determining the suspension extension / retraction information based on the roll and pitch angles; correspondingly, controlling the vehicle according to the path tracking mode includes: controlling the air suspension system to execute the suspension extension / retraction information.

[0070] In this embodiment, the vertical path tracking sub-mode is mainly used for vehicle attitude adjustment. It adjusts the vehicle height through the four suspensions to achieve attitude control during roll and pitch maneuvers, thus preventing vehicle rollover. This is achieved by adjusting the roll angle Φ. r The formula for calculating the extension and retraction of the four suspensions using the pitch angle θ is as follows:

[0071] ΔH fl =-k Φ *Φ r -kθ *(θ-i)

[0072] ΔH fr =k Φ *Φ r -k θ *(θ-i)

[0073] ΔH rl =-k Φ *Φ r +k θ *(θ-i)

[0074] ΔH rr =k Φ *Φ r +k θ *(θ-i)

[0075] Where, k Φ Here, k represents the roll control coefficient, i is the road slope information calculated based on the desired path point, and k is the roll control coefficient. θ ΔH is the pitch control factor. fl ,ΔH fr ΔH rl ,ΔH rr The information includes the extension / retraction amounts for the left front suspension, right front suspension, left rear suspension, and right rear suspension, respectively.

[0076] In this embodiment, after calculating the extension and retraction information of the left front suspension, right front suspension, left rear suspension, and right rear suspension, the air suspension system executes the extension and retraction information of the left front suspension, right front suspension, left rear suspension, and right rear suspension respectively to achieve vertical control of the vehicle under off-road conditions.

[0077] Optionally, the tank turn-around path tracking mode includes braking yaw moment information and front wheel steering information; determining the tank turn-around path tracking mode includes: determining the braking yaw moment information based on the desired path point position information and the actual vehicle information; the actual vehicle information includes vehicle position information, vehicle lateral velocity, vehicle heading angle, and vehicle yaw rate; determining the front wheel steering information based on the maximum value of the front wheel steering angle; correspondingly, controlling the vehicle according to the path tracking mode includes: controlling the braking system to execute the braking yaw moment information; controlling the steering system to execute the front wheel steering information.

[0078] Specifically, firstly, the desired path points are synthesized into a desired path line. Based on the desired path line, the desired heading angle is determined. Based on the desired path points, the set speed is determined. Then, based on the desired path position information, desired heading angle, set speed, and actual vehicle information, the lateral position deviation, lateral position deviation rate of change, heading angle deviation, and heading angle deviation rate of change are obtained. Finally, the braking yaw moment information is calculated using the MPC algorithm. The specific formula is as follows:

[0079]

[0080] Among them, e lat This is a lateral positional deviation. This represents the rate of change of lateral positional deviation. ω is the heading angle deviation, 1 / R is the curvature of the expected path point closest to the vehicle, and δ is the heading angle deviation. f_max For the maximum front wheel steering angle, l f l is the distance from the center of mass to the front axle. r V is the distance from the center of gravity to the rear axle, m is the vehicle mass, and V is the mass of the vehicle. x Let I be the vehicle's longitudinal velocity, and C be the vehicle's moment of inertia about the z-axis. f For the front axle slip angle stiffness, C r M is the rear axle slip angle stiffness. b This is to apply braking yaw moment.

[0081] In this embodiment, when the curvature of the current desired path point is greater than the driving curvature, the vehicle can be controlled jointly by determining the front wheel steering information and braking yaw moment information based on the maximum value of the front wheel steering angle. Finally, the braking yaw moment information is converted into braking pressure information using the following formula, enabling the vehicle to execute actions based on the braking pressure information.

[0082]

[0083] Among them, P brake The output brake pressure information is given by B, where B is the rear axle track width, r is the wheel radius, and K is the center radius. brake_ratio It is the ratio coefficient between the braking torque and braking pressure of the braking system.

[0084] In this embodiment, when tracking a U-turn on a narrow off-road road, the braking system is controlled to execute braking pressure information for braking yaw torque, and the steering system is controlled to execute front wheel steering information, thereby increasing the steering performance and lateral stability of the vehicle's lateral control.

