Torque control method and system

Abstract

According to the torque control method and system, the control method comprises the steps that the difference value between a first target angle and a current rotation angle is determined, when the first target angle is automatic steering, an electric power steering system executes the target angle according to a rotation angle request of advanced auxiliary driving, and when the current rotation angle is first torque applied to a steering wheel, the current rotation angle is the target angle executed according to the rotation angle request of advanced auxiliary driving; real included angles between wheels and the front of the vehicle; calculating a second torque of the motor according to the difference value, the vehicle speed and the first torque; wherein the second torque is the output torque of the motor, is in negative correlation with the difference value and the first torque and is in positive correlation with the vehicle speed. According to the control method, the output torque of the motor can be calculated according to the first target angle, the current rotating angle, the vehicle speed and the first torque, when the driver intervenes in taking over in advanced auxiliary driving, the resistance of the steering motor and the driver during automatic driving and the jamming feeling during intervention can be greatly reduced, the hand feeling transition of the driver is smoother, and the driver experience is improved. And meanwhile, the steering angle control precision of automatic steering can be ensured.

Description

Technical Field

[0001] This application relates to the field of autonomous driving technology, and particularly to a torque control method and system. Background Art

[0002] Currently, advanced autonomous driving is widely applied in the automotive industry. During autonomous driving, the lateral control of a vehicle is achieved by the Advanced Driving Assistance System (ADAS) controller sending a target steering wheel torque or a target steering wheel (or wheel) angle signal to the Electric Power Steering (EPS) system, and the EPS performing a steering action in one of two ways. Among them, the method of steering according to the target steering wheel torque has a lower control accuracy, but the driver's intervention feel is smoother. The method of steering according to the target steering wheel (or wheel) angle has a higher control accuracy, but the driver's intervention feel is stiffer. Therefore, it is necessary to improve the driver's intervention feel while achieving the control accuracy.

[0003] Generally, during automatic steering, when the driver intervenes in the steering, the EPS system detects the hand force of the driver operating the steering wheel through a torque sensor. When the hand force value is greater than the threshold and remains for more than a certain period of time, the steering system exits the control of the ADAS and switches to manual steering, and the EPS provides steering assistance. Since during automatic steering, when the driver's intervention hand force increases but does not reach the switching condition stage, the EPS always performs the automatic steering action, and the assist motor always has an obvious counterforce against the driver. When the threshold is reached and switched to assist steering, the hand force will quickly drop, resulting in an obvious sense of jerk and a poor driving experience. Summary of the Invention

[0004] This application provides a torque control method and system to solve the technical problem of an obvious sense of jerk when the driver intervenes in the steering during autonomous driving.

[0005] The torque control method provided in the first aspect of this application includes: determining the difference between a first target angle and the current angle, where the first target angle is the target angle executed by the EPS system according to the angle request of the ADAS during automatic steering, and the current angle is the actual angle between the wheel and the front of the vehicle when a first torque is applied to the steering wheel; calculating the second torque of the motor according to the difference, the vehicle speed, and the first torque; where the second torque is the output torque of the motor, the second torque is negatively correlated with the difference, the second torque is positively correlated with the vehicle speed, and the second torque is negatively correlated with the first torque.

[0006] In some feasible implementations, calculating the second torque of the motor based on the difference, vehicle speed, and first torque includes: calculating a target corner tolerance value based on the difference, vehicle speed, and first torque; and calculating the second torque of the motor based on the target corner tolerance value.

[0007] In some feasible implementations, calculating the second torque of the motor based on the target corner tolerance value includes: calculating a second target angle based on the first target angle and the target corner tolerance value; where the second target angle is the target angle executed by the electric power steering system according to the first torque request; determining a takeover state based on the relationship between the first target angle and the second target angle; and in response to the takeover state being a driver takeover, calculating the second torque of the motor based on the second target angle and the current corner.

