Vehicle steering control method, controller, vehicle, medium and program product

Abstract

The invention relates to the technical field of vehicle steering control, and provides a vehicle steering control method, a controller, a vehicle, a medium and a program product. The vehicle steering control method comprises the steps that it is determined that a steering system of a vehicle breaks down; through the driving system of the vehicle and / or the braking system of the vehicle, the left wheel and the right wheel of the vehicle are controlled to generate the wheel speed difference, so that the vehicle steers, safety accidents are avoided, and the driving safety is improved.

Description

Technical Field

[0001] This disclosure relates to the field of vehicle steering control technology, specifically to a vehicle steering control method, controller, vehicle, medium, and program product. Background Technology

[0002] Steering control is a core part of vehicle dynamics, directly affecting vehicle stability, safety, and driving performance.

[0003] In related technologies, when a vehicle's steering system malfunctions, the driver cannot control the steering by manipulating the steering wheel, which can easily lead to safety accidents. Summary of the Invention

[0004] The purpose of this disclosure is to provide a vehicle steering control method, controller, vehicle, medium, and program product to solve problems in the related art.

[0005] To achieve the above objectives, a first aspect of this disclosure provides a vehicle steering control method, comprising: It was determined that the vehicle's steering system had malfunctioned; By controlling the wheel speed difference between the left and right wheels of the vehicle through the vehicle's drive system and / or braking system, the vehicle can be steered.

[0006] Optionally, controlling the wheel speed difference between the left and right wheels of the vehicle through the vehicle's drive system and / or braking system includes: Based on the driver’s desired yaw rate and the vehicle’s actual yaw rate, a first target wheel speed for the left wheel and a second target wheel speed for the right wheel of the vehicle are determined, wherein the first target wheel speed and the second target wheel speed are different. Based on the first target wheel speed and the second target wheel speed, determine the first control torque increment of the left wheel and the second control torque increment of the right wheel; Based on the first control torque increment and the second control torque increment, different drive torques are output to the left and right wheels of the vehicle through the drive system, and / or different braking torques are output to the left and right wheels of the vehicle through the braking system, so that the wheel speed of the left wheel of the vehicle reaches the first target wheel speed and the wheel speed of the right wheel of the vehicle reaches the second target wheel speed.

[0007] Optionally, the vehicle steering control method further includes: The difference between the actual wheel speed and the corresponding target wheel speed is used as the error value, and the control torque increment corresponding to the wheel is used as the control value to perform feedback control on the control torque increment of the wheel.

[0008] Optionally, the step of outputting different driving torques to the left and right wheels of the vehicle through the drive system, and / or outputting different braking torques to the left and right wheels of the vehicle through the braking system, includes: The inner and outer wheels of the vehicle are determined from the left and right wheels based on the steering wheel angle. The vehicle's drive system is a single-motor drive system, which outputs drive torque to the outer wheels via a single drive motor and brake torque to the inner wheels via a braking system; or... The drive system is a multi-motor drive system, in which one of the multiple drive motors outputs positive torque to the outer wheel and another of the multiple drive motors outputs negative torque to the inner wheel.

[0009] Optionally, determining the first target wheel speed of the left wheel and the second target wheel speed of the right wheel based on the driver's desired yaw rate and the vehicle's actual yaw rate includes: Based on the driver's desired yaw rate and the vehicle's actual yaw rate, and constrained by the wheel slip ratio being less than a slip ratio threshold and / or the wheel spin ratio being less than a spin ratio threshold, the first target wheel speed of the vehicle's left wheel and the second target wheel speed of the right wheel are determined.

[0010] Optionally, determining the first target wheel speed of the left wheel and the second target wheel speed of the right wheel based on the driver's desired yaw rate and the vehicle's actual yaw rate includes: The inner and outer wheels of the vehicle are determined from the left and right wheels based on the steering wheel angle. The wheel speed increment is determined based on the difference between the driver's desired yaw rate and the vehicle's actual yaw rate. The difference between the actual wheel speed of the inner wheel and the wheel speed increment is taken as the target wheel speed of the inner wheel; The sum of the actual wheel speed of the outer wheel and the wheel speed increment is taken as the target wheel speed of the outer wheel.

[0011] Optionally, the vehicle steering control method further includes: The difference between the driver's desired yaw rate and the actual yaw rate is used as the error quantity, and the wheel speed increment of the left and right wheels of the vehicle is used as the control quantity to perform feedback control on the wheel speed increment of the left and right wheels of the vehicle.

