Compensation method and system of steer-by-wire system, storage medium and vehicle

Abstract

The invention provides a compensation method and system of a steer-by-wire system, a storage medium and a vehicle, and belongs to the technical field of vehicles, and the compensation method of the steer-by-wire system comprises the steps that based on the first temperature of lubricating grease of a simulation unit at the current moment and the second temperature of lubricating grease of a steering unit at the current moment, the first temperature of the lubricating grease of the simulation unit at the current moment is calculated; determining a target unit to be compensated, wherein the temperature of lubricating grease in the target unit at the current moment is lower than a temperature threshold value; compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment; and controlling the torque output by the simulation unit based on the compensated target force. According to the invention, through a force compensation mode, the additionally increased road feeling simulation torque due to the increase of the viscosity of the lubricating grease of the steer-by-wire system is eliminated, and the authenticity of the road feeling simulated by the simulation unit in a low-temperature environment is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a compensation method, system, storage medium and vehicle for a wire-controlled steering system. Background Art

[0002] A steer-by-wire system is a steering system that performs steering control through signal transmission. In a steer-by-wire system, there is no mechanical connection between the steering wheel column and the tie rod, and the steering motor drives the tie rod to move based on the steering wheel angle collected by the steering wheel angle sensor. Since there is no mechanical connection between the steering wheel column and the tie rod, the steering wheel column cannot receive feedback from the tie rod or the wheel, resulting in the driver being unable to perceive the road surface through the steering wheel.

[0003] In the related art, in order to ensure the driver's road feel, a road feel simulation unit (also called a hand feel simulation unit) is usually set in the wire steering system to simulate the road feel. However, when the vehicle is in a low temperature environment, the viscosity of the lubricating grease of each unit in the wire steering system will increase, which will cause the road feel fed back to the driver by the road feel simulation unit to become heavy and unable to fully restore the real road feel. Summary of the invention

[0004] Based on this, the present application provides a compensation method, system, storage medium and vehicle for a steer-by-wire system to solve the problem of how to improve the authenticity of the road feel simulated by a road feel simulation unit in a low temperature environment.

[0005] According to a first aspect of an embodiment of the present application, a compensation method for a steer-by-wire system is provided, wherein the steer-by-wire system comprises a simulation unit and a steering unit, wherein the steering unit is configured to drive a wheel to deflect, and the simulation unit is configured to output torque to a steering wheel to simulate a road feel, wherein the method comprises: respectively obtaining a first temperature of the lubricating grease of the simulation unit at the current moment and a second temperature of the lubricating grease of the steering unit at the current moment; Based on the first temperature and the second temperature, determining a target unit to be compensated, the target unit comprising at least one of the simulation unit and the steering unit, and the temperature of lubricating grease in the target unit at the current moment is lower than a temperature threshold; Compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment; Based on the compensated target force, the torque output by the simulation unit is controlled.

[0006] Optionally, the steering unit includes a steering rack, and when the target unit includes the steering unit, compensating the target force of the target unit based on the temperature of lubricating grease of the target unit at the current moment includes: Obtaining the actual rack force applied to the steering rack at the current moment; determining a first compensation coefficient based on the second temperature; Based on the first compensation coefficient, the actual rack force is compensated to obtain a basic compensation force of the simulation unit; The step of controlling the torque output by the simulation unit based on the compensated target force includes: Based on the basic compensation force, the torque output by the simulation unit is controlled.

[0007] Optionally, the steering unit includes a steering rack, and when the target unit includes the simulation unit and the steering unit, compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment includes: Obtaining the actual rack force applied to the steering rack at the current moment; determining a second compensation coefficient based on the first temperature, and determining a first compensation coefficient based on the second temperature; Based on the first compensation coefficient, the actual rack force is compensated to obtain a basic compensation force of the simulation unit; Compensating the basic compensation force based on the second compensation coefficient; The step of controlling the torque output by the simulation unit based on the compensated target force includes: Based on the compensated basic compensation force, the torque output by the simulation unit is controlled.

[0008] Optionally, at a preset time after the current time, determining a first compensation coefficient based on the second temperature includes: Acquire the accumulated travel of the steering rack, where the accumulated travel is the sum of the movement travel of the steering rack between the current moment and the preset moment; determining a first sub-coefficient based on the second temperature, and determining a second sub-coefficient based on the accumulated travel distance; The first compensation coefficient is determined based on the first sub-coefficient and the second sub-coefficient.

[0009] Optionally, the simulation unit includes a first component, and the distance between the lubricating grease of the simulation unit and the first component is less than a first preset distance; the steering unit includes a second component, and the distance between the lubricating grease of the steering unit and the second component is less than a second preset distance; and respectively obtaining a first temperature of the lubricating grease of the simulation unit at a current moment, and a second temperature of the lubricating grease of the steering unit at the current moment, comprises: respectively acquiring the temperature of the first component and the second component at the current moment; The first temperature is determined based on the temperature of the first component at the current moment, and the second temperature is determined based on the temperature of the second component at the current moment.