[0008] In some feasible implementations, calculating the target corner tolerance value based on the difference, vehicle speed, and first torque includes: calculating the target corner tolerance value using Equation 1, where Equation 1 is:

[0009] θ error_EPS = K1·K2·θ error_ADAS ;

[0010] where θ error_EPS is the target corner tolerance value, θ error_ADAS is the difference between the first target angle and the current corner, K1 is a torque compensation coefficient, and K2 is a vehicle speed compensation coefficient; within the first preset interval, the torque compensation coefficient is positively correlated with the first torque; within the second preset interval, the vehicle speed compensation coefficient is negatively correlated with the vehicle speed.

[0011] In some feasible implementations, calculating the second torque of the motor based on the second target angle and the current corner includes:

[0012] Calculating the output torque of the motor based on the second target angle and the current corner through a PID control algorithm.

[0013] The torque control system provided in the second aspect of the present application includes: a determination module configured to determine the difference between the first target angle and the current corner, where the first target angle is the target angle executed by the electric power steering system according to the corner request of the advanced driver assistance when automatically steering, and the current corner is the true included angle between the wheel and the front of the vehicle when the driver applies a first torque to the steering wheel; a calculation module configured to calculate the second torque of the motor based on the difference, vehicle speed, and first torque; where the second torque is the output torque of the motor, the second torque is negatively correlated with the difference, the second torque is positively correlated with the vehicle speed, and the second torque is negatively correlated with the first torque.

[0014] In some feasible implementations, the calculation module is further configured to calculate a target corner tolerance value based on the difference, vehicle speed, and first torque; and calculate the second torque of the motor based on the target corner tolerance value.

[0015] In some feasible implementations, the calculation module is further configured to calculate a second target angle according to the first target angle and the target rotation angle tolerance value; wherein, the second target angle is the target angle executed by the electric power steering system according to the first torque request; determine the takeover state according to the relationship between the first target angle and the second target angle; in response to the takeover state being a driver takeover, calculate the second torque of the motor according to the second target angle and the current rotation angle.

[0016] In some feasible implementations, the calculation module is further configured to calculate the target rotation angle tolerance value by using Formula 1, and Formula 1 is:

[0017] θ error_EPS = K1·K2·θ error_ADAS ;

[0018] wherein, θ error_EPS is the target rotation angle tolerance value, θ error_ADAS is the difference between the first target angle and the current rotation angle, K1 is the torque compensation coefficient, and K2 is the vehicle speed compensation coefficient; within the first preset interval, the torque compensation coefficient is positively correlated with the first torque; within the second preset interval, the vehicle speed compensation coefficient is negatively correlated with the vehicle speed.

[0019] In some feasible implementations, the determination module is further configured to calculate the output torque of the motor according to the second target angle and the current rotation angle through a PID control algorithm.

[0020] The torque control method and system provided by this application, the control method includes determining the difference between the first target angle and the current rotation angle, wherein, the first target angle is the rotation angle executed by the electric power steering system according to the rotation angle request of the advanced driver assistance when automatically steering, and the current rotation angle is the rotation angle executed by the first torque applied to the steering wheel to control the steering wheel; calculate the second torque of the motor according to the difference, the vehicle speed, and the first torque; wherein, the second torque is the output torque of the motor. The control method provided by the embodiments of this application can calculate the output torque of the motor according to the first target angle, the current rotation angle, the vehicle speed, and the first torque. When there is a driver intervention takeover in the advanced driver assistance, it can greatly reduce the resistance between the steering motor and the driver during automatic driving and the sense of jerk during intervention, make the driver's hand feel smoother during the transition, and at the same time ensure the corner control accuracy of automatic steering. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of this application, the following will briefly introduce the drawings required in the embodiments. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0022] Figure 1 is a schematic flowchart of the torque control method provided by the embodiments of this application;

[0023] Figure 2 It is a schematic diagram of the steering wheel rotation angle during the takeover process provided by the embodiment of the present application;

[0024] Figure 3 It is one of the schematic flowcharts for calculating the second torque provided by the embodiment of the present application;

[0025] Figure 4 It is a relationship curve between the torque compensation coefficient and the first torque provided by the embodiment of the present application;

[0026] Figure 5 It is a schematic diagram of the curve of the vehicle speed compensation coefficient provided by the embodiment of the present application;

[0027] Figure 6 It is another schematic flowchart for calculating the second torque provided by the embodiment of the present application;

[0028] Figure 7 It is a structural block diagram of the torque control system provided by the embodiment of the present application.