[0012] Optionally, both the left and right wheels of the vehicle are the rear wheels, and the vehicle steering control method further includes: Obtain the driver's requested torque, and the sum of the first control torque increment and the second control torque increment; The drive torque for controlling the front wheels of the vehicle is determined based on the difference between the requested torque and the sum.

[0013] Optionally, determining that the vehicle's steering system has malfunctioned includes: The vehicle's steering system is determined to be malfunctioning based on at least one of the ratio of the vehicle's steering wheel angular velocity to the motor's rotational angular velocity, and the difference between the driver's desired yaw rate and the vehicle's actual yaw rate.

[0014] According to a second aspect of the present disclosure, a controller is provided, comprising: A memory on which computer programs are stored; A processor is configured to execute the computer program in the memory to implement the steps of any of the vehicle steering control methods provided in the first aspect of this disclosure.

[0015] According to a third aspect of the present disclosure, a vehicle is provided, the vehicle including the controller provided in the second aspect of the present disclosure.

[0016] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the vehicle steering control methods provided in the first aspect of the present disclosure.

[0017] According to a fifth aspect of the present disclosure, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps of any of the vehicle steering control methods provided in the first aspect of the present disclosure.

[0018] By employing the above technical solution, when a malfunction is determined in the vehicle's steering system, the vehicle's drive system and / or braking system can be used to control the wheel speed difference between the left and right wheels, thereby steering the vehicle, preventing accidents, and improving driving safety.

[0019] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a block diagram illustrating a vehicle according to an exemplary embodiment.

[0021] Figure 2 This is a flowchart illustrating a vehicle steering control method according to an exemplary embodiment.

[0022] Figure 3 This is a flowchart illustrating a sub-step of step S2 according to an exemplary embodiment.

[0023] Figure 4 This is a flowchart illustrating a sub-step of step S21 according to an exemplary embodiment.

[0024] Figure 5 This is a block diagram illustrating a vehicle steering control device according to an exemplary embodiment. Detailed Implementation

[0025] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0026] In the following description, the words "first" and "second" are used only to distinguish the purpose of the description and should not be interpreted as indicating or implying relative importance or order.

[0027] Before introducing the specific implementation methods of this disclosure, the application scenarios of this disclosure will first be explained.

[0028] Steering control is a core part of vehicle dynamics, directly affecting vehicle stability, safety, and driving performance.

[0029] In related technologies, when a vehicle's steering system malfunctions, such as when transmission components like the steering drive shaft, spline, universal joint, ball joint, or lever arm break, the steering wheel loses its mechanical connection to the wheels, and the driver cannot control the steering by manipulating the steering wheel, which can easily lead to a safety accident.

[0030] To address the aforementioned technical issues, in the event that a malfunction has been identified in the vehicle's steering system, the vehicle's drive system and / or braking system are used to control the wheel speed difference between the left and right wheels, thereby steering the vehicle, preventing accidents, and improving driving safety.

[0031] Figure 1 This is a block diagram illustrating a vehicle according to an exemplary embodiment. Figure 1 As shown, the controller 10 can be connected to the vehicle's drive system 20 and braking system 30. Figure 2This is a flowchart illustrating a vehicle steering control method according to an exemplary embodiment. The vehicle steering control method can be applied to a controller 10 on a vehicle. It should be understood that the controller 10 can be a separately established controller or a controller reused from an existing module on the vehicle, such as a vehicle control unit (VCU), a parking distance control system (PDC), etc. This embodiment does not limit the scope of the method.

[0032] like Figure 2 As shown, the vehicle steering control method may include steps S1 and S2.

[0033] Step S1: Determine that the vehicle's steering system has malfunctioned.

[0034] Determining that a vehicle's steering system has malfunctioned can be understood as determining the malfunction based on the vehicle's operating parameters. These parameters can include, but are not limited to, vehicle speed, steering wheel angle, motor rotational angular velocity, wheel angle, and actual yaw rate.

[0035] Step S2: By controlling the vehicle's drive system and / or braking system to generate a wheel speed difference between the left and right wheels, the vehicle is steered.

[0036] The vehicle can be steered by controlling the wheel speed difference between the left and right wheels through the vehicle's drive system and / or braking system. This can be achieved by controlling the wheel speed difference between the left and right wheels through the vehicle's drive system; by controlling the wheel speed difference between the left and right wheels through the vehicle's drive system and braking system; or by controlling the wheel speed difference between the left and right wheels through the vehicle's braking system.