[0010] Optionally, before determining the target unit to be compensated based on the first temperature and the second temperature, the method further includes: Determining whether the first temperature and the second temperature are both valid values; The determining a target unit to be compensated based on the first temperature and the second temperature includes: In a case where both the first temperature and the second temperature are valid values, a target unit to be compensated is determined based on the first temperature and the second temperature.

[0011] Optionally, the method further comprises: When the first temperature and / or the second temperature is an invalid value, controlling the torque output by the simulation unit based on the state parameter of the steering wheel at the current moment and the driving speed of the vehicle at the current moment; Wherein, the state parameters include steering wheel speed, steering wheel torque and steering wheel angle.

[0012] According to a second aspect of an embodiment of the present application, a compensation system for a steer-by-wire system is provided, wherein the steer-by-wire system comprises a simulation unit and a steering unit, wherein the steering unit is configured to drive a wheel to deflect, and the simulation unit is configured to output torque to a steering wheel to simulate a road feel, and the compensation system comprises: an acquisition unit, used to respectively acquire a first temperature of the lubricating grease of the simulation unit at a current moment, and a second temperature of the lubricating grease of the steering unit at the current moment; a determining unit, configured to determine a target unit to be compensated based on the first temperature and the second temperature, wherein the target unit includes at least one of the simulation unit and the steering unit, and the temperature of the lubricating grease in the target unit at the current moment is lower than a temperature threshold; A compensation unit, configured to compensate a target force of the target unit based on a temperature of lubricating grease of the target unit at the current moment; The execution unit is used to control the torque output by the simulation unit based on the compensated target force.

[0013] According to a third aspect of an embodiment of the present application, a computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the steps of the compensation method for the wire-controlled steering system described in the second aspect of the present application are implemented.

[0014] A fourth aspect of the embodiments of the present application provides a vehicle comprising the compensation system of the wire-controlled steering system described in the second aspect of the embodiments of the present application, or comprising a control module, wherein the control module is used to implement the steps of the compensation method of the wire-controlled steering system described in the first aspect of the embodiments of the present application.

[0015] The present application provides a compensation method, system, storage medium and vehicle for a wire-controlled steering system, the method comprising: respectively obtaining a first temperature of the lubricant of the simulation unit at a current moment, and a second temperature of the lubricant of the steering unit at the current moment; determining a target unit to be compensated based on the first temperature and the second temperature, the target unit comprising at least one of the simulation unit and the steering unit, and the temperature of the lubricant in the target unit at the current moment is lower than a temperature threshold; compensating for a target force of the target unit based on the temperature of the lubricant of the target unit at the current moment; and controlling the torque output by the simulation unit based on the compensated target force.

[0016] The present application first obtains the temperature of the lubricating grease of the simulation unit and the steering unit at the current moment, and determines at least one of the simulation unit and the steering unit whose lubricating grease temperature at the current moment is lower than the temperature threshold as the target unit, and then compensates the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment. Finally, based on the compensated target force, the torque output by the simulation unit is controlled. The present application determines the target unit that needs to be compensated for the target force by the temperature of the lubricating grease, and compensates the target force according to the temperature of the lubricating grease. Afterwards, the torque output by the simulation unit is controlled according to the compensated target force, thereby eliminating the additional road feel simulation torque due to the increased viscosity of the lubricating grease of the wire-controlled steering system through compensation, thereby improving the authenticity of the road feel simulated by the simulation unit in a low temperature environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0018] Figure 1 is a step diagram of a compensation method for a wire-controlled steering system provided in an embodiment of the present application; Figure 2 This is a step diagram of a method for compensating a steering unit provided in an embodiment of the present application; Figure 3 It is a step diagram of a method for compensating a steering unit and a simulation unit provided in an embodiment of the present application; Figure 4 is a step diagram of a method for determining a first compensation coefficient provided in an embodiment of the present application; Figure 5 This is a step diagram of a method for obtaining a first temperature and a second temperature provided in an embodiment of the present application; Figure 6 is a flow chart of a compensation method for a wire-controlled steering system provided in an embodiment of the present application; Figure 7 It is a structural schematic diagram of a compensation system of a wire-controlled steering system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0020] A steer-by-wire system is a steering system that performs steering control through signal transmission. In a steer-by-wire system, there is no mechanical connection between the steering wheel column and the tie rod, and the steering motor drives the tie rod to move based on the steering wheel angle collected by the steering wheel angle sensor. Since there is no mechanical connection between the steering wheel column and the tie rod, the steering wheel column cannot receive feedback from the tie rod or the wheel, resulting in the driver being unable to perceive the road surface through the steering wheel.