[0029] Illustration marks:

[0030] 100 - Torque control system; 101 - Acquisition module; 102 - Determination module; 103 - Calculation module. Detailed implementation manners

[0031] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all embodiments. Based on the embodiments of the present application, other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0032] Hereinafter, terms such as "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0033] In addition, in the present application, orientation terms such as "upper", "lower", "inner", "outer", etc. are defined relative to the orientation of the components shown in the accompanying drawings. It should be understood that these directional terms are relative concepts, which are used for relative description and clarification, and they may change accordingly with the change of the orientation of the components placed in the accompanying drawings.

[0034] Currently, advanced autonomous driving is widely applied in the automotive industry. During autonomous driving, the lateral control of the vehicle is achieved in two ways: the Advanced Driving Assistance System (ADAS) controller sends a target steering wheel torque or a target steering wheel (or wheel) angle signal to the Electric Power Steering (EPS) system, and the electric power steering performs the steering action. Among them, the method of steering according to the target steering wheel torque has a lower control accuracy, but the driver's intervention feel is smoother. While the method of steering according to the target steering wheel (or wheel) angle has a higher control accuracy, but the driver's intervention feel is stiffer. Therefore, it is necessary to meet the improvement of the driver's intervention feel while achieving the control accuracy.

[0035] Generally, during automatic steering, when the driver intervenes in steering, the electric power steering system detects the hand force of the driver operating the steering wheel through a torque sensor. When the hand force value is greater than the threshold and remains for more than a certain period of time, the steering system exits the execution of the ADAS control and switches to manual steering, and the EPS provides steering assistance. Since during automatic steering, when the driver's intervention hand force increases but does not reach the switching condition stage, the EPS always performs the automatic steering action, and the assist motor always has an obvious resistance force against the driver. When switching to assist steering when reaching the threshold, the hand force will quickly decrease, causing an obvious sense of jerk and a poor driving experience.

[0036] To solve the above technical problems, an embodiment of the present application provides a torque control method, which is applied to a vehicle with advanced driving assistance. This control method can control the output torque of the motor according to the current angle of the steering wheel, the vehicle speed, and the first torque received by the steering wheel. It can gradually reduce the corrective force of the motor as the driver's hand force increases. When it is determined that the driver is driving, the motor correction is completely stopped and switched to driver driving. This control method can significantly reduce the resistance between the steering motor and the driver during autonomous driving and the sense of jerk during intervention, and at the same time ensure the corner control accuracy of automatic steering.

[0037] Figure 1 It is a schematic flowchart of the torque control method provided by the embodiment of the present application.

[0038] See Figure 1 , the torque control method provided by the embodiment of the present application is implemented by the following steps S100 to step S200.

[0039] Step S100: Determine the difference between the first target angle and the current turning angle.

[0040] Among them, the first target angle is the target angle executed by the electric power steering system according to the cornering request of the advanced driver assistance when automatically steering. The current corner is the true included angle between the wheel and the front of the vehicle when the first torque is applied to the steering wheel.

[0041] Figure 2 It is a schematic diagram of the steering wheel rotation angle during the takeover process provided by the embodiment of the present application.

[0042] See Figure 2 , taking the front of the vehicle as the Y-axis and the horizontal direction as the X-axis as an example for introduction. Among them, turning from the Y-axis to the X-axis can be understood as the vehicle turning right. L1, L2, and L3 are the straight lines where the wheels are located during the turning process.

[0043] Specifically, during automatic steering, when a cornering operation is required, the advanced driver assistance (ADAS) will send a cornering request to the electric power steering system (EPS). The engine of the advanced driver assistance (ADAS) will generate a torque T in the clockwise S direction motor -ADAS, and the electric power steering system (EPS) will execute the first target angle θ according to the current driving information target_ADAS .

