A method, system, device, and medium for steering assistance control

Abstract

This application provides a method, system, device, and medium for steering assist control. The method includes: determining whether to activate the steering assist function based on an acquired target signal; when the steering assist function is activated, determining the target deflection torque for the front axle and the target deflection torque for the rear axle based on the driving terrain; based on the target deflection torque for the front axle, controlling the front axle drive motor to apply a corresponding forward drive torque to the front wheels of the vehicle and a corresponding braking torque to the inner front wheel of the vehicle, thereby controlling the front axle to obtain the target deflection torque; based on the target deflection torque for the rear axle, controlling the rear axle drive motor to apply a corresponding reverse drive torque to the rear wheels of the vehicle and a corresponding braking torque to the outer rear wheel of the vehicle, thereby controlling the rear axle to obtain the target deflection torque. The aim is to reduce the vehicle's turning radius and lower the difficulty of steering.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, specifically to a method, system, device, and medium for steering assist control. Background Technology

[0002] Steering is a basic control function of vehicle control. Currently, the traditional steering control function of vehicles can meet most vehicle operating conditions. However, once the steering of a traditional vehicle is designed and finalized, its minimum turning radius is fixed. When the vehicle is driving on a narrow and winding road, its steering is limited. In a small area of ​​road, the vehicle cannot smoothly complete steering or U-turn actions. Summary of the Invention

[0003] In view of this, embodiments of this application provide a method, system, device, and medium for steering assist control. The aim is to reduce the vehicle's turning radius and decrease the difficulty of steering.

[0004] The first aspect of this application provides a steering assist control method applied to a dual-motor driven vehicle, the vehicle including a braking system capable of independently controlling each wheel, the method comprising:

[0005] Based on the acquired target signal, determine whether to activate the steering assist function;

[0006] When the steering assist function is activated, the target yaw torque for the front axle and the target yaw torque for the rear axle are determined according to the driving terrain.

[0007] Based on the target deflection torque of the front axle, the front axle drive motor is controlled to apply a corresponding positive drive torque to the front wheels of the vehicle and a corresponding braking torque to the steering inner front wheels of the vehicle, so as to control the front axle of the vehicle to obtain the target deflection torque of the front axle.

[0008] Based on the target deflection torque of the rear axle, the rear axle drive motor is controlled to apply a corresponding reverse drive torque to the rear wheels of the vehicle and a corresponding braking torque to the outer rear wheel of the vehicle, so as to control the rear axle of the vehicle to obtain the target deflection torque of the rear axle.

[0009] Optionally, the method further includes:

[0010] The yaw rate of the vehicle is determined based on the acquired yaw rate signal of the vehicle.

[0011] The yaw rate is compared with the first target threshold and the second target threshold respectively to obtain the first comparison result;

[0012] Based on the first comparison result, the torque applied to the wheels of the vehicle is adjusted to correct the yaw rate of the vehicle.

[0013] Optionally, based on the first comparison result, adjusting the torque applied to the wheels of the vehicle to correct the yaw rate of the vehicle includes:

[0014] When the first comparison result indicates that the yaw rate is less than or equal to the first target threshold, increase the positive drive torque of the outer front wheel and increase the braking torque of the inner front wheel, and / or increase the reverse drive torque of the inner rear wheel and increase the braking torque of the outer rear wheel.

[0015] If the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, reduce the positive drive torque of the outer front wheel and reduce the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and reduce the braking torque of the outer rear wheel.

[0016] Optionally, before reducing the positive drive torque of the outer front wheel and the braking torque of the inner front wheel, and / or reducing the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel, when the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, the method further includes:

[0017] If the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, the instability yaw rate is determined based on the vehicle speed and steering wheel angle.

[0018] The yaw rate is compared with the instability yaw rate to obtain a second comparison result;

[0019] If the second comparison result indicates that the yaw rate is greater than or equal to the instability yaw rate, control the application of positive driving torque and the termination of braking torque to all wheels of the vehicle.

[0020] If the second comparison result indicates that the yaw rate is less than the instability yaw rate, the following steps are performed: reduce the positive drive torque of the outer front wheel and reduce the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and reduce the braking torque of the outer rear wheel.

[0021] Optionally, the method further includes:

[0022] Based on the driving terrain, determine the target slip ratio corresponding to each wheel of the vehicle;

[0023] The slip ratio of each wheel of the vehicle is compared with its corresponding target slip ratio to obtain a third comparison result;

[0024] Based on the third comparison result, the torque applied to the wheels of the vehicle is adjusted to correct the slip ratio of each wheel of the vehicle.

[0025] Optionally, based on the third comparison result, the torque applied to the wheels of the vehicle is adjusted to correct the slip ratio of each wheel of the vehicle, including:

[0026] If the slip ratio of the outer front wheel is less than its corresponding target slip ratio, the positive drive torque of the outer front wheel is increased.

[0027] If the slip ratio of the outer front wheel is greater than its corresponding target slip ratio, the positive drive torque of the outer front wheel is reduced.

[0028] If the slip ratio of the inner front wheel is less than its corresponding target slip ratio, the positive drive torque of the inner front wheel is increased or the braking torque of the inner front wheel is decreased in the third comparison result.

[0029] If the third comparison result includes a slip ratio of the inner front wheel that is greater than its corresponding target slip ratio, the positive drive torque of the inner front wheel is reduced or the braking torque of the inner front wheel is increased.

[0030] If the slip ratio of the inner rear wheel is less than its corresponding target slip ratio, the reverse drive torque of the inner rear wheel is increased.

[0031] If the slip ratio of the inner rear wheel is greater than its corresponding target slip ratio, the reverse drive torque of the inner rear wheel is reduced.

[0032] If the slip ratio of the outer rear wheel is less than its corresponding target slip ratio, the reverse drive torque of the outer rear wheel is increased or the braking torque of the outer rear wheel is decreased in the third comparison result.

[0033] If the third comparison result includes a slip ratio of the outer rear wheel that is greater than its corresponding target slip ratio, the reverse drive torque of the outer rear wheel is reduced or the braking torque of the outer rear wheel is increased.

[0034] Optionally, based on the driving terrain, the target yaw torque for the front axle and the target yaw torque for the rear axle are determined, including:

[0035] Obtain a pre-constructed first correspondence, which includes the correspondence between driving terrain and target deflection torque, wherein the target deflection torque includes front axle target deflection torque and rear axle target deflection torque;

[0036] Based on the vehicle's driving terrain and the first correspondence, the target deflection torque of the front axle and the target deflection torque of the rear axle corresponding to the driving terrain are determined.

[0037] Optionally, based on the driving terrain, determine individual target slip ratios corresponding to each wheel of the vehicle, including:

[0038] Obtain a pre-constructed second correspondence, which includes the correspondence between the driving terrain and the target slip ratio of the wheels, wherein the target slip ratio of the wheels includes the target slip ratio of the left front wheel, the target slip ratio of the right front wheel, the target slip ratio of the left rear wheel, and the target slip ratio of the right rear wheel;

[0039] Based on the driving terrain of the vehicle and the second correspondence, the target slip ratio of each wheel corresponding to the driving terrain is determined.

[0040] Optionally, the method further includes:

[0041] During the adjustment of the torque applied to the wheels of the vehicle, the front axle deflection torque and the rear axle deflection torque of the vehicle are monitored.

[0042] The front axle deflection torque obtained by monitoring is compared with the upper limit of the torque range of the determined front axle target deflection torque, and the rear axle deflection torque obtained by monitoring is compared with the upper limit of the torque range of the determined rear axle target deflection torque to obtain a fourth comparison result.