[0085] The technical solution of this disclosure involves acquiring desired path point location information, including position and angle information relative to the vehicle; determining a path tracking mode based on the desired path point location information; and controlling the vehicle according to the path tracking mode. This disclosure, by determining the path tracking mode based on the desired path point location information and controlling the vehicle according to the path tracking mode, can reduce driver intervention in adverse road conditions, assist in controlling the vehicle to pass safely, improve off-road safety, and thus enhance the off-road experience.

[0086] Figure 2 This is a schematic diagram of another off-road assist control method provided in an embodiment of the present invention. Figure 2As shown, the desired path point location information is first obtained through the path guidance system. During the path tracking mode determination process, the road surface adhesion coefficient is obtained through the image processing system. The curvature of the current desired path point is determined, along with the driving curvature corresponding to the maximum steering wheel angle when the vehicle reaches the current desired path point. The curvature of the current desired path point is compared with the driving curvature. If the curvature of the current desired path point is less than or equal to the driving curvature, the determined path tracking mode is a three-way decoupled path tracking mode; if the curvature of the current desired path point is greater than the driving curvature, the determined path tracking mode is a tank turn path tracking mode. The three-way decoupled path tracking mode outputs steering wheel angle information (obtained based on the road surface adhesion coefficient), driving torque information, braking pressure information, differential lock locking information, front differential lock locking information, rear differential lock locking information, and suspension extension / retraction information. The steering system executes the steering wheel angle information, the drive system executes the driving torque information, the braking system executes the braking pressure information, the transmission system executes the center differential lock locking information, the front differential lock locking information, or the rear differential lock locking information, and the air suspension system executes the suspension extension / retraction information. The tank turn-type path tracking mode outputs braking pressure information for the braking yaw moment and front wheel steering information. The braking system executes the braking pressure information for the braking yaw moment, and the steering system executes the front wheel steering information. Furthermore, the calculation of curvature and determination of the path tracking mode are both performed by the controller (CDS), which outputs corresponding control information.

[0087] Figure 3 This is a schematic diagram of the structure of an off-road assist control device provided in an embodiment of the present disclosure, as shown below. Figure 3 As shown, the device includes: a desired path point location information acquisition module 210, a path tracking mode determination module 220, and a control module 230;

[0088] The desired path point location information acquisition module 210 is used to acquire desired path point location information; the desired path point location information includes position information and angle information relative to the vehicle.

[0089] The path tracking mode determination module 220 is used to determine the path tracking mode based on the desired path point location information.

[0090] The control module 230 is used to control the vehicle according to the path tracking mode.

[0091] The technical solution of this disclosure involves acquiring desired path point location information through a desired path point location information acquisition module; determining the desired path point location information, including its position and angle relative to the vehicle, through a path tracking mode determination module; determining a path tracking mode based on the desired path point location information through a control module; and controlling the vehicle according to the path tracking mode. This disclosure, by determining the path tracking mode based on the desired path point location information and controlling the vehicle according to the path tracking mode, can reduce driver intervention in adverse road conditions, assist in safely controlling the vehicle to pass through difficult terrain, improve off-road safety, and thus enhance the off-road experience.

[0092] Optionally, the desired path point location information acquisition module is specifically used to: acquire a desired path point at set intervals and obtain the desired path point location information.

[0093] Optionally, the path tracking mode determination module is specifically used for: determining the curvature of the current desired path point based on the current desired path point, the forward adjacent desired path point, and the backward adjacent desired path point; determining the driving curvature corresponding to the maximum steering wheel angle when the vehicle travels to the current desired path point; comparing the curvature of the current desired path point with the driving curvature; if the curvature of the current desired path point is less than or equal to the driving curvature, then the determined path tracking mode is a three-way decoupled path tracking mode; the three-way decoupled path tracking mode includes a lateral path tracking sub-mode, a longitudinal path tracking sub-mode, and a vertical path tracking sub-mode; if the curvature of the current desired path point is greater than the driving curvature, then the determined path tracking mode is a tank turn-type path tracking mode.

[0094] Optionally, the lateral path tracking sub-mode includes steering wheel angle information; optionally, the path tracking mode determination module is further configured to: acquire the road surface adhesion coefficient in real time through an image processing system; determine a second pre-aiming distance based on the road surface adhesion coefficient and a first pre-aiming distance; wherein the first pre-aiming distance is a preset pre-aiming distance; synthesize the desired path points into a desired path line; form a pre-aiming area based on vehicle position information and the second pre-aiming distance; determine the intersection of the pre-aiming area and the desired path line located in front of the vehicle as a pre-aiming point; and determine steering wheel angle information based on the vehicle position information and the pre-aiming point.