[0037] In the event that the vehicle's steering system has malfunctioned, the vehicle's drive system and / or braking system are used to control the wheel speed difference between the left and right wheels, thereby enabling the vehicle to steer, creating redundant steering, avoiding accidents, and improving driving safety.

[0038] In one possible implementation, please refer to Figure 3 Step S2 may include steps S21 to S23.

[0039] Step S21: Determine the first target wheel speed of the left wheel and the second target wheel speed of the right wheel based on the driver's desired yaw rate and the vehicle's actual yaw rate.

[0040] The wheel speeds of the first and second targets are different.

[0041] The difference between the first target wheel speed and the second target wheel speed creates a wheel speed difference between the left and right wheels of the vehicle.

[0042] Please see Figure 4 Step S21 may include steps S211 to S214.

[0043] Step S211: Determine the inner wheel and outer wheel from the left and right wheels of the vehicle based on the steering wheel angle.

[0044] Determine if the steering wheel angle is greater than zero. If the steering wheel angle is greater than zero, the driver is turning left, and the left wheel is the inner wheel and the right wheel is the outer wheel. If the steering wheel angle is less than zero, the driver is turning right, and the right wheel is the inner wheel and the left wheel is the outer wheel.

[0045] Step S212: Determine the wheel speed increment based on the difference between the driver's desired yaw rate and the vehicle's actual yaw rate.

[0046] The difference between the driver's desired yaw rate and the vehicle's actual yaw rate is calculated to obtain the yaw rate error. Then, the wheel speed increment is determined based on the yaw rate error.

[0047] The yaw rate error can be input into the outer loop PI controller to calculate the wheel speed increment. The wheel speed increment calculation formula is as follows: Whl=Kp1* +Ki1*∫ dt in, Whl represents the wheel speed increment, Kp1 is the proportional control coefficient of the outer loop PI controller, and Ki1 is the integral control coefficient of the outer loop PI controller. This represents the yaw rate error.

[0048] Step S213: The difference between the actual wheel speed and the wheel speed increment of the inner wheel is taken as the target wheel speed of the inner wheel.

[0049] Step S214: The sum of the actual wheel speed and the wheel speed increment of the outer wheel is taken as the target wheel speed of the outer wheel.

[0050] When the steering wheel angle is greater than zero, the left wheel of the vehicle is the inner wheel and the right wheel is the outer wheel. The target wheel speed of the inner wheel obtained through step S213 is the first target wheel speed of the left wheel of the vehicle, and the target wheel speed of the outer wheel obtained through step S214 is the second target wheel speed of the right wheel of the vehicle.

[0051] When the steering wheel angle is less than zero, the right wheel of the vehicle is the inner wheel and the left wheel is the outer wheel. The target wheel speed of the inner wheel obtained through step S213 is the second target wheel speed of the right wheel of the vehicle, and the target wheel speed of the outer wheel obtained through step S214 is the first target wheel speed of the left wheel of the vehicle.

[0052] Step S22: Determine the first control torque increment of the left wheel and the second control torque increment of the right wheel based on the first target wheel speed and the second target wheel speed.

[0053] The difference between the first target wheel speed and the actual wheel speed of the left wheel is calculated to obtain the wheel speed error of the left wheel. Then, based on the wheel speed error of the left wheel, the first control torque increment of the left wheel is determined.

[0054] The difference between the second target wheel speed and the actual wheel speed of the right wheel is calculated to obtain the wheel speed error of the right wheel. Then, based on the wheel speed error of the right wheel, the second control torque increment of the right wheel is determined.

[0055] The Kalman filter algorithm can be used to filter the actual wheel speed of the vehicle, and the delay of the filtered phase can be controlled to ensure timely response and stability.

[0056] Step S23: Based on the first control torque increment and the second control torque increment, output different driving torques to the left and right wheels of the vehicle through the drive system, and / or output different braking torques to the left and right wheels of the vehicle through the braking system, so that the wheel speed of the left wheel of the vehicle reaches the first target wheel speed and the wheel speed of the right wheel of the vehicle reaches the second target wheel speed.