[0021] In the related art, in order to ensure the driver's road feel, a road feel simulation unit (also called a hand feel simulation unit) is usually set in the wire steering system to simulate the road feel. However, when the vehicle is in a low temperature environment, the viscosity of the lubricating grease of each unit in the wire steering system will increase, which will cause the road feel fed back to the driver by the road feel simulation unit to become heavy and unable to fully restore the real road feel.

[0022] Based on this, in order to solve the problem of how to improve the authenticity of the road feel simulated by the road feel simulation unit in a low temperature environment, the present application provides a compensation method, system, storage medium and vehicle for a wire-controlled steering system, firstly obtaining the temperature of the lubricating grease of the simulation unit and the steering unit at the current moment, and determining at least one of the simulation unit and the steering unit whose lubricating grease temperature at the current moment is lower than the temperature threshold as the target unit, and then compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment. Finally, based on the compensated target force, the torque output by the simulation unit is controlled. In this embodiment, the target unit that needs to be compensated for the target force is determined by the temperature of the lubricating grease, and the target force is compensated according to the temperature of the lubricating grease. Afterwards, the torque output by the simulation unit is controlled according to the compensated target force, thereby eliminating the additional road feel simulation torque due to the increase in the viscosity of the lubricating grease of the wire-controlled steering system through force compensation, thereby improving the authenticity of the road feel simulated by the simulation unit in a low temperature environment. The specific method is as follows: The first aspect of the present application proposes an embodiment, such as Figure 1 As shown in the step diagram of a compensation method for a wire-controlled steering system, the method is applicable to the wire-controlled steering system of a vehicle, and specifically to the controller of the wire-controlled steering system.

[0023] The steer-by-wire system includes a simulation unit and a steering unit. The simulation unit includes a road feel simulation motor, a reducer, etc. The output shaft of the road feel simulation motor is connected to the steering wheel through the reducer. When the driver turns the steering wheel, the road feel simulation motor outputs a torque in the opposite direction of the steering wheel through the reducer, so that the driver feels a resistance when turning the steering wheel. The resistance felt by the driver is the road feel, which can also be called the feel.

[0024] The steering unit is a unit used to drive the wheel to deflect. The steering unit includes a steering motor, a steering rack, etc. The output shaft of the steering motor is connected to the steering rack, and the steering rack is connected to the wheel through a tie rod. When the driver intends to steer, the steering wheel angle sensor in the wire-controlled steering system collects the steering wheel angle input by the driver and sends the steering wheel angle to the controller of the steering motor, so that the controller of the steering motor controls the output shaft of the steering motor to rotate to an angle corresponding to the steering wheel angle, thereby driving the steering rack to drive the wheel to deflect.

[0025] In a conventional road feel simulation process, the simulation unit receives the rack force borne by the steering rack during vehicle deflection, and then controls the rotation of the output shaft of the road feel simulation motor based on the rack force borne by the steering rack.

[0026] The main steps of the method described in this application include: Step S101 , respectively obtaining a first temperature of the lubricating grease of the simulation unit at the current moment and a second temperature of the lubricating grease of the steering unit at the current moment.

[0027] The simulation unit can also be called a road feel simulation unit or a hand feel simulation unit. The simulation unit is connected to the steering wheel, and the road feel simulation motor in the simulation unit outputs torque to the steering wheel, thereby simulating the road feel. In this process, the interaction of mechanical structures such as reducers is required to achieve force transmission. When the mechanical structure of the simulation unit moves relative to each other, the lubricating grease of the simulation unit can lubricate the two adjacent mechanical structures, thereby avoiding abnormal wear of the simulation unit.

[0028] The steering unit also requires interaction and mutual movement between the steering rack and the steering motor output shaft to achieve the deflection of the driving wheel. Similar to the simulation unit, the grease of the steering unit can lubricate the steering rack and the steering motor output shaft when they move against each other, thereby avoiding abnormal wear of the steering unit.

[0029] In addition, the lubricating grease of the simulation unit and the steering unit may also adhere to the surface of other mechanical structures or components. As long as the lubricating grease is located inside or outside the simulation unit and the steering unit, it is considered to be the lubricating grease of the simulation unit and the steering unit.

[0030] In an optional implementation, the temperature of the lubricating grease of the simulation unit and the steering unit at the current moment can be acquired by an infrared temperature sensor.

[0031] Step S102: determining a target unit to be compensated based on the first temperature and the second temperature.

[0032] The target unit includes at least one of the simulation unit and the steering unit, and the temperature of the lubricating grease in the target unit is lower than a temperature threshold at the current moment.

[0033] The viscosity of lubricating grease changes with its temperature. The higher the temperature of the lubricating grease, the lower the viscosity; the lower the temperature of the lubricating grease, the higher the viscosity. The higher the viscosity of the lubricating grease, the greater the viscous effect on the mechanical structure during lubrication, and the greater the resistance to the movement of the mechanical structure. Therefore, the resistance of the simulation unit and the steering unit from the lubricating grease can be determined by the temperature of the lubricating grease.