[0044] When there is a driver takeover, the driver will apply a first torque T in the counterclockwise N direction on the steering wheel driver , and the steering wheel will generate a rotation angle of the actual angle θ real . Among them, the first target angle θ target_ADAS is the included angle between the straight line L1 and the Y-axis. The current corner θ real is the included angle between the straight line L2 and the Y-axis. The clockwise S direction can be the direction of rotation from the Y-axis to the X-axis, and the counterclockwise N direction can be the direction of rotation from the X-axis to the Y-axis. Of course, the X-axis, Y-axis, clockwise S direction, and counterclockwise N direction in the embodiment of the present application are only examples and are not specifically limited.

[0045] In a specific implementation, the first torque T driver can be the torque of the driver operating the steering wheel collected by the steering wheel torque sensor, and this torque can be transmitted to the electronic control unit of the electric power steering system in the form of SENT or PWM signals. The current corner θ real can be the current rotation angle of the steering wheel collected by the steering wheel angle sensor, and this angle parameter can be transmitted to the electronic control unit of the electric power steering system in the form of SENT or PWM signals. Of course, the first torque T driver and the current corner θ real can also be obtained through a composite sensor with an integrated function. No specific limitation is made here.

[0046] In step S100, the first target angle θtarget_ADAS The difference θ real from the current corner angle θ error_ADAS is the included angle between the straight line L1 and the straight line L2.

[0047] Step S200: Calculate the second torque of the motor according to the difference, vehicle speed, and first torque. Among them, the second torque of the motor is the output torque of the motor.

[0048] In the embodiment of the present application, the second torque is negatively correlated with the difference, positively correlated with the vehicle speed, and negatively correlated with the first torque.

[0049] That is to say, when the difference between the first target angle and the current corner angle is large, it means that the steering amplitude of the driver's manual operation is large at this time, and the motor needs to output a smaller second torque to reduce the resistance against the driver. When the difference between the first target angle and the current corner angle is small, it means that the steering amplitude of the driver's manual operation is small at this time, and the motor can output a larger second torque.

[0050] When the vehicle speed is fast, in order to avoid the influence of too large a corner angle on driving safety, the allowable corner angle of the steering wheel is small, and the motor can be controlled to output a larger second torque. When the vehicle speed is slow, a larger corner operation can be performed, and a smaller second torque can be output.

[0051] When the first torque is large, it means that the hand force of the driver controlling the steering wheel is large, and the resistance of the motor against the driver can be reduced, and a smaller second torque is output at this time. When the first torque is small, it means that the hand force of the driver controlling the steering wheel is small, and the motor can output a larger second torque.

[0052] It should be noted that, according to the previous automatic steering control method, the motor completely outputs the motor torque according to the difference between the first target angle θ target_ADAS and the current corner angle θ real to control the steering wheel to rotate to the position of the straight line L1. At this time, the larger the difference between the first target angle θ target_ADAS and the current corner angle θ real , the larger the output torque of the motor, and the greater the generated resistance, resulting in a poor feel for the driver.

[0053] In the embodiment of the present application, it is proposed to comprehensively consider the actually required torque output by the motor according to three factors: the difference, vehicle speed, and first torque, so as to control the output of an appropriate second torque on the premise of improving the control accuracy, so as to improve the takeover feel of the driver.

[0054] Figure 3 is one of the flow schematic diagrams for calculating the second torque provided by the embodiment of the present application.

[0055] See Figure 3 In some feasible implementations, the calculation process of the second torque can be implemented by the following steps S201 and S202.

[0056] Step S201: Calculate the target corner tolerance according to the difference, vehicle speed, and first torque.

[0057] In step S201, calculate the target corner tolerance θ error_EPS mainly to improve the control accuracy after the driver intervenes and takes over. Among them, the target corner tolerance θ error_EPS can represent the angular deviation that the steering wheel can generate from the first target angle θ target_ADAS when the driver intervenes and takes over, so as to facilitate the subsequent calculation of the second torque.