[0057] The method of outputting different drive torques to the left and right wheels of a vehicle through the drive system, and / or, outputting different braking torques to the left and right wheels of a vehicle through the braking system, may include: The inner and outer wheels of the vehicle are determined from the left and right wheels based on the steering wheel angle. The vehicle uses a single drive motor to output drive torque to the outer wheels and a braking system to output braking torque to the inner wheels; this is a single-motor drive system. The drive system is a multi-motor drive system, in which one of the multiple drive motors outputs positive torque to the outer wheel and another of the multiple drive motors outputs negative torque to the inner wheel.

[0058] For example, the motor drive torque corresponding to the outer wheel is obtained based on the control torque increment of the outer wheel, and the motor drive torque corresponding to the outer wheel is sent to the drive system to output drive torque for driving. The hydraulic pressure value corresponding to the inner wheel is obtained based on the control torque increment of the inner wheel, and the hydraulic pressure value corresponding to the wheel is sent to the braking system to output braking torque for braking.

[0059] Specifically, obtaining the motor drive torque corresponding to the outer wheel based on the control torque increment of the outer wheel can be understood as multiplying the control torque increment of the outer wheel by a preset multiplier. For example, the preset multiplier can be 2. Similarly, obtaining the hydraulic pressure value corresponding to the inner wheel based on the control torque increment of the inner wheel can be understood as multiplying the control torque increment of the inner wheel by a preset conversion coefficient.

[0060] To prevent the requested torque from exceeding the motor's capacity, a maximum value limit can be set for the motor drive torque corresponding to the outer wheel. The motor drive torque corresponding to the outer wheel is compared with the motor's maximum output torque; if the motor drive torque corresponding to the outer wheel exceeds the motor's maximum output torque, the motor drive torque corresponding to the outer wheel is updated to the motor's maximum output torque.

[0061] It should be noted that the steering control of single-motor and three-motor vehicles is similar to that of two-motor vehicles. Single-motor vehicles can achieve steering control using a single motor and braking system, following the differential torque steering scheme described above for two-motor vehicles. Three-motor vehicles utilize axles with both front and rear motors to output positive and negative torque respectively. The control scheme is the same as for two-motor vehicles, except that one of the coaxial dual motors can replace the braking system to output negative torque. If the negative torque output capability of the motor is insufficient, the braking system can be added. In other words, this method is applicable to single-motor, dual-motor, and three-motor vehicles, thus expanding its applicability.

[0062] In one possible implementation, the vehicle steering control method may further include: The error is calculated as the difference between the actual wheel speed and the corresponding target wheel speed, and the control torque increment corresponding to the wheel is used as the control quantity to perform feedback control on the wheel's control torque increment.

[0063] The difference between the first target wheel speed and the actual wheel speed of the left wheel is calculated to obtain the wheel speed error of the left wheel. Then, based on the wheel speed error of the left wheel, the first control torque increment of the left wheel is determined.

[0064] The difference between the second target wheel speed and the actual wheel speed of the right wheel is calculated to obtain the wheel speed error of the right wheel. Then, based on the wheel speed error of the right wheel, the second control torque increment of the right wheel is determined.

[0065] The wheel speed error can be input into the inner loop PI controller to calculate the control torque increment. The formula for calculating the control torque increment is as follows: Torq=Kp2*Whl err +Ki2*∫Whl err dt in, Torq is the control torque increment, Kp2 is the proportional element adjustment coefficient of the inner loop PI controller, Ki2 is the integral element adjustment coefficient of the inner loop PI controller, and Whl is the variable. err This represents wheel speed error. The integral term can be limited to prevent integral saturation from causing a lag in the control system response.

[0066] It should be understood that the first control torque increment of the left wheel can be determined by the wheel speed error of the left wheel and the above calculation formula, and the second control torque increment of the right wheel can be determined by the wheel speed error of the right wheel and the above calculation formula.

[0067] By using PI feedback control in the inner loop, the automatic feedback control of the wheel torque increment is improved, thus increasing accuracy.

[0068] In one possible implementation, determining the first target wheel speed of the left wheel and the second target wheel speed of the right wheel based on the driver's desired yaw rate and the vehicle's actual yaw rate may include: Based on the driver's desired yaw rate and the vehicle's actual yaw rate, and constrained by the wheel slip ratio being less than a slip ratio threshold and / or the wheel rotation ratio being less than a rotation ratio threshold, the first target wheel speed of the vehicle's left wheel and the second target wheel speed of the right wheel are determined.