[0034] It can be seen that the first temperature and the second temperature actually represent the magnitude of the resistance from the lubricating grease to the simulation unit and the steering unit, respectively. Further, the target unit that needs force compensation can be determined based on the first temperature and the second temperature.

[0035] The target unit may be a simulation unit, or a steering unit, or a simulation unit and a steering unit. The temperature thresholds corresponding to the lubricants of different target units may be the same or different. For example, the temperature threshold corresponding to the lubricant of the simulation unit may be a first temperature threshold, and the temperature threshold corresponding to the lubricant of the steering unit may be a second temperature threshold. When the first temperature is lower than the first temperature threshold, the simulation unit may be determined as the target unit; when the second temperature is lower than the second temperature threshold, the steering unit may be determined as the target unit.

[0036] In an optional embodiment, the temperature threshold may be 5° C., or may be determined based on the composition of the lubricating grease.

[0037] Step S103 : compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment.

[0038] When the temperature of the lubricating grease of the simulation unit or the steering unit at the current moment is less than the temperature threshold, it indicates that the lubricating grease has a viscous effect on the movement of the mechanical structure of the simulation unit or the steering unit, and therefore compensation is required.

[0039] Since the lower the temperature of the lubricating grease, the greater the viscosity effect, the compensation amplitude of the target force in the target unit can be determined by the temperature of the lubricating grease of the target unit at the current moment.

[0040] Taking the target unit as the simulation unit as an example, the compensation process is briefly described. First, a table can be looked up according to the first temperature of the simulation unit to determine the first compensation torque corresponding to the first temperature. Among them, the table required for the table lookup stores different torque values ​​corresponding to different lubricating grease temperatures. Subsequently, the second compensation torque is determined based on the steering wheel torque at the current moment and the steering wheel speed at the current moment. Finally, the sum of the first compensation torque and the second compensation torque is used as the final compensation torque. After determining the compensation torque, the rack force received by the simulation unit is compensated by the compensation torque, and then the torque that the simulation unit finally outputs to the steering wheel is determined.

[0041] Step S104: controlling the torque output by the simulation unit based on the compensated target force.

[0042] After compensating the target force, the target torque corresponding to the compensated target force is determined based on the compensated target force, and the simulation unit is controlled to output the target torque, thereby achieving correction of the road feel.

[0043] This embodiment first obtains the temperature of the lubricating grease of the simulation unit and the steering unit at the current moment, and determines at least one of the simulation unit and the steering unit whose lubricating grease temperature at the current moment is lower than the temperature threshold as the target unit, and then compensates the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment. Finally, based on the compensated target force, the torque output by the simulation unit is controlled. This embodiment determines the target unit that needs to be compensated for the target force by the temperature of the lubricating grease, and compensates the target force according to the temperature of the lubricating grease. Afterwards, the torque output by the simulation unit is controlled according to the compensated target force, thereby eliminating the additional road feel simulation torque due to the increase in the viscosity of the lubricating grease of the wire-controlled steering system through force compensation, thereby improving the authenticity of the road feel simulated by the simulation unit in a low temperature environment.

[0044] Optionally, the steering unit includes a steering rack, referring to Figure 2 A method step diagram for compensating a steering unit is shown, in which, when the target unit includes the steering unit, the target force of the target unit is compensated based on the temperature of the lubricating grease of the target unit at the current moment in step S103, including: Step S11, obtaining the actual rack force applied to the steering rack at the current moment.

[0045] Step S12: determining a first compensation coefficient based on the second temperature.

[0046] Step S13: Compensating the actual rack force based on the first compensation coefficient to obtain a basic compensation force of the simulation unit.

[0047] The step S104 of controlling the torque output by the simulation unit based on the compensated target force specifically includes: Based on the basic compensation force, the torque output by the simulation unit is controlled.

[0048] The actual rack force on the steering rack at the current moment is the load force on the steering rack, and the actual rack force includes the force of the wheel on the steering rack and the force on the steering rack under the viscosity of the lubricating grease. In an optional embodiment, the actual rack force can be determined by estimation or collected by a strain sensor.

[0049] The second temperature actually characterizes the magnitude of the viscous force of the lubricant on the steering rack. Therefore, the first compensation coefficient determined based on the second temperature also characterizes the magnitude of the viscous force of the lubricant on the steering rack. Therefore, by compensating the actual rack force based on the first compensation coefficient, the force exerted on the steering rack under the viscous effect of the lubricant in the actual rack force can be eliminated, thereby making the basic compensation force obtained closer to the force exerted by the wheel on the steering rack. Finally, based on the basic compensation force obtained after compensation, the torque output by the simulation unit is controlled, so that the torque output by the simulation unit is no longer affected by the viscous force of the lubricant, thereby improving the authenticity of the road feel feedback.