[0095] Optionally, the control module is specifically used to: control the steering system to execute the steering wheel angle information in order to control the vehicle.

[0096] Optionally, the longitudinal path tracking sub-mode includes: driving torque information and braking pressure information; optionally, the path tracking mode determination module is further configured to: acquire road slope information; the road slope information includes downhill, flat, and uphill; determine the driving torque information and / or braking pressure information based on the road slope information; optionally, the control module is further configured to: control the drive system to execute the driving torque information; control the braking system to execute the braking pressure information.

[0097] Optionally, the path tracking mode determination module is also used to: determine the first driving torque information based on the idle torque if the road slope information is downhill or flat; and determine the braking pressure information of a single wheel based on the expected slip ratio and the actual slip ratio of a single wheel.

[0098] Optionally, the path tracking mode determination module is also used to: if the road slope information is uphill, determine the second driving torque information based on the vehicle torque.

[0099] Optionally, the longitudinal path tracking sub-mode further includes central differential lock locking information, front differential lock locking information, and rear differential lock locking information. Optionally, the path tracking mode determination module is further configured to: determine central differential lock locking information when the actual slip ratio of both wheels on the front axle or both wheels on the rear axle is greater than a set threshold; determine front differential lock locking information when the actual slip ratio of a single wheel on the front axle is greater than a set threshold; and determine rear differential lock locking information when the actual slip ratio of a single wheel on the rear axle is greater than a set threshold. Optionally, the control module is further configured to: control the transmission system to execute the central differential lock locking information, the front differential lock locking information, or the rear differential lock locking information.

[0100] Optionally, the vertical path tracking sub-mode includes suspension extension / retraction information; optionally, the path tracking mode determination module is further configured to: acquire the vehicle's roll angle and pitch angle through vehicle sensors; determine the suspension extension / retraction information based on the roll angle and pitch angle; optionally, the control module is further configured to: control the air suspension system to execute the suspension extension / retraction information.

[0101] Optionally, the tank turn-around path tracking mode includes braking yaw moment information and front wheel steering information; optionally, the path tracking mode determination module is further configured to: determine the braking yaw moment information based on the desired path point position information and the actual vehicle information; the actual vehicle information includes vehicle position information, vehicle lateral velocity, vehicle heading angle, and vehicle yaw rate; determine the front wheel steering information based on the maximum value of the front wheel steering angle; optionally, the control module is further configured to: control the braking system to execute the braking yaw moment information; and control the steering system to execute the front wheel steering information.

[0102] The off-road assist control device provided in this disclosure can execute the off-road assist control method provided in any embodiment of this disclosure, and has the corresponding functional modules and beneficial effects of the method execution.

[0103] It is worth noting that the various units and modules included in the above-mentioned device are only divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be realized; in addition, the specific names of each functional unit are only for easy differentiation and are not used to limit the protection scope of the embodiments of this disclosure.

[0104] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure. Reference is made below. Figure 4 It illustrates an electronic device suitable for implementing embodiments of the present disclosure (e.g., Figure 4 The diagram below shows the structure of the terminal device or server 500. The terminal device in this embodiment may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), and vehicle terminals (e.g., vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. Figure 4 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of the embodiments disclosed herein.

[0105] like Figure 4 As shown, electronic device 500 may include a processing unit (e.g., central processing unit, graphics processor, etc.) 501, which can perform various appropriate actions and processes according to a program stored in read-only memory (ROM) 502 or a program loaded from storage device 508 into random access memory (RAM) 503. The RAM 503 also stores various programs and data required for the operation of electronic device 500. The processing unit 501, ROM 502, and RAM 503 are interconnected via bus 504. An edit / output (I / O) interface 505 is also connected to bus 504.

[0106] Typically, the following devices can be connected to I / O interface 505: input devices 506 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 507 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 508 including, for example, magnetic tapes, hard disks, etc.; and communication devices 509. Communication device 509 allows electronic device 500 to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 4An electronic device 500 with various devices is shown; however, it should be understood that it is not required to implement or possess all of the devices shown. More or fewer devices may be implemented or possessed alternatively.

[0107] In particular, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 509, or installed from a storage device 508, or installed from a ROM 502. When the computer program is executed by the processing device 501, it performs the functions defined in the methods of embodiments of this disclosure.