[0058] Continue to refer to Figure 2 The target corner tolerance θ error_EPS is the included angle between the straight line L1 and the straight line L3.

[0059] Specifically, the target corner tolerance θ error_EPS can be calculated using formula 1.

[0060] θ error_EPS = K1·K2·θ error_ADAS ;

[0061] Among them, θ error_EPS is the target corner tolerance, θ error_ADAS is the difference between the first target angle and the current corner, K1 is the torque compensation coefficient, and K2 is the vehicle speed compensation coefficient; among them, within the first preset interval, the torque compensation coefficient K1 is positively correlated with the first torque T driver applied to the steering wheel; within the second preset interval, the vehicle speed compensation coefficient K2 is negatively correlated with the vehicle speed V vehicle .

[0062] In a specific implementation, the target corner tolerance θ error_EPS can be calculated by the electronic control unit of the electric power steering system.

[0063] Figure 4 The relationship curve between the torque compensation coefficient provided in the embodiments of the present application and the first torque.

[0064] See Figure 4 In the first preset interval, the torque compensation coefficient K1 is positively correlated with the first torque T driver received by the steering wheel. The horizontal axis can be the first torque T driver, the torque value on the horizontal axis is related to the hand force applied by the driver to the steering wheel. The greater the hand force applied by the driver to the steering wheel, the greater the torque value on the horizontal axis. The vertical axis can be the torque compensation coefficient K1.

[0065] Specifically, the first preset interval can be [0, T driver_max , T driver_max can be the upper limit value of the first torque applied to the steering wheel. That is to say, within the interval [0, T driver_max , the greater the hand force applied by the driver to the steering wheel, the greater the torque compensation coefficient K1, until the hand force applied by the driver to the steering wheel reaches the upper limit value, causing the steering wheel to bear the upper limit value T driver_max When, the torque compensation coefficient K1 also reaches the upper limit value K 1_max . And in the part outside the first interval, the torque compensation coefficient K1 no longer changes.

[0066] Among them, Figure 4 The curve in can be calibrated according to the vehicle parameters. By setting T driver_max and K 1_max , it can be used to prevent the driver's hand force from being unable to reach the automatic steering and exiting the hand force threshold.

[0067] Figure 5 is a schematic diagram of the curve of the vehicle speed compensation coefficient provided by the embodiment of the present application.

[0068] See Figure 5 , within the second preset interval, the vehicle speed compensation coefficient K2 is negatively correlated with the vehicle speed V vehicle . The horizontal axis can be the vehicle speed V vehicle , the vehicle speed V vehicle can be calibrated for the whole vehicle. The vertical axis can be the vehicle speed compensation coefficient K2.

[0069] Specifically, the second preset interval can be [0, V vehicle_max , V vehicle_max can be the upper limit value of the vehicle speed V vehicle . Since the larger the value of the vehicle speed V vehicle , the smaller the allowable steering angle of the steering wheel, and the allowable error needs to be reduced. Therefore, within the interval [0, V vehicle_max , the larger the value of the vehicle speed V vehicle , the smaller the vehicle speed compensation coefficient K2, until the vehicle speed V vehicle reaches the upper limit value V vehicle_max When, the vehicle speed compensation coefficient K2 reaches the lower limit value K 2_min . And in the part outside the second interval, the vehicle speed compensation coefficient K2 no longer changes.

[0070] Among them, Figure 5 The curve in can be calibrated according to the vehicle parameters. Set V vehicle_max and K2_min to prevent the phenomenon that when driving at a high speed, the driver intervenes in driving and the automatic steering accuracy is too low.

[0071] In this way, through Figure 4 the corresponding torque compensation coefficient K1 can be obtained according to the first torque T applied by the driver on the steering wheel driver and through Figure 5 the corresponding vehicle speed compensation coefficient K2 can be obtained according to the vehicle speed V of the whole vehicle vehicle and then through Formula 1, the target corner tolerance θ can be calculated. error_EPS .

[0072] Step S202: Calculate the second torque of the motor according to the target corner tolerance.

[0073] Figure 6 is the second schematic diagram of the process for calculating the second torque provided by the embodiment of the present application.