[0050] In an optional embodiment, the first compensation coefficient can be determined by the correspondence between the temperature of the lubricating grease of the steering unit and the compensation coefficient. Specifically, the second temperature is matched in the above correspondence, and the compensation coefficient corresponding to the second temperature in the correspondence is determined as the first compensation coefficient.

[0051] In an optional implementation, the basic compensation force and the torque output by the simulation unit may have a linear relationship. After the basic compensation force is obtained, the target torque corresponding to the basic compensation force is determined through the aforementioned linear relationship, and then the simulation unit is controlled to output the target torque to the steering wheel.

[0052] In the present embodiment, when the target unit includes a steering unit, the actual rack force exerted on the steering rack at the current moment is first obtained, and then the portion of the actual rack force applied by the lubricating grease is determined through the second temperature, and then the portion of the actual rack force that is increased due to the lubricating grease is corrected through the first compensation coefficient determined by the second temperature, so that the torque output by the simulation unit is no longer affected by the viscosity of the lubricating grease, thereby improving the authenticity of the road feel feedback.

[0053] Optionally, the steering unit includes a steering rack, referring to Figure 3A method step diagram for compensating a steering unit and a simulation unit is shown. When the target unit includes the simulation unit and the steering unit, the target force of the target unit is compensated based on the temperature of the lubricating grease of the target unit at the current moment in step S103, which specifically includes the following steps: Step S21, obtaining the actual rack force applied to the steering rack at the current moment.

[0054] Step S22: determining a second compensation coefficient based on the first temperature, and determining a first compensation coefficient based on the second temperature.

[0055] Step S23: Compensating the actual rack force based on the first compensation coefficient to obtain a basic compensation force of the simulation unit.

[0056] Step S24: compensating the basic compensation force based on the second compensation coefficient.

[0057] The step S104 of controlling the torque output by the simulation unit based on the compensated target force specifically includes: Based on the compensated basic compensation force, the torque output by the simulation unit is controlled.

[0058] The first temperature characterizes the magnitude of the viscous force of the lubricating grease on the steering rack, and the second temperature characterizes the magnitude of the viscous force of the lubricating grease on the simulation unit. Therefore, the second compensation coefficient determined based on the first temperature also characterizes the magnitude of the viscous force of the lubricating grease on the steering rack, and the first compensation coefficient determined based on the second temperature also characterizes the magnitude of the viscous force of the lubricating grease on the simulation unit.

[0059] On this basis, when the target unit includes a simulation unit and a steering unit, it indicates that the lubricants in the simulation unit and the steering unit have a negative effect on the simulation of the road feel. Therefore, the force can be compensated in turn through the first compensation coefficient and the second compensation coefficient, so that the final compensated basic compensation force is no longer affected by the viscosity of the lubricant, and finally the torque output by the simulation unit is no longer affected by the viscosity of the lubricant.

[0060] In an optional implementation, when compensating the basic compensation force based on the second compensation coefficient, the compensation may be performed on the basis of the basic compensation force itself, or after converting the basic compensation force into a corresponding road feel simulation torque, the compensation may be performed.

[0061] In an optional embodiment, after obtaining the compensated basic compensation force, a compensation torque can be determined by looking up a table based on the current steering wheel torque and the current steering wheel speed. The compensated basic compensation force is compensated again by using the compensation torque, and finally the target torque output by the simulation unit to the steering wheel is obtained.

[0062] In an optional implementation, determining the second compensation coefficient based on the first temperature may specifically include the following steps: first determining the third sub-coefficient by the first temperature, and determining the fourth sub-coefficient by the steering wheel torque and the steering wheel speed, and then determining the second compensation coefficient by the third sub-coefficient and the fourth sub-coefficient. In addition, at a preset time after the current time, the fifth sub-coefficient may be determined by the accumulated steering angle of the steering wheel, and the second compensation coefficient may be determined based on the third sub-coefficient, the fourth sub-coefficient and the fifth sub-coefficient. The formula for determining the second compensation coefficient based on the third sub-coefficient, the fourth sub-coefficient and the fifth sub-coefficient may refer to the following formula (1):

[0063] Among them, M1 is the second compensation coefficient, T1 is the third sub-coefficient, C1 is the fifth sub-coefficient, and T2 is the fourth sub-coefficient.

[0064] In this embodiment, when the target unit includes a steering unit and a simulation unit, the first compensation coefficient and the second compensation coefficient are used to successively eliminate the influence of the viscosity of the lubricating grease in the steering unit and the simulation unit on the road feel simulation torque, so that the road feel simulation torque output by the simulation unit is no longer affected by the viscosity of the lubricating grease, thereby improving the authenticity of the road feel feedback.

[0065] Optionally, refer to Figure 4 A method step diagram for determining a first compensation coefficient is shown, wherein at a preset time after the current time, the first compensation coefficient is determined based on the second temperature in step S12 and step S22, specifically including the following steps: Step S31, obtaining the accumulated travel of the steering rack.