[0043] Based on the fourth comparison result, determine whether to end the adjustment of the applied torque.

[0044] Optionally, based on the fourth comparison result, determining whether to end the adjustment of the applied torque includes:

[0045] If the fourth comparison result indicates that the deviation between the front axle deflection torque and the upper limit of the torque range of the target front axle deflection torque is within a first preset range, and / or the deviation between the rear axle deflection torque and the upper limit of the torque range of the target rear axle deflection torque is within a second preset range, the adjustment of the applied torque ends.

[0046] Optionally, the target signal includes: a steering assist function switch signal, a steering wheel angle signal, and an accelerator pedal signal.

[0047] A second aspect of this application provides a steering assist control system, the system comprising:

[0048] The signal acquisition module is used to acquire the target signal;

[0049] The function control module is used to determine whether to activate the steering assist function based on the acquired target signal;

[0050] The torque determination module is used to determine the target deflection torque of the front axle and the target deflection torque of the rear axle based on the driving terrain when the steering assist function is activated.

[0051] The first control module is used to control the front axle drive motor to apply a corresponding positive drive torque to the front wheels of the vehicle and a corresponding braking torque to the steering inner front wheels of the vehicle according to the target deflection torque of the front axle, so as to control the front axle of the vehicle to obtain the target deflection torque of the front axle.

[0052] The second control module is used to control the rear axle drive motor to apply a corresponding reverse drive torque to the rear wheels of the vehicle and a corresponding braking torque to the outer rear wheel of the vehicle, based on the target deflection torque of the rear axle, so as to control the rear axle of the vehicle to obtain the target deflection torque of the rear axle.

[0053] Optionally, the system further includes:

[0054] The yaw rate determination module is used to determine the yaw rate of the vehicle based on the acquired yaw rate signal of the vehicle.

[0055] The first comparison module is used to compare the yaw rate with a first target threshold and a second target threshold respectively to obtain a first comparison result;

[0056] The first correction module is used to adjust the torque applied to the wheels of the vehicle based on the first comparison result, so as to correct the yaw rate of the vehicle.

[0057] Optionally, the first correction module includes:

[0058] The first torque adjustment module is used to increase the positive drive torque of the outer front wheel and the braking torque of the inner front wheel when the first comparison result indicates that the yaw rate is less than or equal to the first target threshold, and / or increase the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel.

[0059] The second torque adjustment module is used to reduce the positive drive torque of the outer front wheel and the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel when the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold.

[0060] Optionally, the system further includes:

[0061] The instability yaw rate determination module is used to determine the instability yaw rate based on the vehicle speed and steering wheel angle when the first comparison result indicates that the yaw rate is greater than or equal to a second target threshold.

[0062] The second comparison module is used to compare the yaw rate with the instability yaw rate to obtain a second comparison result;

[0063] The third torque adjustment module is used to control the application of positive driving torque and the termination of braking torque to all wheels of the vehicle when the second comparison result indicates that the yaw rate is greater than or equal to the instability yaw rate.

[0064] The fourth torque adjustment module is used to control the execution of the second torque adjustment module when the second comparison result indicates that the yaw rate is less than the instability yaw rate.

[0065] A third aspect of this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements a steering assistance control method as described in the first aspect of this application.

[0066] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements a steering assistance control method as described in the first aspect of this application.

[0067] The steering assist control method provided in this application has the following advantages:

[0068] This application provides a steering assist control method applied to a dual-motor driven vehicle, where each wheel is braked by an independent braking system. First, based on an acquired target signal, it is determined whether to activate the steering assist function. If the steering assist function is activated, target deflection torques for the front axle and rear axle are determined based on the driving terrain. Based on the determined front axle target deflection torque, the front axle drive motor is controlled to apply a corresponding forward drive torque to the front wheels of the vehicle, while simultaneously applying a corresponding braking torque to the inner front wheel, thereby controlling the front axle to obtain a deflection torque equal to the target front axle deflection torque. Based on the determined rear axle target deflection torque, the rear axle drive motor is controlled to apply a corresponding reverse drive torque to the rear wheels of the vehicle, while simultaneously applying a corresponding braking torque to the outer rear wheel, thereby controlling the rear axle to obtain a deflection torque equal to the target rear axle deflection torque. Therefore, the steering assist control method provided in this application provides for vehicle steering control. By applying a forward driving torque to the front wheels of the vehicle, and simultaneously applying a certain braking torque to the inner front wheel (at this time, the inner front wheel is still rotating, but due to the presence of braking torque, its driving torque will be less than that of the outer front wheel), the driving torque on the outer front wheel is greater than that on the inner front wheel, resulting in a greater driving force on the outer front wheel than on the inner front wheel. This ultimately generates a yaw torque on the front axle of the vehicle. This yaw torque is transmitted to the vehicle body, causing the vehicle body to produce a yaw tendency in the same direction as the steering (e.g., turning right results in a rightward yaw tendency; turning left results in a leftward yaw tendency). When this yaw torque is large enough, the vehicle can undergo a yaw movement in the same direction as the steering, thereby accelerating the vehicle's steering and reducing the turning radius. By applying a rearward driving torque to the rear wheels of the vehicle, while simultaneously applying a certain braking torque to the outer rear wheel (which is still rotating, but its driving torque is less than that of the inner rear wheel due to the braking torque), the driving force generated on the inner rear wheel is greater than that on the outer rear wheel. This creates a yaw torque on the rear axle, which is transmitted to the vehicle body, causing it to yaw in the same direction as the steering (e.g., yaw to the right when turning right, and yaw to the left when turning left). When this yaw torque is large enough, the vehicle can yaw in the same direction as the steering, thus accelerating the vehicle's turn and reducing the turning radius. When the yaw torque generated by the front axle and the rear axle work together, a larger resultant torque is generated, further enhancing the effect of reducing the vehicle's turning radius and making the vehicle more agile. Attached Figure Description

[0069] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0070] Figure 1 A flowchart illustrating a steering assist control method according to one embodiment of this application;

[0071] Figure 2 This is a schematic diagram illustrating the effect of controlling a vehicle to steer in a steering assist control method according to one embodiment of this application;

[0072] Figure 3 This is a schematic diagram illustrating another effect of controlling the vehicle to steer in a steering assist control method according to one embodiment of this application;

[0073] Figure 4 This is a schematic diagram illustrating a steering assist control system according to one embodiment of this application. Detailed Implementation

[0074] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0075] refer to Figure 1 , Figure 1 This is a schematic diagram illustrating a steering assist control method according to one embodiment of this application. Figure 1 As shown, the steering assist control method provided in this application is applied to a dual-motor driven vehicle, which includes a braking system capable of independently controlling each wheel. The steering assist control method in this embodiment includes:

[0076] Step S1: Based on the acquired target signal, determine whether to activate the steering assist function.

[0077] In this embodiment, the steering assist control method provided in this application is applied to a dual-motor driven vehicle. The dual motors of the vehicle include a front axle drive motor and a rear axle drive motor. The front axle drive motor drives both front wheels of the vehicle simultaneously, meaning that the two front wheels share one front axle drive motor for driving. The rear axle drive motor drives both rear wheels of the vehicle simultaneously, meaning that the two rear wheels share one rear axle drive motor for driving. The vehicle also includes a braking system capable of independently controlling each wheel.