[0074] Referring to Figure 6 , the process of calculating the second torque according to the target corner tolerance θ error_EPS can be realized by steps S2021 to S2023.

[0075] Step S2021: Calculate the second target angle according to the first target angle and the target corner tolerance; wherein, the second target angle is the target angle executed by the electric power steering system according to the first torque request after the driver takes over.

[0076] Exemplarily, the greater the first torque T applied by the driver on the steering wheel driver , the greater the second target angle θ tarage_EPS to be executed; the smaller the first torque T applied by the driver on the steering wheel driver , the smaller the second target angle θ tarage_EPS to be executed.

[0077] Continuing to refer to Figure 2 , the difference between the first target angle θ target_ADAS and the target corner tolerance θ error_EPS is the included angle between the straight line L3 and the Y-axis, that is, the second target angle θ tarage_EPS .

[0078] In a specific implementation, the second target angle θ tarage_EPS can be calculated by the electronic control unit of the electric power steering system.

[0079] Step S2022: Determine the takeover state of the electric power steering system according to the relationship between the first target angle and the second target angle.

[0080] In step S2022, the takeover states of the electric power steering system include advanced assisted driving takeover and driver takeover. If it is determined according to the relationship between the first target angle θ target_ADAS and the second target angle θ tarage_EPS that the takeover state remains the advanced assisted driving takeover, the motor will output at full power. When it is determined that the takeover state is driver takeover, the motor reduces its output.

[0081] Specifically, when the difference between the first target angle θ target_ADAS and the second target angle θ tarage_EPS is zero, that is, when the target steering angle tolerance θ error_EPS is zero, it means that the driver's hand force is zero at this time, that is, the first torque T driver received by the steering wheel is zero. The first target angle θ target_ADAS is equal to the second target angle θ tarage_EPS , and at this time, no steering angle deviation is allowed, and the motor outputs at full power, still maintaining the advanced assisted driving takeover state.

[0082] When the first target angle θ target_ADAS is greater than the second target angle θ tarage_EPS , that is, when the target steering angle tolerance θ error_EPS is greater than zero, at this time, steering angle deviation is allowed, and the motor will reduce its output, thereby reducing the resistance to the driver's operation.

[0083] Step S2023: In response to the takeover state being driver takeover, calculate the second torque of the motor according to the second target angle and the current steering angle.

[0084] When it is determined that the takeover is by the driver, since the current steering angle θ real is the angle between the straight line L2 and the Y-axis, and the second target angle θ tarage_EPS is the angle between the straight line L3 and the Y-axis, then it is only necessary to control the steering wheel to rotate from θ real to θ tarage_EPS . In this way, the electric power steering system can use the angle difference between the second target angle θ tarage_EPS and the current steering angle θ real as a feedback parameter, and specifically, the second torque of the motor can be calculated through the PID (Proportion, Integral, Differential) control algorithm.

[0085] Specifically, the torque control method provided in the embodiments of the present application can calculate the output torque of the motor according to the vehicle speed, the current steering angle received by the steering wheel, and the first torque and the first target angle. When there is driver intervention during advanced assisted driving, it can greatly reduce the resistance between the steering motor and the driver during automatic driving and the sense of jerk during intervention, making the driver's hand feel smoother, and at the same time, it can ensure the steering angle control accuracy of automatic steering.

[0086] Corresponding to the embodiments of the foregoing torque control method, the present application also provides embodiments of a torque control system.

[0087] Figure 7 It is a structural block diagram of the torque control system provided by the embodiments of the present application.

[0088] See Figure 7 , the torque control system 100 includes an acquisition module 101, a determination module 102, and a calculation module 103.

[0089] The acquisition module 101 can be used to acquire a first target angle θ in advanced assisted driving tarage_ADAS ; wherein, the first target angle θ tarage_ADAS is the target angle executed by the electric power steering system according to the steering angle request of advanced assisted driving during automatic steering. The acquisition module 101 can also be used to acquire, during the process of advanced assisted driving, the first torque T received by the electric power steering system driver and the current steering angle θ of the steering wheel rotation real , the current steering angle θ real is the steering angle executed by the T driver to control the steering wheel under the condition of the first torque applied by the driver to the steering wheel, and the current steering angle θ real is the true included angle between the wheel and the front of the vehicle.