[0066] The accumulated stroke is the sum of the movement strokes of the steering rack between the current moment and the preset moment.

[0067] Step S32: determining a first sub-coefficient based on the second temperature, and determining a second sub-coefficient based on the accumulated travel distance.

[0068] Step S33: determining the first compensation coefficient based on the first sub-coefficient and the second sub-coefficient.

[0069] After the current moment, the steering rack will continue to move under the control of the driver, thereby controlling the deflection direction of the wheel during vehicle driving. During the movement, the steering rack will rub against other mechanical structures and lubricating grease, causing the temperature of the lubricating grease to change under the action of frictional heat.

[0070] Therefore, in order to reduce the number of temperature collection times, at a preset time after the current time, in order to adapt the first compensation coefficient to the temperature of the lubricating grease in the steering rack, the first sub-coefficient and the second coefficient can be determined respectively through the second temperature and the accumulated travel of the steering rack, and then the first compensation coefficient can be determined based on the first sub-coefficient and the second sub-coefficient.

[0071] Referring to the calculation formula of the basic compensation force shown in formula (2), the calculation formula of the basic compensation force based on the first sub-coefficient and the second sub-coefficient is as follows:

[0072] Among them, F1 is the basic compensation force, F2 is the actual rack force, C3 is the first sub-coefficient, and C4 is the second sub-coefficient.

[0073] In an optional implementation, the preset time may be any time after the current time.

[0074] In this embodiment, at a preset moment after the current moment, the first compensation coefficient is determined by using the first sub-coefficient determined based on the second temperature and the second sub-coefficient determined based on the accumulated stroke, so that the linear steering system does not need to collect the temperature of the lubricating grease again after the current moment. The first compensation coefficient corresponding to the temperature of the lubricating grease at the preset moment can be determined by using the first sub-coefficient and the second sub-coefficient, thereby reducing the number of temperature collection times.

[0075] Optionally, the simulation unit includes a first component, the distance between the lubricating grease of the simulation unit and the first component is less than a first preset distance, the steering unit includes a second component, the distance between the lubricating grease of the steering unit and the second component is less than a second preset distance, Figure 5 A method step diagram for obtaining a first temperature and a second temperature is shown, wherein step S101 of respectively obtaining the first temperature of the lubricating grease of the simulation unit at the current moment and the second temperature of the lubricating grease of the steering unit at the current moment specifically includes the following steps: Step S41, respectively obtaining the temperatures of the first component and the second component at the current moment.

[0076] Step S42: determining the first temperature based on the temperature of the first component at the current moment, and determining the second temperature based on the temperature of the second component at the current moment.

[0077] The first component may be any component in the simulation unit whose distance from the lubricating grease of the simulation unit is less than the first preset distance, and the second component may be any component in the steering unit whose distance from the lubricating grease of the steering unit is less than the second preset distance. In an optional embodiment, the first preset distance and the second preset distance may be fixed values, or may be determined according to the heat radiation range of the lubricating grease of the simulation unit and the steering unit, respectively.

[0078] When the distance between the first component and the lubricating grease of the simulation unit is less than the first preset distance, it indicates that the temperature of the first component is greatly affected by the lubricating grease of the simulation unit. Therefore, the temperature of the lubricating grease of the simulation unit can be inferred based on the temperature of the first component.

[0079] Similarly, when the distance between the second component and the lubricating grease of the steering unit is less than the first preset distance, it indicates that the temperature of the second component is greatly affected by the lubricating grease of the steering unit. Therefore, the temperature of the lubricating grease of the steering unit can be inferred based on the temperature of the second component.

[0080] The temperatures of the first component and the second component at the current moment can be collected by a temperature sensor. After collecting the temperature of the first component at the current moment, the temperature of the first component at the current moment can be corrected by a temperature correction coefficient to obtain a first temperature. Similarly, after collecting the temperature of the second component at the current moment, the temperature of the second component at the current moment can also be corrected by a temperature correction coefficient to obtain a second temperature. The temperature correction coefficient can be a preset value preset in the controller of the linear steering system and determined by a technician through test data.

[0081] In an optional embodiment, the first component may be a control board of the simulation unit, and the second component may be a control board of the steering unit.

[0082] This embodiment indirectly determines the first temperature and the second temperature through the temperatures of the first component and the second component at the current moment, which can avoid direct collection of the lubricant temperature, thereby reducing the technical difficulty of implementing the lubricant temperature collection and reducing the technology and manufacturing costs required to implement the method described in this application.

[0083] Optionally, before determining the target unit to be compensated based on the first temperature and the second temperature in step S102, the method further includes: Step S105: determining whether the first temperature and the second temperature are both valid values.

[0084] When both the first temperature and the second temperature are valid values, the process proceeds to step S102 .