[0108] The names of messages or information exchanged between multiple devices in the embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of such messages or information.

[0109] The electronic device provided in this embodiment and the off-road assist control method provided 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.

[0110] This disclosure provides a computer storage medium storing a computer program that, when executed by a processor, implements the off-road assist control method provided in the above embodiments.

[0111] It should be noted that the computer-readable medium described in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in connection with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0112] In some implementations, clients and servers can communicate using any currently known or future-developed network protocol such as HTTP (Hypertext Transfer Protocol) and can interconnect with digital data communication (e.g., communication networks) of any form or medium. Examples of communication networks include local area networks (“LANs”), wide area networks (“WANs”), the Internet (e.g., the Internet of Things), and peer-to-peer networks (e.g., ad hoc peer-to-peer networks), as well as any currently known or future-developed networks.

[0113] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0114] The aforementioned computer-readable medium carries one or more programs that, when executed by the electronic device, cause the electronic device to: acquire desired path point location information; the desired path point location information includes position information and angle information relative to the vehicle; determine a path tracking mode based on the desired path point location information; and control the vehicle based on the path tracking mode.

[0115] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including but not limited to object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0116] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0117] The units described in the embodiments of this disclosure can be implemented in software or in hardware. The name of a unit does not necessarily limit the unit itself; for example, the first acquisition unit can also be described as "a unit that acquires at least two Internet Protocol addresses".

[0118] The functions described above in this document can be performed, at least in part, by one or more hardware logic components. For example, exemplary types of hardware logic components that can be used, without limitation, include: Field Programmable Gate Arrays (FPGAs), Application-Specific Integrated Circuits (ASICs), Application Standard Products (ASSPs), System-on-Chip (SoCs), Complex Programmable Logic Devices (CPLDs), and so on.

[0119] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0120] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

[0121] Furthermore, while the operations are described in a specific order, this should not be construed as requiring these operations to be performed in the specific order shown or in a sequential order. In certain environments, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of this disclosure. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0122] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

Claims

1. An off-road assist control method, characterized in that, include: Obtain the location information of the expected path points; The expected waypoint location information includes position and angle information relative to the vehicle; The path tracking mode is determined based on the desired path point location information; The vehicle is controlled according to the path tracking mode; The step of determining the path tracking mode based on the desired path point location information includes: For the current desired path point, the curvature of the current desired path point is determined based on the current desired path point, the forward adjacent desired path point, and the backward adjacent desired path point. Determine the curvature corresponding to the maximum steering wheel angle when the vehicle reaches the current desired path point; Compare the curvature of the current desired path point with the travel curvature; If the curvature of the current desired path point is less than or equal to the driving curvature, then the determined path tracking mode is a three-way decoupled path tracking mode; the three-way decoupled path tracking mode includes a lateral path tracking sub-mode, a longitudinal path tracking sub-mode, and a vertical path tracking sub-mode. If the curvature of the current desired path point is greater than the driving curvature, then the determined path tracking mode is the tank turn-around path tracking mode. The lateral path tracking sub-mode includes steering wheel angle information; determining the lateral path tracking sub-mode includes: The road surface adhesion coefficient is obtained in real time through an image processing system; The second aiming distance is determined based on the road surface adhesion coefficient and the first aiming distance; wherein, the first aiming distance is a preset aiming distance; Combine the desired path points into a desired path line; A pre-aiming area is formed based on vehicle location information and a second pre-aiming distance; The intersection of the pre-aiming area and the desired path line located in front of the vehicle is determined as the pre-aiming point; The steering wheel angle information is determined based on the vehicle position information and the pre-aiming point; Accordingly, controlling the vehicle according to the path tracking mode includes: The steering system is controlled to execute the steering wheel angle information in order to control the vehicle.

2. The method according to claim 1, characterized in that, Obtain the desired waypoint location information, including: Obtain a desired path point at set intervals to obtain the desired path point location information.

3. The method according to claim 1, characterized in that, The longitudinal path tracking sub-mode includes: driving torque information and braking pressure information; determining the longitudinal path tracking sub-mode includes: Obtain road slope information; the road slope information includes downhill, flat, and uphill. The driving torque information and / or braking pressure information are determined based on the road slope information; Accordingly, controlling the vehicle according to the path tracking mode includes: The control drive system executes the drive torque information; The braking system is controlled to execute the braking pressure information.