[0069] The slip ratio threshold and the slip ratio threshold can be set according to actual needs. The slip ratio threshold and the slip ratio threshold can be the same or different. For example, both the slip ratio threshold and the slip ratio threshold are 20%.

[0070] Wheel slip ratio = (vehicle speed - wheel speed) / vehicle speed * 100%; Wheel slip ratio = (wheel speed - vehicle speed) / wheel speed * 100%.

[0071] After obtaining the first target wheel speed of the vehicle's left wheel and the second target wheel speed of the vehicle's right wheel through steps S211 to S214, the first target wheel speed of the left wheel is used as the wheel speed to calculate the slip ratio of the left wheel. If the slip ratio of the left wheel exceeds the slip ratio threshold, the first target wheel speed of the left wheel is reduced to the value that makes the slip ratio of the left wheel reach the slip ratio threshold. The first target wheel speed of the left wheel is used as the wheel speed to calculate the slip ratio of the left wheel. If the slip ratio of the left wheel exceeds the slip ratio threshold, the first target wheel speed of the left wheel is reduced as the wheel speed to reach the slip ratio threshold. The first target wheel speed is increased to the value that makes the slip ratio of the left wheel reach the slip ratio threshold. The second target wheel speed of the right wheel is used as the wheel speed to calculate the slip ratio of the right wheel. If the slip ratio of the right wheel exceeds the slip ratio threshold, the second target wheel speed of the right wheel is reduced to the value that makes the slip ratio of the right wheel reach the slip ratio threshold. The second target wheel speed of the right wheel is used as the wheel speed to calculate the slip ratio of the right wheel. If the slip ratio of the right wheel exceeds the slip ratio threshold, the second target wheel speed of the right wheel is increased to the value that makes the slip ratio of the right wheel reach the slip ratio threshold.

[0072] In other embodiments, the constraint may be that the wheel slip ratio is within a preset slip ratio range and / or the wheel rotation ratio is within a preset rotation ratio range.

[0073] By controlling the wheel slip ratio and wheel rotation ratio, the wheel speed can be controlled in the inner loop of the cascade PI converter to prevent wheel slippage. By keeping the wheel slip ratio and wheel rotation ratio within a safe range, the stability and safety of vehicle operation can be guaranteed.

[0074] In one possible implementation, the vehicle steering control method may further include: The error is calculated using the difference between the driver's desired yaw rate and the actual yaw rate, and the control is calculated using the wheel speed increments of the left and right wheels. Feedback control is then applied to the corresponding wheel speed increments of the left and right wheels of the vehicle.

[0075] The difference between the driver's desired yaw rate and the vehicle's actual yaw rate is calculated to obtain the yaw rate error. This yaw rate error can be input into the outer-loop PI controller to calculate the wheel speed increment. The wheel speed increment calculation formula is as follows: Whl=Kp1* +Ki1*∫ dt in, Whl represents the wheel speed increment, Kp1 is the proportional control coefficient of the outer loop PI controller, and Ki1 is the integral control coefficient of the outer loop PI controller. This represents the yaw rate error.

[0076] For vehicles with two motors, only the rear wheel motor and braking system are used for differential torque control, while the front wheel motor and braking system are used to control the overall vehicle torque, so that the overall vehicle torque can accurately respond to the driver's throttle torque request.

[0077] In one possible implementation, both the left and right wheels of the vehicle are rear wheels, and the vehicle steering control method may further include: Obtain the driver's requested torque, and the sum of the first control torque increment and the second control torque increment; The drive torque used to control the front wheels of the vehicle is determined based on the difference between the requested torque and the sum of the values.

[0078] The difference is obtained by subtracting the sum of the control torque increments of the rear wheels from the driver's requested torque. This difference is then used as the drive torque output to the front motor, so that the front motor can meet the driver's throttle request torque.

[0079] It should be understood that in intelligent driving systems and autonomous driving systems, the aforementioned driver-requested torque can be automatically generated by the intelligent driving system and autonomous driving system.

[0080] In one possible implementation, determining that the vehicle's steering system has malfunctioned may include: A malfunction in the vehicle's steering system is determined based on at least one of the ratio of the vehicle's steering wheel angular velocity to the motor's rotational angular velocity, and the difference between the driver's desired yaw rate and the vehicle's actual yaw rate.