[0090] That is to say, the acquisition module 101 can be used to acquire the first target angle θ tarage_ADAS , the current steering angle θ real and the first torque T driver .

[0091] In a specific implementation, the acquisition module 101 can include an angle sensor, and the first target angle θ tarage_ADAS and the current steering angle θ real can be acquired through the angle sensor. The acquisition module 101 can also include a torque sensor, and the first torque T applied to the steering wheel driver can be acquired through the torque sensor.

[0092] The determination module 102 can be used to determine the difference between the first target angle θ tarage_ADAS and the current steering angle θ real .

[0093] That is to say, the determination module 102 can be used to execute step S100 in the above-mentioned embodiment of the control method.

[0094] The calculation module 103 can be used to calculate according to the difference, the vehicle speed V vehicle , the first torque T driver, calculate the second torque of the motor; wherein, the second torque is the output torque of the motor, the second torque is negatively correlated with the difference value, the second torque is positively correlated with the vehicle speed, and the second torque is negatively correlated with the first torque.

[0095] That is to say, the calculation module 103 can be used to execute step S200 in the above-mentioned control method embodiment.

[0096] In some feasible implementations, the calculation module 103 can calculate the target corner tolerance θ error_ADAS through the difference value θ vehicle , vehicle speed V driver , and the first torque T error_EPS ; and then calculate the second torque of the motor according to the target corner tolerance θ error_EPS .

[0097] Wherein, in the process of calculating the target corner tolerance θ error_EPS , the formula 1 can be used to calculate the target corner tolerance θ error_EPS , and the formula 1 is:

[0098] θ error_EPS =K1·K2·θ error_ADAS ;

[0099] Wherein, θ error_EPS is the target corner tolerance, θ error_ADAS is the difference between the first target angle and the current angle, K1 is the torque compensation coefficient, and K2 is the vehicle speed compensation coefficient; within the first preset interval, the torque compensation coefficient K1 is positively correlated with the first torque T driver ; within the second preset interval, the vehicle speed compensation coefficient K2 is negatively correlated with the vehicle speed V vehicle .

[0100] And in the process of calculating the second torque of the motor through the target corner tolerance θ error_EPS , the calculation module 103 can also calculate the second target angle θ tarage_ADAS according to the first target angle θ error_EPS and the target corner tolerance θ tarage_EPS ; wherein, the second target angle θ tarage_EPS is the target angle requested by the electric power steering system according to the first torque T driver ; determine the takeover state according to the relationship between the first target angle θ tarage_ADAS and the second target angle θ tarage_EPS ; in response to the takeover state being driver takeover, calculate the second torque of the motor according to the second target angle θ tarage_EPS and the current angle.

[0101] Specifically, the calculation module 103 can use the PID control algorithm to calculate according to the second target angle θ tarage_EPS and the current angle θreal The difference is used to calculate the second torque of the motor.

[0102] In a specific implementation, the calculation module 103 can be an Electronic Control Unit (ECU).

[0103] Specifically, the torque control system provided by the embodiments of the present application can calculate the output torque of the motor according to the first target angle θ tarage_ADAS , the current rotation angle θ real , the vehicle speed V vehicle and the first torque T driver When there is driver intervention and takeover in advanced assisted driving, it can significantly reduce the resistance between the steering motor and the driver during automatic driving and the sense of jerk during intervention, making the driver's hand feel smoother during the transition, and at the same time ensuring the corner control accuracy of automatic steering.

[0104] It should be noted that those skilled in the art will readily think of other implementation manners of the present application after considering the specification and the practice of the application disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include the common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and the embodiments are only regarded as exemplary, and the true scope of the present application is pointed out by the claims.