[0078] In this embodiment, a target signal from the vehicle is first received. Based on the received target signal, a decision is made on whether to activate the steering assist function. The target signal includes, but is not limited to, a steering assist function switch signal, a steering wheel angle signal, and an accelerator pedal signal.

[0079] In this embodiment, when the target signals include a steering assist function switch signal, a steering wheel angle signal, and an accelerator pedal signal, one possible implementation of step S1 is as follows: determining whether an activation signal for the steering assist function control switch on the vehicle is received, determining whether the received current steering wheel angle signal of the vehicle is greater than a set threshold, and determining whether the current accelerator pedal signal is in a depressed state; when it is determined that an activation signal for the steering assist function control switch on the vehicle is received, the received current steering wheel angle signal of the vehicle is greater than the set threshold, and the received current accelerator pedal signal is in a depressed state, the vehicle's steering assist function is activated.

[0080] Step S2: With the steering assist function activated, determine the target deflection torque for the front axle and the target deflection torque for the rear axle based on the driving terrain.

[0081] In this embodiment, when the steering assist function is activated, it indicates that the vehicle will use this function for steering assistance control. At this time, based on the current driving terrain, a corresponding target deflection torque for the front axle and a target deflection torque for the rear axle are determined. The target deflection torque for the front axle is the expected deflection torque that the vehicle's front axle can achieve when driving on this terrain, and the target deflection torque for the rear axle is the expected deflection torque that the vehicle's rear axle can achieve when driving on this terrain.

[0082] Step S3: Based on the target deflection torque of the front axle, control the front axle drive motor to apply a corresponding positive drive torque to the front wheels of the vehicle and a corresponding braking torque to the steering inner front wheels of the vehicle, so as to control the front axle of the vehicle to obtain the target deflection torque of the front axle.

[0083] In this embodiment, based on the determined front axle target deflection torque, the vehicle's front axle drive motor is controlled to apply a corresponding positive drive torque to the vehicle's front wheels, while simultaneously applying a corresponding braking torque to the vehicle's inner steering front wheels, so that the vehicle's front axle obtains a deflection torque of the same magnitude as the front axle target deflection torque in the direction of vehicle steering.

[0084] For example, such as Figure 2 As shown, the target deflection torque of the vehicle's front axle is determined to be M1. Given that the vehicle is currently turning left, the front axle drive motor is controlled to apply a corresponding positive drive torque to the front wheels of the vehicle, while simultaneously applying a corresponding braking torque to the inner front wheel (the left front wheel). This ensures that the front axle receives a deflection torque equal to the target deflection torque M1, which is the same magnitude as the vehicle's turning direction (leftward). Figure 3 As shown, the target deflection torque of the vehicle's front axle is determined to be M1. When the vehicle is currently turning right, the front axle drive motor of the vehicle is controlled to apply the corresponding positive drive torque to the front wheel of the vehicle, and at the same time, the corresponding braking torque is applied to the inner front wheel of the vehicle (that is, the right front wheel of the vehicle), so that the front axle of the vehicle obtains a deflection torque of the same magnitude as the target deflection torque M1 of the front axle, which is the same as the direction of the vehicle's turn (that is, the right direction).

[0085] Step S4: Based on the target deflection torque of the rear axle, control the rear axle drive motor to apply a corresponding reverse drive torque to the rear wheels of the vehicle and a corresponding braking torque to the outer rear wheel of the vehicle, so as to control the rear axle of the vehicle to obtain the target deflection torque of the rear axle.

[0086] In this embodiment, based on the determined target deflection torque of the rear axle, the rear axle drive motor of the vehicle is controlled to apply a corresponding reverse drive torque (the drive torque that controls the vehicle to move in the opposite direction of forward movement) to the rear wheels of the vehicle, while applying a corresponding braking torque to the outer rear wheel of the vehicle, so that the rear axle of the vehicle obtains a deflection torque of the same magnitude as the target deflection torque of the rear axle in the direction of vehicle steering.

[0087] For example, such as Figure 2 As shown, the target deflection torque of the vehicle's rear axle is determined to be M2. Given that the vehicle is currently turning left, the rear axle drive motor is controlled to apply a corresponding reverse drive torque to the rear wheels, while simultaneously applying a corresponding braking torque to the outer rear wheel (the right rear wheel). This ensures that the rear axle receives a deflection torque equal to the target deflection torque M2, which is the same magnitude as the vehicle's turning direction (leftward). Figure 3As shown, when the target torque for the rear axle deflection of the vehicle is determined to be M2, and when the vehicle is currently turning to the right, the rear axle drive motor of the vehicle is controlled to apply a corresponding reverse drive torque to the rear wheel of the vehicle, and at the same time, a corresponding braking torque is applied to the outer rear wheel of the vehicle (that is, the left rear wheel of the vehicle), so that the rear axle of the vehicle obtains a deflection torque of the same magnitude as the target deflection torque M2 of the rear axle, which is the same as the direction of the vehicle's turn (that is, the right direction).

[0088] This application provides a steering assist control method applied to a dual-motor driven vehicle, where each wheel is braked by an independent braking system. First, based on an acquired target signal, it is determined whether to activate the steering assist function. If the steering assist function is activated, target deflection torques for the front axle and rear axle are determined based on the driving terrain. Based on the determined front axle target deflection torque, the front axle drive motor is controlled to apply a corresponding forward drive torque to the front wheels of the vehicle, while simultaneously applying a corresponding braking torque to the inner front wheel, thereby controlling the front axle to obtain a deflection torque equal to the target front axle deflection torque. Based on the determined rear axle target deflection torque, the rear axle drive motor is controlled to apply a corresponding reverse drive torque to the rear wheels of the vehicle, while simultaneously applying a corresponding braking torque to the outer rear wheel, thereby controlling the rear axle to obtain a deflection torque equal to the target rear axle deflection torque. Therefore, the steering assist control method provided in this application provides for vehicle steering control. By applying a forward driving torque to the front wheels of the vehicle, and simultaneously applying a certain braking torque to the inner front wheel (at this time, the inner front wheel is still rotating, but due to the presence of braking torque, its driving torque will be less than that of the outer front wheel), the driving torque on the outer front wheel is greater than that on the inner front wheel, resulting in a greater driving force on the outer front wheel than on the inner front wheel. This ultimately generates a yaw torque on the front axle of the vehicle. This yaw torque is transmitted to the vehicle body, causing the vehicle body to produce a yaw tendency in the same direction as the steering (e.g., turning right results in a rightward yaw tendency; turning left results in a leftward yaw tendency). When this yaw torque is large enough, the vehicle can undergo a yaw movement in the same direction as the steering, thereby accelerating the vehicle's steering and reducing the turning radius. By applying a rearward driving torque to the rear wheels of the vehicle, while simultaneously applying a certain braking torque to the outer rear wheel (which is still rotating, but its driving torque is less than that of the inner rear wheel due to the braking torque), the driving force generated on the inner rear wheel is greater than that on the outer rear wheel. This creates a yaw torque on the rear axle, which is transmitted to the vehicle body, causing it to yaw in the same direction as the steering (e.g., yaw to the right when turning right, and yaw to the left when turning left). When this yaw torque is large enough, the vehicle can yaw in the same direction as the steering, thus accelerating the vehicle's turn and reducing the turning radius. When the yaw torque generated by the front axle and the rear axle work together, a larger resultant torque is generated, further enhancing the effect of reducing the vehicle's turning radius and making the vehicle more agile.

[0089] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. In this steering assist control method, step S2 may include steps S21 to S22:

[0090] Step S21: Obtain a pre-constructed first correspondence, which includes the correspondence between driving terrain and target deflection torque, and the target deflection torque includes front axle target deflection torque and rear axle target deflection torque.