[0085] The effective value refers to a value that can reflect the real value. The first temperature is an effective value, which means that the first temperature obtained can reflect the real temperature of the lubricating grease of the simulation unit at the current moment, and the second temperature is an effective value, which means that the second temperature obtained can reflect the real temperature of the lubricating grease of the steering unit at the current moment.

[0086] In an optional implementation, whether the first temperature and the second temperature are valid values ​​can be determined by the working state of the temperature sensor. For example, when the temperature sensor collecting the first temperature fails, it can be determined that the first temperature is not a valid value; when the temperature sensor collecting the second temperature is in a normal working state without failure, it can be determined that the second temperature is a valid value.

[0087] When one of the first temperature and the second temperature is an invalid value, it indicates that the first temperature and the second temperature cannot represent the actual temperature of the lubricating grease. At this time, even if compensation is performed based on the first temperature and the second temperature, the simulation unit cannot finally output a torque to the steering wheel that matches the actual road feel. Therefore, step S102 should be performed when both the first temperature and the second temperature are valid values.

[0088] Before executing step S102, this embodiment first determines whether the torque output by the simulation unit after compensation matches the actual road feel by checking whether the first temperature and the second temperature are both valid values. Then, step S102 is executed to perform compensation only when they match, thereby reducing the number of unnecessary compensation times and improving the working efficiency of the wire-controlled steering system.

[0089] Optionally, the method further comprises: When the first temperature and / or the second temperature is an invalid value, the process proceeds to step S106.

[0090] Step S106, controlling the torque output by the simulation unit based on the state parameter of the steering wheel at the current moment and the driving speed of the vehicle at the current moment; The state parameters include steering wheel speed, steering wheel torque and steering wheel angle.

[0091] An invalid value refers to a value that cannot reflect the true value. The first temperature being an invalid value means that the first temperature obtained cannot reflect the true temperature of the lubricating grease of the simulation unit at the current moment, and the second temperature being an invalid value means that the second temperature obtained cannot reflect the true temperature of the lubricating grease of the steering unit at the current moment.

[0092] When the first temperature, the second temperature, or both the first temperature and the second temperature are invalid values, it indicates that the first temperature and the second temperature cannot represent the real temperature of the lubricating grease. In this case, even if compensation is performed based on the first temperature and the second temperature, the simulation unit cannot output a torque to the steering wheel that matches the real road feel. Therefore, it is necessary to control the torque output by the simulation unit based on the state parameters of the steering wheel at the current moment and the vehicle's driving speed at the current moment.

[0093] In an optional embodiment, step S106 can be implemented in the following manner. Specifically, first, according to the steering wheel torque and steering wheel speed at the current moment, a third compensation torque is calculated by looking up a table. Then, according to the current driving speed, a third compensation coefficient is calculated by looking up a table, and according to the current steering wheel angle, a fourth compensation coefficient is calculated by looking up a table. Finally, the third compensation torque is corrected by the third compensation coefficient and the fourth compensation coefficient to obtain a corrected second compensation torque, and based on the corrected third compensation torque, the torque output by the simulation unit is controlled. Specifically, the compensated third compensation torque can be calculated based on the following formula (3):

[0094] Among them, N 补 is the third compensation torque after compensation, N is the third compensation torque, C5 is the third compensation coefficient, and C6 is the fourth compensation coefficient.

[0095] In this embodiment, when the first temperature, the second temperature, or the first temperature and the second temperature are invalid values, the torque output by the simulation unit is controlled by the state parameters of the steering wheel at the current moment and the vehicle's driving speed at the current moment, so that the linear steering system can complete compensation even when the first temperature and the second temperature fail, thereby improving the stability of the linear steering system.

[0096] Based on the above embodiments, reference Figure 6 A flowchart of a compensation method for a wire-controlled steering system is shown. The following is an exemplary description of the compensation method for the wire-controlled steering system described in the present application: The compensation method of the wire control steering system described in the present application is applied to a linear steering system, and specifically to a controller of the linear steering system. The linear steering system includes a simulation unit and a steering unit. The steering unit is configured to drive the wheel to deflect, and includes a second component, and the distance between the second component and the lubricating grease in the steering unit is less than a second preset distance. The simulation unit is configured to output torque to the steering wheel to simulate road feel, and includes a first component, and the distance between the first component and the lubricating grease in the simulation unit is less than a first preset distance.

[0097] The method described in this application specifically includes the following steps: At the beginning of the method, the temperatures of the first component and the second component at the current moment are respectively obtained, and the first temperature is determined based on the temperature of the first component at the current moment, and the second temperature is determined based on the temperature of the second component at the current moment.

[0098] After obtaining the first temperature and the second temperature, it is first determined whether the first temperature and the second temperature are both valid values.

[0099] If the first temperature and the second temperature are both valid values, a target unit to be compensated is determined based on the first temperature and the second temperature, wherein the target unit includes at least one of a simulation unit and a steering unit, and the temperature of the lubricating grease in the target unit is lower than a temperature threshold at the current moment.