[0081] Determining a malfunction in the vehicle's steering system based on the ratio of the vehicle's steering wheel angular velocity to the motor's rotational angular velocity can be understood as follows: calculate the ratio of the steering wheel angular velocity to the motor's rotational angular velocity to obtain the angular velocity ratio; compare the angular velocity ratio with a preset ratio; if the angular velocity ratio is greater than the preset ratio, it is determined that the vehicle's steering system has malfunctioned.

[0082] The steering wheel angular velocity can be obtained by detecting the steering wheel angle using an angle sensor (e.g., a TDK TAS series magnetic angle sensor) and then differentiating the steering wheel angle. The motor rotational angular velocity can be obtained by detecting a position sensor.

[0083] To further improve the accuracy of diagnosing steering system malfunctions, the duration for which the angular velocity ratio is greater than a preset ratio can be counted to obtain a first duration. If the first duration exceeds a preset first duration threshold, it can be determined that the vehicle's steering system has malfunctioned.

[0084] The difference between the driver's desired yaw rate and the vehicle's actual yaw rate determines whether the vehicle's steering system is malfunctioning. This can be understood as calculating the absolute difference between the vehicle's actual yaw rate and the driver's desired yaw rate to obtain the absolute difference in yaw rate; if the absolute difference in yaw rate is greater than the preset absolute difference, it is determined that the vehicle's steering system is malfunctioning.

[0085] The Kalman filter algorithm can be used to filter the vehicle's actual yaw rate, and the phase delay after filtering can be controlled to ensure timely response and stability. The driver's desired yaw rate can be obtained based on the vehicle's longitudinal speed and the front wheel steering angle.

[0086] The formula for calculating the driver's desired yaw rate is:

[0087] in, The driver's desired yaw rate, The longitudinal speed of the vehicle. The front wheel steering angle is the angle at which the wheels turn. As a stability factor, This refers to the wheelbase.

[0088] To further improve the accuracy of diagnosing steering system malfunctions, a second duration can be obtained by statistically analyzing the duration during which the absolute difference in angular velocity exceeds a preset absolute difference. If the second duration exceeds a preset second duration threshold, a steering system malfunction is determined.

[0089] To further improve the accuracy of diagnosing steering system malfunctions, vehicle speed can be considered. If the vehicle speed exceeds a preset speed threshold, it is considered too high, requiring redundant steering intervention for assisted steering.

[0090] The vehicle speed is compared with a preset speed threshold; if the vehicle speed is greater than the preset speed threshold, the vehicle steering system is determined to be in a faulty state.

[0091] To further improve the accuracy of diagnosing steering system malfunctions, the duration of time when the vehicle speed exceeds a preset speed threshold can be counted to obtain a third duration. If the third duration exceeds a preset third duration threshold, it can be determined that the vehicle's steering system has malfunctioned.

[0092] It should be understood that the preset first duration threshold, the preset second duration threshold, and the preset third duration threshold can be set according to actual needs. The preset first duration threshold, the preset second duration threshold, and the preset third duration threshold can be the same or different. For example, the preset first duration threshold, the preset second duration threshold, and the preset third duration threshold are all 0.05s.

[0093] For example, if the ratio of the steering wheel angular velocity to the motor rotational angular velocity is greater than a preset ratio and the corresponding first duration is greater than a preset first duration threshold, then the next step is determined. If the absolute difference between the vehicle's actual yaw rate and the driver's desired yaw rate is greater than a preset absolute difference and the corresponding second duration is greater than a preset second duration threshold, then the next step is determined. If the vehicle speed is greater than a preset vehicle speed threshold and the corresponding third duration is greater than a preset third duration threshold, then the vehicle's steering system is determined to be faulty.

[0094] It should be noted that the vehicle steering control method described above can also be used in intelligent driving systems and autonomous driving systems. If a steering system transmission component breaks during driving, the intelligent driving system or autonomous driving system will take over the vehicle, plan a suitable parking route, and use redundant steering to safely stop the vehicle. Similarly, if a steering system transmission component breaks while the vehicle is in an autonomous driving system (such as LKA or City Pilot functions), the intelligent driving system or autonomous driving system can also plan a suitable parking route and use redundant steering to safely stop the vehicle.

[0095] To implement the above-described method embodiments, this embodiment provides a vehicle steering control device, which can be applied to a controller, such as... Figure 5 As shown, Figure 5 This is a block diagram illustrating a vehicle steering control device according to an exemplary embodiment. The vehicle steering control device 600 may include: The first processing module 601 is configured to determine that the vehicle's steering system has malfunctioned; The second processing module 602 is configured to control the left and right wheels of the vehicle to generate a wheel speed difference through the vehicle's drive system and / or braking system, thereby turning the vehicle.