[0091] In this embodiment, due to the varying adhesion of the ground on different terrains, the same yaw torque applied to the vehicle corresponds to different degrees of vehicle deflection for different terrains. Therefore, to ensure that the steering assist control method provided in this application performs well in minimizing the turning radius under various driving terrain scenarios, this application pre-constructs corresponding front axle target yaw torque and rear axle target yaw torque for different driving terrains. That is, each driving terrain has a matching front axle target yaw torque and a matching rear axle target yaw torque, so that the vehicle performs well in minimizing the turning radius when turning under various terrains. Specifically: a first correspondence is pre-constructed, which includes the correspondence between driving terrain and target yaw torque. The target yaw torque includes front axle target yaw torque and rear axle target yaw torque, that is, each driving terrain has a matching front axle target yaw torque and a matching rear axle target yaw torque. First, the pre-constructed first correspondence is obtained.

[0092] Step S22: Based on the vehicle's driving terrain and the first correspondence, determine the front axle target deflection torque and rear axle target deflection torque corresponding to the driving terrain.

[0093] In this embodiment, after obtaining the pre-constructed first correspondence, the driving terrain of the current vehicle is determined. Then, based on the driving terrain and the first correspondence, the target deflection torque of the front axle and the target deflection torque of the rear axle corresponding to the driving terrain in the first correspondence are determined. The driving terrain includes, but is not limited to, snow, mud, sand, and concrete. The method for determining the driving terrain can be selected by the user through the control interface, or it can be determined based on the analysis of information collected by various sensors of the vehicle; no specific limitation is made here.

[0094] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. This steering assist control method further includes steps S5 to S7:

[0095] Step S5: Determine the yaw rate of the vehicle based on the acquired yaw rate signal.

[0096] In this embodiment, due to the diverse scenarios in which vehicle steering is controlled, various unexpected situations may arise. To prevent safety issues and ensure the vehicle's steering control achieves its intended goals during steering assist function activation, this application monitors the vehicle's yaw rate in real time during steering assist function activation. Based on the degree of yaw, the vehicle's steering control is corrected to avoid safety problems and ensure the steering control achieves its intended goals. Specifically, during steering assist function activation, the vehicle's yaw rate signal is acquired, and the corresponding yaw rate is determined based on the received signal.

[0097] Step S6: Compare the yaw rate with the first target threshold and the second target threshold respectively to obtain the first comparison result.

[0098] In this embodiment, the determined yaw rate of the vehicle is compared with a first target threshold and a second target threshold to obtain a corresponding first comparison result. The first and second target thresholds can be set according to the actual scenario and / or the vehicle model, etc., and are not specifically limited here. The second target threshold is greater than the first target threshold.

[0099] Step S7: Based on the first comparison result, adjust the torque applied to the wheels of the vehicle to correct the yaw rate of the vehicle.

[0100] In this embodiment, after determining the first comparison result that characterizes the relationship between the current actual yaw rate of the vehicle and the set first target threshold and second target threshold, the torque applied to the wheels of the vehicle (including the driving torque and / or braking torque applied to the wheels of the vehicle) is adjusted based on the first comparison result to correct the yaw rate of the vehicle, thereby preventing safety problems of the vehicle and enabling the steering control of the vehicle to achieve the predetermined target.

[0101] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. In this steering assist control method, step S7 may include steps S71 to S72:

[0102] Step S71: If the first comparison result indicates that the yaw rate is less than or equal to the first target threshold, increase the positive drive torque of the outer front wheel and increase the braking torque of the inner front wheel, and / or increase the reverse drive torque of the inner rear wheel and increase the braking torque of the outer rear wheel.

[0103] In this embodiment, if the obtained first comparison result indicates that the vehicle's current actual yaw rate is less than or equal to a first target threshold, it indicates that the vehicle's yaw rate has not reached the predetermined target. At this time, this application increases the vehicle's yaw rate by increasing the positive drive torque of the vehicle's outer front steering wheel and increasing the braking torque of the vehicle's inner front steering wheel, thereby bringing the vehicle's yaw rate to or closer to the predetermined target. Simultaneously, in another embodiment: this application increases the vehicle's yaw rate by increasing the reverse drive torque of the vehicle's inner rear steering wheel and increasing the braking torque of the vehicle's outer rear steering wheel, thereby bringing the vehicle's yaw rate to or closer to the predetermined target. Simultaneously, in another embodiment: this application increases the vehicle's yaw rate by increasing the positive drive torque of the vehicle's outer front steering wheel and increasing the braking torque of the vehicle's inner front steering wheel, and by increasing the reverse drive torque of the vehicle's inner rear steering wheel and increasing the braking torque of the vehicle's outer rear steering wheel, thereby bringing the vehicle's yaw rate to the predetermined target.

[0104] Step S72: If the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, reduce the positive drive torque of the outer front wheel and reduce the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and reduce the braking torque of the outer rear wheel.

[0105] In this embodiment, if the obtained first comparison result indicates that the vehicle's current actual yaw rate is greater than or equal to the second target threshold, it indicates that the vehicle's yaw rate exceeds the predetermined target. At this time, this application reduces the vehicle's yaw rate by decreasing the positive drive torque of the vehicle's outer front steering wheel and decreasing the braking torque of the vehicle's inner front steering wheel, thereby bringing the vehicle's yaw rate to or closer to the predetermined target. Simultaneously, in another embodiment: this application reduces the vehicle's yaw rate by decreasing the reverse drive torque of the inner rear steering wheel and decreasing the braking torque of the outer rear steering wheel, thereby bringing the vehicle's yaw rate to or closer to the predetermined target. Simultaneously, in another embodiment: this application reduces the vehicle's yaw rate by decreasing the positive drive torque of the vehicle's outer front steering wheel and decreasing the braking torque of the vehicle's inner front steering wheel, and by decreasing the reverse drive torque of the inner rear steering wheel and decreasing the braking torque of the outer rear steering wheel, thereby bringing the vehicle's yaw rate to the predetermined target.

[0106] In this embodiment, if the obtained first comparison result indicates that the actual yaw rate of the vehicle is between the first target threshold and the second target threshold, it indicates that the yaw rate of the vehicle has reached the predetermined target, and the current control state of the vehicle is maintained.

[0107] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. In this steering assist control method, before step S72, the method further includes:

[0108] Step S0721: If the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, the instability yaw rate is determined based on the vehicle speed and steering wheel angle.

[0109] In this embodiment, to prevent vehicle instability caused by excessive yaw rate during steering control via steering assist function, this application, after determining that the first comparison result indicates that the actual yaw rate of the vehicle is greater than or equal to the second target threshold, determines an instability yaw rate corresponding to the current vehicle speed and the current steering wheel angle.

[0110] Step S0722: Compare the yaw rate with the instability yaw rate to obtain a second comparison result.

[0111] In this embodiment, the determined instability yaw rate corresponding to the current state of the vehicle is then compared with the actual yaw rate of the vehicle to obtain a corresponding second comparison result.

[0112] Step S0723: If the second comparison result indicates that the yaw rate is greater than or equal to the instability yaw rate, control the application of positive driving torque and the termination of braking torque to all wheels of the vehicle.

[0113] In this embodiment, if the second comparison result indicates that the actual yaw rate of the vehicle is greater than or equal to the determined instability yaw rate, it indicates that the vehicle is at risk of instability. At this time, the vehicle is controlled to turn off the steering assist function, and the vehicle is controlled to apply positive driving torque to each wheel of the vehicle normally and then stop applying braking torque to the wheel.