4. The method according to claim 3, characterized in that, Determining the driving torque information and / or braking pressure information based on the road slope information includes: If the road slope information is downhill or flat, the first driving torque information is determined based on the idle torque. The braking pressure information for a single wheel is determined based on the expected slip ratio and the actual slip ratio of that wheel.

5. The method according to claim 3, characterized in that, Determining the driving torque information and / or braking pressure information based on the road slope information includes: If the road slope information is uphill, the second driving torque information is determined based on the vehicle torque.

6. The method according to claim 1 or 3, characterized in that, The longitudinal path tracking sub-mode also includes central differential lock locking information, front differential lock locking information, and rear differential lock locking information: Determining the longitudinal path tracking sub-mode includes: When the actual slip ratio of both wheels on the front axle or both wheels on the rear axle is greater than the set threshold, the central differential lock is locked. When the actual slip ratio of a single wheel on the current axle exceeds a set threshold, the front differential lock is engaged. When the actual slip ratio of a single wheel on the rear axle exceeds a set threshold, the rear differential lock is locked. Accordingly, controlling the vehicle according to the path tracking mode includes: The control transmission system executes the locking information of the central differential lock, the locking information of the front differential lock, or the locking information of the rear differential lock.

7. The method according to claim 1, characterized in that, The vertical path tracking sub-mode includes suspension extension / retraction information; Determining the vertical path tracking sub-mode includes: The vehicle's roll and pitch angles are obtained through vehicle sensors; The suspension extension / retraction information is determined based on the roll and pitch angles. Accordingly, controlling the vehicle according to the path tracking mode includes: The air suspension system is controlled to execute the suspension extension / retraction information.

8. The method according to claim 1, characterized in that, The tank turn-around path tracking mode includes braking yaw moment information and front wheel steering information; Determine the tank turning path tracking mode, including: The braking yaw moment information is determined based on the desired path point location information and the actual vehicle information; the actual vehicle information includes vehicle position information, vehicle lateral velocity, vehicle heading angle, and vehicle yaw rate. Determine the front wheel steering information based on the maximum front wheel steering angle; Accordingly, controlling the vehicle according to the path tracking mode includes: The braking system is controlled to execute the braking yaw moment information; The steering system is controlled to execute the front wheel steering information.

9. An off-road assist control device, characterized in that, include: The desired path point location information acquisition module is used to acquire the desired path point location information; The expected waypoint location information includes position and angle information relative to the vehicle; A path tracking mode determination module is used to determine the path tracking mode based on the desired path point location information. A control module is used to control the vehicle according to the path tracking mode; The path tracking mode determination module is specifically used for: for the current desired path point, determining the curvature of the current desired path point based on the current desired path point, the forward adjacent desired path point, and the backward adjacent desired path point; determining the driving curvature corresponding to the maximum steering wheel angle when the vehicle travels to the current desired path point; and comparing the curvature of the current desired path point with the driving curvature. If the curvature of the current desired path point is less than or equal to the driving curvature, the determined path tracking mode is a three-way decoupled path tracking mode; the three-way decoupled path tracking mode includes a lateral path tracking sub-mode, a longitudinal path tracking sub-mode, and a vertical path tracking sub-mode; if the curvature of the current desired path point is greater than the driving curvature, the determined path tracking mode is a tank turn-around path tracking mode. The lateral path tracking sub-mode includes steering wheel angle information; the path tracking mode determination module is further configured to: acquire the road surface adhesion coefficient in real time through an image processing system; determine a second pre-aiming distance based on the road surface adhesion coefficient and a first pre-aiming distance; wherein the first pre-aiming distance is a preset pre-aiming distance; synthesize the desired path points into a desired path line; form a pre-aiming area based on vehicle position information and the second pre-aiming distance; determine the intersection of the pre-aiming area and the desired path line located in front of the vehicle as a pre-aiming point; and determine steering wheel angle information based on the vehicle position information and the pre-aiming point. The control module is specifically used to control the steering system to execute the steering wheel angle information in order to control the vehicle.

10. An electronic device, characterized in that, The electronic device includes: One or more processors; Storage device for storing one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the off-road assist control method as described in any one of claims 1-8.

11. A storage medium containing computer-executable instructions, which, when executed by a computer processor, are used to perform the off-road assist control method as described in any one of claims 1-8.

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