[0105] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A torque control method, characterized in that, Including: Determine the difference between the first target angle and the current steering angle, where the first target angle is the target angle executed by the electric power steering system according to the steering angle request of the advanced driver assistance during automatic steering, and the current steering angle is the actual angle between the wheel and the front of the vehicle when the driver applies the first torque to the steering wheel; Calculate the second torque of the motor according to the difference, vehicle speed, and the first torque; where the second torque is the output torque of the motor, the second torque is negatively correlated with the difference, the second torque is positively correlated with the vehicle speed, and the second torque is negatively correlated with the first torque.

2. The torque control method according to claim 1, wherein: The calculating the second torque of the motor according to the difference, vehicle speed, and the first torque includes: Calculate the target steering angle tolerance according to the difference, vehicle speed, and the first torque; Calculate the second torque of the motor according to the target steering angle tolerance.

3. The torque control method according to claim 2, wherein: The calculating the second torque of the motor according to the target steering angle tolerance includes: Calculate the second target angle according to the first target angle and the target steering angle tolerance; where the second target angle is the target angle executed by the electric power steering system according to the first torque request; Determine the takeover state according to the relationship between the first target angle and the second target angle; In response to the takeover state being taken over by the driver, calculate the second torque of the motor according to the second target angle and the current steering angle.

4. The torque control method according to claim 2, wherein: The calculating the target steering angle tolerance according to the difference, vehicle speed, and the first torque includes: Calculate the target steering angle tolerance using formula 1, and formula 1 is: θ error_EPS = K1·K2·θ error_ADAS ; Among them, θ error_EPS is the target corner tolerance value, θ error_ADAS is the difference between the first target angle and the current corner angle, K1 is the torque compensation coefficient, and K2 is the vehicle speed compensation coefficient; within the first preset interval, the torque compensation coefficient is positively correlated with the first torque; within the second preset interval, the vehicle speed compensation coefficient is negatively correlated with the vehicle speed.

5. The torque control method according to claim 3, wherein: The calculating the second torque of the motor according to the second target angle and the current steering angle includes: Calculate the second torque of the motor according to the second target angle and the current steering angle through the PID control algorithm.

6. A torque control system, characterized in that, Including: A determination module configured to determine the difference between the first target angle and the current steering angle, where the first target angle is the target angle executed by the electric power steering system according to the steering angle request of the advanced driver assistance during automatic steering, and the current steering angle is the actual angle between the wheel and the front of the vehicle when the driver applies the first torque to the steering wheel; A calculation module configured to calculate the second torque of the motor according to the difference, vehicle speed, and the first torque; where the second torque is the output torque of the motor, the second torque is negatively correlated with the difference, the second torque is positively correlated with the vehicle speed, and the second torque is negatively correlated with the first torque.

7. The torque control system according to claim 6, wherein: The calculation module is further configured to calculate the target steering angle tolerance according to the difference, vehicle speed, and the first torque; calculate the second torque of the motor according to the target steering angle tolerance.

8. The torque control system according to claim 7, wherein: The calculation module is further configured to calculate a second target angle according to the first target angle and the target rotation angle tolerance value; wherein, the second target angle is the target angle executed by the electric power steering system according to the first torque request; determine the takeover state according to the relationship between the first target angle and the second target angle; in response to the takeover state being a driver takeover, calculate the second torque of the motor according to the second target angle and the current rotation angle.

9. The torque control system according to claim 8, wherein the calculation module is further configured to calculate the target rotation angle tolerance value by using Formula 1, and the Formula 1 is: θ error_EPS = K1·K2·θ error_ADAS ; where θ error_EPS is the target corner tolerance value, θ error_ADAS is the difference between the first target angle and the current corner angle, K1 is the torque compensation coefficient, and K2 is the vehicle speed compensation coefficient; within the first preset interval, the torque compensation coefficient is positively correlated with the first torque; within the second preset interval, the vehicle speed compensation coefficient is negatively correlated with the vehicle speed.

10. The torque control system according to claim 8, wherein the determination module is further configured to calculate the second torque of the motor according to the second target angle and the current rotation angle through a PID control algorithm.

Images