[0114] Step S0724: If the second comparison result indicates that the yaw rate is less than the instability yaw rate, proceed to step S72.

[0115] In this embodiment, if the second comparison result indicates that the actual yaw rate of the vehicle is less than the determined instability yaw rate, it indicates that the vehicle is not at risk of instability. At this time, step S72 is executed, which means reducing the positive drive torque of the outer front wheel and the braking torque of the inner front wheel, and / or reducing the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel.

[0116] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. This steering assist control method further includes steps S8 to S10:

[0117] Step S8: Determine the target slip ratio corresponding to each wheel of the vehicle based on the driving terrain.

[0118] In this embodiment, since there are various scenarios for controlling the vehicle to steer, and various emergencies may occur in different scenarios, in order to prevent the vehicle from having safety problems or the vehicle's steering control from failing to achieve the predetermined goal during the steering control process with the steering assist function activated, this application monitors the slip ratio of each wheel of the vehicle in real time during the steering control process with the steering assist function, and corrects the vehicle's steering control according to the slip ratio of each wheel of the vehicle, so as to avoid the vehicle from having safety problems and to make the vehicle's steering control achieve the predetermined goal.

[0119] In this embodiment, based on the driving terrain of the current vehicle, a target slip ratio corresponding to the left front wheel of the vehicle, a target slip ratio corresponding to the right front wheel of the vehicle, a target slip ratio corresponding to the left rear wheel of the vehicle, and a target slip ratio corresponding to the right rear wheel of the vehicle are determined to match the driving terrain.

[0120] Step S9: Compare the slip ratio of each wheel of the vehicle with its corresponding target slip ratio to obtain a third comparison result.

[0121] In this embodiment, the slip ratios of the vehicle's current left front wheel, right front wheel, left rear wheel, and right rear wheel are obtained. Then, the slip ratio of the vehicle's current left front wheel is compared with the target slip ratio corresponding to the vehicle's left front wheel determined in step S8 to obtain a comparison result. Similarly, the slip ratio of the vehicle's current right front wheel is compared with the target slip ratio corresponding to the vehicle's right front wheel determined in step S8 to obtain a comparison result. The slip ratio of the vehicle's current left rear wheel is compared with the target slip ratio corresponding to the vehicle's left rear wheel determined in step S8 to obtain a comparison result. Finally, the slip ratio of the vehicle's current right rear wheel is compared with the target slip ratio corresponding to the vehicle's right rear wheel determined in step S8 to obtain a comparison result. Thus, a total third comparison result is obtained.

[0122] Step S10: Based on the third comparison result, adjust the torque applied to the wheels of the vehicle to correct the slip ratio of each wheel of the vehicle.

[0123] In this embodiment, based on the third comparison result, the torque applied to the vehicle's wheels (including the driving torque and / or braking torque applied to the vehicle's wheels) is adjusted to correct the vehicle's wheel slip ratio, thereby preventing vehicle safety issues and enabling the vehicle's steering control to achieve the predetermined goal.

[0124] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. In this steering assist control method, step S10 may include steps S101 to S108:

[0125] Step S101: If the third comparison result includes the slip ratio of the outer front wheel being less than its corresponding target slip ratio, increase the positive drive torque of the outer front wheel.

[0126] In this embodiment, the obtained third comparison result will include four comparison results, namely the comparison result between the actual slip ratio of the outer front wheel and its corresponding target slip ratio, the comparison result between the actual slip ratio of the inner front wheel and its corresponding target slip ratio, the comparison result between the actual slip ratio of the inner rear wheel and its corresponding target slip ratio, and the comparison result between the actual slip ratio of the outer rear wheel and its corresponding target slip ratio.

[0127] In this embodiment, if the slip ratio of the outer front wheel is less than its corresponding target slip ratio in the third comparison result, the positive driving torque of the outer front wheel of the vehicle is increased to increase the slip ratio of the outer front wheel of the vehicle, so that the outer front wheel of the vehicle reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0128] Step S102: If the third comparison result includes the slip ratio of the outer front wheel being greater than its corresponding target slip ratio, reduce the positive drive torque of the outer front wheel.

[0129] In this embodiment, if the slip ratio of the outer front wheel is greater than its corresponding target slip ratio in the third comparison result, the positive drive torque of the outer front wheel of the vehicle is reduced, thereby reducing the slip ratio of the outer front wheel of the vehicle so that the outer front wheel of the vehicle reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0130] Step S103: If the third comparison result includes the slip ratio of the inner front wheel being less than its corresponding target slip ratio, increase the positive drive torque of the inner front wheel or decrease the braking torque of the inner front wheel.

[0131] In this embodiment, if the slip ratio of the inner front wheel is less than its corresponding target slip ratio in the third comparison result, the positive driving torque of the inner front wheel is increased or the braking torque of the inner front wheel is decreased, thereby increasing the slip ratio of the inner front wheel of the vehicle so that the inner front wheel of the vehicle reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0132] Step S104: If the third comparison result includes the slip ratio of the inner front wheel being greater than its corresponding target slip ratio, reduce the positive drive torque of the inner front wheel or increase the braking torque of the inner front wheel.

[0133] In this embodiment, if the slip ratio of the inner front wheel is greater than its corresponding target slip ratio in the third comparison result, the positive driving torque of the inner front wheel is reduced, or the braking torque of the inner front wheel is increased, so as to reduce the slip ratio of the inner front wheel of the vehicle, so that the inner front wheel of the vehicle reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0134] Step S105: If the third comparison result includes the slip ratio of the inner rear wheel being less than its corresponding target slip ratio, increase the reverse drive torque of the inner rear wheel.

[0135] In this embodiment, if the slip ratio of the inner rear wheel is less than its corresponding target slip ratio in the third comparison result, the reverse driving torque of the inner rear wheel is increased to increase the slip ratio of the inner rear wheel of the vehicle, so that the inner rear wheel of the vehicle reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0136] Step S106: If the third comparison result includes the slip ratio of the inner rear wheel being greater than its corresponding target slip ratio, reduce the reverse drive torque of the inner rear wheel.

[0137] In this embodiment, if the slip ratio of the inner rear wheel is greater than its corresponding target slip ratio in the third comparison result, the reverse drive torque of the inner rear wheel of the vehicle is reduced, thereby reducing the slip ratio of the inner rear wheel of the vehicle, so that the inner rear wheel of the vehicle reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0138] Step S107: If the third comparison result includes the slip ratio of the outer rear wheel being less than its corresponding target slip ratio, increase the reverse drive torque of the outer rear wheel or decrease the braking torque of the outer rear wheel.

[0139] In this embodiment, if the slip ratio of the outer rear wheel is less than its corresponding target slip ratio in the third comparison result, the reverse drive torque of the outer rear wheel is increased or the braking torque of the outer rear wheel is decreased to increase the slip ratio of the outer rear wheel, so that the outer rear wheel reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0140] Step S108: If the third comparison result includes the slip ratio of the outer rear wheel being greater than its corresponding target slip ratio, reduce the reverse drive torque of the outer rear wheel or increase the braking torque of the outer rear wheel.

[0141] In this embodiment, if the slip ratio of the outer rear wheel is greater than its corresponding target slip ratio in the third comparison result, the reverse drive torque of the outer rear wheel is reduced or the braking torque of the outer rear wheel is increased to reduce the slip ratio of the outer rear wheel, so that the outer rear wheel reaches the predetermined slip ratio, that is, reaches its corresponding target slip ratio.