[0096] Optionally, the second processing module 602 includes: The target wheel speed determination module is configured to determine a first target wheel speed of the left wheel and a second target wheel speed of the right wheel based on the driver's desired yaw rate and the vehicle's actual yaw rate. The first target wheel speed and the second target wheel speed are different. The control torque increment determination module is configured to determine a first control torque increment of the left wheel and a second control torque increment of the right wheel based on a first target wheel speed and a second target wheel speed. The torque output module is configured to output different drive torques to the left and right wheels of the vehicle through the drive system and / or to output different braking torques to the left and right wheels of the vehicle through the braking system, based on a first control torque increment and a second control torque increment, so that the wheel speed of the left wheel of the vehicle reaches a first target wheel speed and the wheel speed of the right wheel of the vehicle reaches a second target wheel speed.

[0097] Optionally, the vehicle steering control device also includes: The third processing module is configured to use the difference between the actual wheel speed and the corresponding target wheel speed as the error quantity, and the control torque increment corresponding to the wheel as the control quantity, to perform feedback control on the control torque increment of the wheel.

[0098] Optionally, the torque output module is specifically configured as follows: The inner and outer wheels of the vehicle are determined from the left and right wheels based on the steering wheel angle. The vehicle uses a single drive motor to output drive torque to the outer wheels and a braking system to output braking torque to the inner wheels; this is a single-motor drive system. The drive system is a multi-motor drive system, in which one of the multiple drive motors outputs positive torque to the outer wheel and another of the multiple drive motors outputs negative torque to the inner wheel.

[0099] Optionally, the target wheel speed determination module is specifically configured as follows: Based on the driver's desired yaw rate and the vehicle's actual yaw rate, and constrained by the wheel slip ratio being less than a slip ratio threshold and / or the wheel rotation ratio being less than a rotation ratio threshold, the first target wheel speed of the vehicle's left wheel and the second target wheel speed of the right wheel are determined.

[0100] Optionally, the target wheel speed determination module is specifically configured as follows: The inner and outer wheels of the vehicle are determined from the left and right wheels based on the steering wheel angle. The wheel speed increment is determined based on the difference between the driver's desired yaw rate and the vehicle's actual yaw rate. The difference between the actual wheel speed and the wheel speed increment of the inner wheel is taken as the target wheel speed of the inner wheel. The sum of the actual wheel speed and the wheel speed increment of the outer wheel is taken as the target wheel speed of the outer wheel.

[0101] Optionally, the vehicle steering control device also includes: The fourth processing module is configured to use the difference between the driver's desired yaw rate and the actual yaw rate as the error quantity, and the wheel speed increment of the left and right wheels of the vehicle as the control quantity, to perform feedback control on the wheel speed increment of the left and right wheels of the vehicle.

[0102] Optionally, both left and right wheels of the vehicle are rear wheels, and the vehicle steering control device also includes: The fifth processing module is configured to acquire the driver's requested torque, as well as the sum of the first control torque increment and the second control torque increment; The sixth processing module is configured to determine the drive torque for controlling the front wheels of the vehicle based on the difference between the requested torque and the sum.

[0103] Optionally, the first processing module 601 is specifically configured as follows: A malfunction in the vehicle's steering system is determined based on at least one of the ratio of the vehicle's steering wheel angular velocity to the motor's rotational angular velocity, and the difference between the driver's desired yaw rate and the vehicle's actual yaw rate.

[0104] Regarding the vehicle steering control device in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the vehicle steering control method, and will not be elaborated upon here.

[0105] This disclosure also provides a controller that is connected to both the vehicle's braking system and drive system. The controller may include: A memory on which computer programs are stored; A processor is used to execute a computer program in memory to implement the steps of the vehicle steering control method described above.

[0106] This disclosure also provides a vehicle that includes the controller described above.

[0107] This disclosure also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the vehicle steering control method described above.

[0108] This disclosure also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the vehicle steering control method described above.

[0109] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0110] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0111] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A vehicle steering control method, characterized in that, include: It was determined that the vehicle's steering system had malfunctioned; By controlling the wheel speed difference between the left and right wheels of the vehicle through the vehicle's drive system and / or braking system, the vehicle can be steered.