[0142] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. In this steering assist control method, step S8 may include steps S81 to S82:

[0143] Step S81: Obtain a pre-constructed second correspondence, which includes the correspondence between the driving terrain and the target slip ratio of the wheels. The target slip ratio of the wheels includes the target slip ratio of the left front wheel, the target slip ratio of the right front wheel, the target slip ratio of the left rear wheel, and the target slip ratio of the right rear wheel.

[0144] In this embodiment, due to the varying adhesion of the bottom surface on different terrains, the degree of slippage of each wheel of the vehicle corresponding to the same deflection torque applied to the vehicle varies depending on the terrain. Therefore, in order to ensure that the steering assist control method provided in this application performs well in minimizing the turning radius under various driving terrain scenarios, this application pre-constructs corresponding target slip ratios for each wheel for different driving terrains. That is, for each driving terrain, there is a target slip ratio corresponding to the left front wheel, the right front wheel, the left rear wheel, and the right rear wheel, so that the vehicle performs well in minimizing the turning radius when turning under various terrains. Specifically: A second correspondence is pre-constructed, which includes the correspondence between the driving terrain and the target slip ratio of the wheels. The target slip ratio of the vehicle includes the target slip ratio of the left front wheel, the target slip ratio of the right front wheel, the target slip ratio of the left rear wheel, and the target slip ratio of the right rear wheel. That is, for a given driving terrain, there is a target slip ratio corresponding to the left front wheel, the right front wheel, the left rear wheel, and the right rear wheel. First, this pre-constructed second correspondence is obtained.

[0145] Step S82: Determine the target slip ratio of each wheel corresponding to the driving terrain based on the driving terrain of the vehicle and the second correspondence.

[0146] In this embodiment, after obtaining the pre-constructed second correspondence, the driving terrain of the current vehicle is determined. Then, based on the driving terrain and the second correspondence, the target slip ratios corresponding to the left front wheel, right front wheel, left rear wheel, and right rear wheel of the vehicle corresponding to the driving terrain are determined. The driving terrain includes, but is not limited to, snow, mud, sand, and concrete. The method of determining the driving terrain can be by user selection via the control interface or by analyzing information collected by various vehicle sensors; no specific limitation is made here.

[0147] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. This steering assist control method further includes steps S11 to S13:

[0148] Step S11: During the process of adjusting the torque applied to the wheels of the vehicle, monitor the front axle deflection torque and the rear axle deflection torque of the vehicle.

[0149] In this embodiment, the target deflection torque for the front axle and the target deflection torque for the rear axle are determined based on the driving terrain. Controlling the vehicle to travel with these target deflection torques on the front and rear axles under these terrains allows for a significant reduction in the turning radius. To prevent instability and other safety accidents when adjusting the torque based on the vehicle's yaw rate and / or slip rate, this application monitors the front and rear axle deflection torques in real time when adjusting the torque based on the yaw rate and / or slip rate, and makes new torque control adjustments based on the monitored front and rear axle deflection torques.

[0150] Step S12: Compare the monitored front axle deflection torque with the upper limit of the torque range of the determined front axle target deflection torque, and compare the monitored rear axle deflection torque with the upper limit of the torque range of the determined rear axle target deflection torque to obtain a fourth comparison result.

[0151] In this embodiment, the actual front axle deflection torque of the vehicle obtained by monitoring is compared with the upper limit of the torque range of the determined target front axle deflection torque, and the actual rear axle deflection torque of the vehicle obtained by monitoring is compared with the upper limit of the torque range of the determined target rear axle deflection torque, to obtain a total fourth comparison result.

[0152] Step S13: Based on the fourth comparison result, determine whether to end the adjustment of the applied torque.

[0153] In this embodiment, based on the specific performance of the fourth comparison result, it is determined whether to end the adjustment of the applied torque to prevent vehicle instability and other safety accidents.

[0154] In conjunction with the above embodiments, in one implementation, this application also provides a method for steering assist control. In this steering assist control method, step S13 may include: ending the adjustment of the applied torque when the fourth comparison result indicates that the deviation between the front axle deflection torque and the upper limit of the torque range of the front axle target deflection torque is within a first preset range, and / or the deviation between the rear axle deflection torque and the upper limit of the torque range of the rear axle target deflection torque is within a second preset range.

[0155] In this embodiment, the adjustment of the applied torque ends when the fourth result represents the actual front axle deflection torque of the vehicle being less than the upper limit of the determined target front axle deflection torque range, and the deviation between the two is within a first preset range, and / or the actual rear axle deflection torque of the vehicle being less than the upper limit of the determined target rear axle deflection torque range, and the deviation between the two is within a second preset range. The first and second preset ranges can be the same or different, and both can be set according to the actual application scenario; no specific limitation is made here.

[0156] For example, the upper limit of the torque range to the target deflection torque of the front axle is determined to be a1, the actual front axle deflection torque of the vehicle is a, and the first preset range is [0,5]. The actual front axle deflection torque a of the vehicle is compared with the upper limit of the torque range a1 of the determined target deflection torque of the front axle. When a is less than a1, and the deviation obtained by subtracting a1 from a is between [0,5], it is determined that the current torque adjustment of the vehicle has reached a suitable state. At this time, the current torque state is maintained and no further torque increase or decrease (including drive torque and braking torque) operations are performed. The upper limit of the torque range for the target rear axle deflection torque is determined to be b1, the actual rear axle deflection torque of the vehicle is b, and the second preset range is [0,6]. The actual rear axle deflection torque b of the vehicle is compared with the upper limit of the torque range b1 for the target rear axle deflection torque. When b is less than b1, and the deviation obtained by subtracting b1 from b is between [0,6], it is determined that the current torque adjustment of the vehicle has reached a suitable state. At this time, the current torque state is maintained and no further torque increase or decrease (including drive torque and braking torque) operations are performed.

[0157] Based on the same inventive concept, one embodiment of this application provides a steering assistance control system, such as... Figure 4 As shown, the system 400 includes:

[0158] Signal acquisition module 401 is used to acquire target signals;

[0159] The function control module 402 is used to determine whether to activate the steering assist function based on the acquired target signal;

[0160] The torque determination module 403 is used to determine the target deflection torque of the front axle and the target deflection torque of the rear axle based on the driving terrain when the steering assist function is activated.

[0161] The first control module 404 is used to control the front axle drive motor to apply a corresponding positive drive torque to the front wheels of the vehicle and a corresponding braking torque to the steering inner front wheels of the vehicle according to the target deflection torque of the front axle, so as to control the front axle of the vehicle to obtain the target deflection torque of the front axle.

[0162] The second control module 405 is used to control the rear axle drive motor to apply a corresponding reverse drive torque to the rear wheels of the vehicle and a corresponding braking torque to the outer rear wheel of the vehicle, based on the target deflection torque of the rear axle, so as to control the rear axle of the vehicle to obtain the target deflection torque of the rear axle.

[0163] Optionally, the system 400 further includes:

[0164] The yaw rate determination module is used to determine the yaw rate of the vehicle based on the acquired yaw rate signal of the vehicle.

[0165] The first comparison module is used to compare the yaw rate with a first target threshold and a second target threshold respectively to obtain a first comparison result;

[0166] The first correction module is used to adjust the torque applied to the wheels of the vehicle based on the first comparison result, so as to correct the yaw rate of the vehicle.

[0167] Optionally, the first correction module includes:

[0168] The first torque adjustment module is used to increase the positive drive torque of the outer front wheel and the braking torque of the inner front wheel when the first comparison result indicates that the yaw rate is less than or equal to the first target threshold, and / or increase the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel.

[0169] The second torque adjustment module is used to reduce the positive drive torque of the outer front wheel and the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel when the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold.

[0170] Optionally, the system 400 further includes:

[0171] The instability yaw rate determination module is used to determine the instability yaw rate based on the vehicle speed and steering wheel angle when the first comparison result indicates that the yaw rate is greater than or equal to a second target threshold.

[0172] The second comparison module is used to compare the yaw rate with the instability yaw rate to obtain a second comparison result;

[0173] The third torque adjustment module is used to control the application of positive driving torque and the termination of braking torque to all wheels of the vehicle when the second comparison result indicates that the yaw rate is greater than or equal to the instability yaw rate.

[0174] The fourth torque adjustment module is used to control the execution of the second torque adjustment module when the second comparison result indicates that the yaw rate is less than the instability yaw rate.

[0175] Optionally, the system 400 further includes:

[0176] The target slip ratio determination module is used to determine the target slip ratio corresponding to each wheel of the vehicle based on the driving terrain.

[0177] The third comparison module is used to compare the slip ratio of each wheel of the vehicle with its corresponding target slip ratio to obtain a third comparison result.

[0178] The second correction module is used to adjust the torque applied to the wheels of the vehicle based on the third comparison result, so as to correct the slip ratio of each wheel of the vehicle.

[0179] Optionally, the second correction module includes:

[0180] The first adjustment module is used to increase the positive drive torque of the outer front wheel when the third comparison result includes the slip ratio of the outer front wheel being less than its corresponding target slip ratio.

[0181] The second adjustment module is used to reduce the positive drive torque of the outer front wheel when the third comparison result includes the slip ratio of the outer front wheel being greater than its corresponding target slip ratio.

[0182] The third adjustment module is used to increase the positive drive torque of the inner front wheel or decrease the braking torque of the inner front wheel when the third comparison result includes the slip ratio of the inner front wheel being less than its corresponding target slip ratio.

[0183] The fourth adjustment module is used to reduce the positive drive torque of the inner front wheel or increase the braking torque of the inner front wheel when the third comparison result includes the slip ratio of the inner front wheel being greater than its corresponding target slip ratio.

[0184] The fifth adjustment module is used to increase the reverse drive torque of the inner rear wheel when the third comparison result includes the slip ratio of the inner rear wheel being less than its corresponding target slip ratio.

[0185] The sixth adjustment module is used to reduce the reverse drive torque of the inner rear wheel when the third comparison result includes the slip ratio of the inner rear wheel being greater than its corresponding target slip ratio.

[0186] The seventh adjustment module is used to increase the reverse drive torque of the outer rear wheel or decrease the braking torque of the outer rear wheel when the third comparison result includes the slip ratio of the outer rear wheel being less than its corresponding target slip ratio.

[0187] The eighth adjustment module is used to reduce the reverse drive torque of the outer rear wheel or increase the braking torque of the outer rear wheel when the third comparison result includes the slip ratio of the outer rear wheel being greater than its corresponding target slip ratio.

[0188] Optionally, the torque determination module 403 includes:

[0189] The first acquisition module is used to acquire a pre-constructed first correspondence relationship, which includes the correspondence between driving terrain and target deflection torque, and the target deflection torque includes front axle target deflection torque and rear axle target deflection torque;

[0190] The torque determination submodule is used to determine the target deflection torque of the front axle and the target deflection torque of the rear axle corresponding to the driving terrain based on the driving terrain of the vehicle and the first correspondence.

[0191] Optionally, the target slip ratio determination module includes:

[0192] The second acquisition module is used to acquire a pre-constructed second correspondence relationship, which includes the correspondence between the driving terrain and the target slip ratio of the wheels. The target slip ratio of the wheels includes the target slip ratio of the left front wheel, the target slip ratio of the right front wheel, the target slip ratio of the left rear wheel, and the target slip ratio of the right rear wheel.

[0193] The target slip ratio determination submodule is used to determine the target slip ratio of each wheel corresponding to the driving terrain based on the driving terrain of the vehicle and the second correspondence.

[0194] Optionally, the system 400 further includes:

[0195] The data monitoring module is used to monitor the front axle deflection torque and rear axle deflection torque of the vehicle during the process of adjusting the torque applied to the wheels of the vehicle.

[0196] The fourth comparison module is used to compare the monitored front axle deflection torque with the upper limit of the torque range of the determined front axle target deflection torque, and to compare the monitored rear axle deflection torque with the upper limit of the torque range of the determined rear axle target deflection torque, to obtain a fourth comparison result.

[0197] The torque adjustment determination module is used to determine whether to end the adjustment of the applied torque based on the fourth comparison result.

[0198] Optionally, the torque adjustment determining module includes:

[0199] The torque adjustment determination submodule is used to terminate the adjustment of the applied torque when the fourth comparison result indicates that the deviation between the front axle deflection torque and the upper limit of the torque range of the front axle target deflection torque is within a first preset range, and / or the deviation between the rear axle deflection torque and the upper limit of the torque range of the rear axle target deflection torque is within a second preset range.

[0200] Optionally, the target signals in the signal acquisition module include: steering assist function switch signal, steering wheel angle signal, and accelerator pedal signal.

[0201] Based on the same inventive concept, a third aspect of this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements a steering assistance control method as described in the first aspect of this application.

[0202] Based on the same inventive concept, a fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements a steering assistance control method as described in the first aspect of this application.

[0203] As the method embodiments are basically similar to the system embodiments, the description is relatively simple, and relevant parts can be found in the description of the system embodiments.

[0204] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily necessary for the embodiments of this application.

[0205] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0206] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, embodiments of this application can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of this application can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0207] This application describes embodiments with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0208] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0209] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0210] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0211] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0212] The above provides a detailed description of the steering assist control method, system, device, and medium provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for steering assist control, characterized in that, Applied to a dual-motor driven vehicle, the vehicle including a braking system capable of independently controlling each wheel, the method includes: Based on the acquired target signal, determine whether to activate the steering assist function; When the steering assist function is activated, the target yaw torque for the front axle and the target yaw torque for the rear axle are determined according to the driving terrain. Based on the target deflection torque of the front axle, the front axle drive motor is controlled to apply a corresponding positive drive torque to the front wheels of the vehicle and a corresponding braking torque to the steering inner front wheels of the vehicle, so as to control the front axle of the vehicle to obtain the target deflection torque of the front axle. Based on the target deflection torque of the rear axle, the rear axle drive motor is controlled to apply a corresponding reverse drive torque to the rear wheels of the vehicle and a corresponding braking torque to the outer rear wheel of the vehicle, so as to control the rear axle of the vehicle to obtain the target deflection torque of the rear axle. The method further includes: The yaw rate of the vehicle is determined based on the acquired yaw rate signal of the vehicle. The yaw rate is compared with the first target threshold and the second target threshold respectively to obtain the first comparison result; Based on the first comparison result, the torque applied to the wheels of the vehicle is adjusted to correct the yaw rate of the vehicle. Based on the first comparison result, adjusting the torque applied to the wheels of the vehicle to correct the yaw rate of the vehicle includes: When the first comparison result indicates that the yaw rate is less than or equal to the first target threshold, increase the positive drive torque of the outer front wheel and increase the braking torque of the inner front wheel, and / or increase the reverse drive torque of the inner rear wheel and increase the braking torque of the outer rear wheel. If the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, reduce the positive drive torque of the outer front wheel and reduce the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and reduce the braking torque of the outer rear wheel. Before reducing the positive drive torque of the outer front wheel and the braking torque of the inner front wheel, and / or reducing the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel, when the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, the method further includes: If the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold, the instability yaw rate is determined based on the vehicle speed and steering wheel angle. The yaw rate is compared with the instability yaw rate to obtain a second comparison result; If the second comparison result indicates that the yaw rate is greater than or equal to the instability yaw rate, control the application of positive driving torque and the termination of braking torque to all wheels of the vehicle. If the second comparison result indicates that the yaw rate is less than the instability yaw rate, the following steps are performed: reduce the positive drive torque of the outer front wheel and reduce the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and reduce the braking torque of the outer rear wheel.