2. The vehicle steering control method according to claim 1, characterized in that, Controlling the left and right wheels of the vehicle to generate a wheel speed difference through the vehicle's drive system and / or braking system includes: Based on the driver’s desired yaw rate and the vehicle’s actual yaw rate, a first target wheel speed for the left wheel and a second target wheel speed for the right wheel of the vehicle are determined, wherein the first target wheel speed and the second target wheel speed are different. Based on the first target wheel speed and the second target wheel speed, determine the first control torque increment of the left wheel and the second control torque increment of the right wheel; Based on the first control torque increment and the second control torque increment, different drive torques are output to the left and right wheels of the vehicle through the drive system, and / or different braking torques are output to the left and right wheels of the vehicle through the braking system, so that the wheel speed of the left wheel of the vehicle reaches the first target wheel speed and the wheel speed of the right wheel of the vehicle reaches the second target wheel speed.

3. The vehicle steering control method according to claim 2, characterized in that, The vehicle steering control method also includes: The difference between the actual wheel speed and the corresponding target wheel speed is used as the error value, and the control torque increment corresponding to the wheel is used as the control value to perform feedback control on the control torque increment of the wheel.

4. The vehicle steering control method according to claim 2, characterized in that, The provision of different driving torques to the left and right wheels of the vehicle via the drive system, and / or the provision of different braking torques to the left and right wheels of the vehicle via the braking system, includes: The inner and outer wheels of the vehicle are determined from the left and right wheels based on the steering wheel angle. The vehicle's drive system is a single-motor drive system, which outputs drive torque to the outer wheels via a single drive motor and brake torque to the inner wheels via a braking system; or... The drive system is a multi-motor drive system, in which one of the multiple drive motors outputs positive torque to the outer wheel and another of the multiple drive motors outputs negative torque to the inner wheel.

5. The vehicle steering control method according to claim 2, characterized in that, The step of determining the first target wheel speed of the left wheel and the second target wheel speed of the right wheel based on the driver's desired yaw rate and the vehicle's actual yaw rate includes: Based on the driver's desired yaw rate and the vehicle's actual yaw rate, and constrained by the wheel slip ratio being less than a slip ratio threshold and / or the wheel spin ratio being less than a spin ratio threshold, the first target wheel speed of the vehicle's left wheel and the second target wheel speed of the right wheel are determined.

6. The vehicle steering control method according to claim 2, characterized in that, The step of determining the first target wheel speed of the left wheel and the second target wheel speed of the right wheel based on the driver's desired yaw rate and the vehicle's actual yaw rate includes: The inner and outer wheels of the vehicle are determined from the left and right wheels based on the steering wheel angle. The wheel speed increment is determined based on the difference between the driver's desired yaw rate and the vehicle's actual yaw rate. The difference between the actual wheel speed of the inner wheel and the wheel speed increment is taken as the target wheel speed of the inner wheel; The sum of the actual wheel speed of the outer wheel and the wheel speed increment is taken as the target wheel speed of the outer wheel.

7. The vehicle steering control method according to claim 6, characterized in that, The vehicle steering control method also includes: The difference between the driver's desired yaw rate and the actual yaw rate is used as the error quantity, and the wheel speed increment of the left and right wheels of the vehicle is used as the control quantity to perform feedback control on the wheel speed increment of the left and right wheels of the vehicle.

8. The vehicle steering control method according to claim 6, characterized in that, The vehicle has both left and right rear wheels, and the vehicle steering control method further includes: Obtain the driver's requested torque, and the sum of the first control torque increment and the second control torque increment; The drive torque for controlling the front wheels of the vehicle is determined based on the difference between the requested torque and the sum.

9. The vehicle steering control method according to any one of claims 1-8, characterized in that, The determination that the vehicle's steering system has malfunctioned includes: The vehicle's steering system is determined to be malfunctioning based on at least one of the ratio of the vehicle's steering wheel angular velocity to the motor's rotational angular velocity, and the difference between the driver's desired yaw rate and the vehicle's actual yaw rate.

10. A controller, characterized in that, include: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the vehicle steering control method according to any one of claims 1-9.

11. A vehicle, characterized in that, The vehicle includes the controller as described in claim 10.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the steps of the vehicle steering control method according to any one of claims 1-9.

13. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the steps of the vehicle steering control method according to any one of claims 1-9.

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