2. The steering assist control method according to claim 1, characterized in that, The method further includes: Based on the driving terrain, determine the target slip ratio corresponding to each wheel of the vehicle; The slip ratio of each wheel of the vehicle is compared with its corresponding target slip ratio to obtain a third comparison result; Based on the third comparison result, the torque applied to the wheels of the vehicle is adjusted to correct the slip ratio of each wheel of the vehicle.

3. The steering assist control method according to claim 2, characterized in that, Based on the third comparison result, the torque applied to the wheels of the vehicle is adjusted to correct the slip ratio of each wheel of the vehicle, including: If the slip ratio of the outer front wheel is less than its corresponding target slip ratio, the positive drive torque of the outer front wheel is increased. If the slip ratio of the outer front wheel is greater than its corresponding target slip ratio, the positive drive torque of the outer front wheel is reduced. If the slip ratio of the inner front wheel is less than its corresponding target slip ratio, the positive drive torque of the inner front wheel is increased or the braking torque of the inner front wheel is decreased in the third comparison result. If the third comparison result includes a slip ratio of the inner front wheel that is greater than its corresponding target slip ratio, the positive drive torque of the inner front wheel is reduced or the braking torque of the inner front wheel is increased. If the slip ratio of the inner rear wheel is less than its corresponding target slip ratio, the reverse drive torque of the inner rear wheel is increased. If the slip ratio of the inner rear wheel is greater than its corresponding target slip ratio, the reverse drive torque of the inner rear wheel is reduced. If the slip ratio of the outer rear wheel is less than its corresponding target slip ratio, the reverse drive torque of the outer rear wheel is increased or the braking torque of the outer rear wheel is decreased in the third comparison result. If the third comparison result includes a slip ratio of the outer rear wheel that is greater than its corresponding target slip ratio, the reverse drive torque of the outer rear wheel is reduced or the braking torque of the outer rear wheel is increased.

4. The steering assist control method according to claim 1, characterized in that, Based on the driving terrain, determine the target yaw torque for the front axle and the target yaw torque for the rear axle, including: Obtain a pre-constructed first correspondence, which includes the correspondence between driving terrain and target deflection torque, wherein the target deflection torque includes front axle target deflection torque and rear axle target deflection torque; Based on the vehicle's driving terrain and the first correspondence, the target deflection torque of the front axle and the target deflection torque of the rear axle corresponding to the driving terrain are determined.

5. The steering assist control method according to claim 2, characterized in that, Based on the driving terrain, determine the target slip ratio corresponding to each wheel of the vehicle, including: Obtain a pre-constructed second correspondence, which includes the correspondence between the driving terrain and the target slip ratio of the wheels, wherein the target slip ratio of the wheels includes the target slip ratio of the left front wheel, the target slip ratio of the right front wheel, the target slip ratio of the left rear wheel, and the target slip ratio of the right rear wheel; Based on the driving terrain of the vehicle and the second correspondence, the target slip ratio of each wheel corresponding to the driving terrain is determined.

6. The steering assist control method according to claim 2, characterized in that, The method further includes: During the adjustment of the torque applied to the wheels of the vehicle, the front axle deflection torque and the rear axle deflection torque of the vehicle are monitored. The front axle deflection torque obtained by monitoring is compared with the upper limit of the torque range of the determined front axle target deflection torque, and the rear axle deflection torque obtained by monitoring is compared with the upper limit of the torque range of the determined rear axle target deflection torque to obtain a fourth comparison result. Based on the fourth comparison result, determine whether to end the adjustment of the applied torque.

7. The steering assist control method according to claim 6, characterized in that, Based on the fourth comparison result, determine whether to end the adjustment of the applied torque, including: If the fourth comparison result indicates that the deviation between the front axle deflection torque and the upper limit of the torque range of the target front axle deflection torque is within a first preset range, and / or the deviation between the rear axle deflection torque and the upper limit of the torque range of the target rear axle deflection torque is within a second preset range, the adjustment of the applied torque ends.

8. The steering assist control method according to claim 1, characterized in that, The target signals include: steering assist function switch signal, steering wheel angle signal, and accelerator pedal signal.

9. A steering assist control system, characterized in that, The system includes: The signal acquisition module is used to acquire the target signal; The function control module is used to determine whether to activate the steering assist function based on the acquired target signal; The torque determination module is used to determine the target deflection torque of the front axle and the target deflection torque of the rear axle based on the driving terrain when the steering assist function is activated. The first control module is used to control the front axle drive motor to apply a corresponding positive drive torque to the front wheels of the vehicle and a corresponding braking torque to the steering inner front wheels of the vehicle according to the target deflection torque of the front axle, so as to control the front axle of the vehicle to obtain the target deflection torque of the front axle. The second control module is used to control the rear axle drive motor to apply a corresponding reverse drive torque to the rear wheels of the vehicle and a corresponding braking torque to the outer rear wheel of the vehicle, based on the target deflection torque of the rear axle, so as to control the rear axle of the vehicle to obtain the target deflection torque of the rear axle. The system also includes: The yaw rate determination module is used to determine the yaw rate of the vehicle based on the acquired yaw rate signal of the vehicle. The first comparison module is used to compare the yaw rate with a first target threshold and a second target threshold respectively to obtain a first comparison result; The first correction module is used to adjust the torque applied to the wheels of the vehicle based on the first comparison result in order to correct the yaw rate of the vehicle. The first correction module includes: The first torque adjustment module is used to increase the positive drive torque of the outer front wheel and the braking torque of the inner front wheel when the first comparison result indicates that the yaw rate is less than or equal to the first target threshold, and / or increase the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel. The second torque adjustment module is used to reduce the positive drive torque of the outer front wheel and the braking torque of the inner front wheel, and / or reduce the reverse drive torque of the inner rear wheel and the braking torque of the outer rear wheel when the first comparison result indicates that the yaw rate is greater than or equal to the second target threshold. The instability yaw rate determination module is used to determine the instability yaw rate based on the vehicle speed and steering wheel angle when the first comparison result indicates that the yaw rate is greater than or equal to a second target threshold. The second comparison module is used to compare the yaw rate with the instability yaw rate to obtain a second comparison result; The third torque adjustment module is used to control the application of positive driving torque and the termination of braking torque to all wheels of the vehicle when the second comparison result indicates that the yaw rate is greater than or equal to the instability yaw rate. The fourth torque adjustment module is used to control the execution of the second torque adjustment module when the second comparison result indicates that the yaw rate is less than the instability yaw rate.

10. An electronic device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements a steering assist control method as described in claims 1 to 8.

11. A computer-readable storage medium storing a computer program thereon, characterized in that, When the computer program is executed by the processor, it implements a steering assist control method as described in any one of claims 1 to 8.

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