[0100] In the case where the target unit includes a steering unit, the actual rack force of the steering rack at the current moment is first obtained, and then the first compensation coefficient is determined based on the second temperature. Thereafter, the actual rack force is compensated based on the first compensation coefficient to obtain the basic compensation force of the simulation unit. After the basic compensation force is obtained, the torque output by the simulation unit is controlled based on the basic compensation force.

[0101] In the case where the target unit includes a steering unit and a simulation unit, the actual rack force of the steering rack at the current moment is first obtained, and then the second compensation coefficient is determined based on the first temperature, and the first compensation coefficient is determined based on the second temperature. After that, the actual rack force is compensated based on the first compensation coefficient to obtain the basic compensation force of the simulation unit, and the basic compensation force is compensated based on the second compensation coefficient. After the basic compensation force is compensated, the torque output by the simulation unit is controlled based on the compensated basic compensation force.

[0102] At a preset time after the current time, when the target unit includes a steering unit, or includes a steering unit and a simulation unit, the first compensation coefficient can be obtained by the following steps. Specifically, the cumulative stroke of the steering rack is first obtained, where the cumulative stroke is the sum of the movement strokes of the steering rack between the current time and the preset time. Then, based on the second temperature, the first sub-coefficient is determined, and based on the cumulative stroke, the second sub-coefficient is determined. Finally, based on the first sub-coefficient and the second sub-coefficient, the first compensation coefficient is determined.

[0103] If one or both of the first temperature and the second temperature are invalid values, the torque output by the simulation unit is controlled based on the state parameters of the steering wheel at the current moment and the vehicle's driving speed at the current moment; wherein the state parameters include steering wheel speed, steering wheel torque and steering wheel angle.

[0104] Based on the same inventive concept, the present application also provides a compensation system for a wire-controlled steering system, such as Figure 7 As shown in the structural schematic diagram of a compensation system of a wire-controlled steering system, the wire-controlled steering system includes a simulation unit and a steering unit, the steering unit is configured to drive the wheel to deflect, the simulation unit is configured to output torque to the steering wheel to simulate road feel, and the compensation system includes: an acquisition unit, used to respectively acquire a first temperature of the lubricating grease of the simulation unit at a current moment, and a second temperature of the lubricating grease of the steering unit at the current moment; a determining unit, configured to determine a target unit to be compensated based on the first temperature and the second temperature, wherein the target unit includes at least one of the simulation unit and the steering unit, and the temperature of the lubricating grease in the target unit at the current moment is lower than a temperature threshold; A compensation unit, configured to compensate a target force of the target unit based on a temperature of lubricating grease of the target unit at the current moment; The execution unit is used to control the torque output by the simulation unit based on the compensated target force.

[0105] Optionally, the steering unit includes a steering rack. When the target unit includes the steering unit, the compensation unit is used to obtain the actual rack force applied to the steering rack at the current moment; determine a first compensation coefficient based on the second temperature; and compensate for the actual rack force based on the first compensation coefficient to obtain a basic compensation force of the simulation unit.

[0106] The execution unit is used to control the torque output by the simulation unit based on the basic compensation force.

[0107] Optionally, the steering unit includes a steering rack, and when the target unit includes the simulation unit and the steering unit, the compensation unit is used to obtain the actual rack force applied to the steering rack at the current moment; determine the second compensation coefficient based on the first temperature, and determine the first compensation coefficient based on the second temperature; compensate the actual rack force based on the first compensation coefficient to obtain the basic compensation force of the simulation unit; and compensate the basic compensation force based on the second compensation coefficient.

[0108] The execution unit is used to control the torque output by the simulation unit based on the compensated basic compensation force.

[0109] Optionally, at a preset moment after the current moment, the compensation unit is used to obtain the cumulative stroke of the steering rack, the cumulative stroke being the sum of the moving strokes of the steering rack between the current moment and the preset moment; based on the second temperature, determining the first sub-coefficient, and based on the cumulative stroke, determining the second sub-coefficient; based on the first sub-coefficient and the second sub-coefficient, determining the first compensation coefficient.

[0110] Optionally, the simulation unit includes a first component, and the distance between the lubricating grease of the simulation unit and the first component is less than a first preset distance; the steering unit includes a second component, and the distance between the lubricating grease of the steering unit and the second component is less than a second preset distance; the acquisition unit is also used to respectively acquire the temperatures of the first component and the second component at the current moment; determine the first temperature based on the temperature of the first component at the current moment, and determine the second temperature based on the temperature of the second component at the current moment.

[0111] Optionally, the determination unit is also used to determine whether the first temperature and the second temperature are both valid values ​​before determining the target unit to be compensated based on the first temperature and the second temperature; when the first temperature and the second temperature are both valid values, determine the target unit to be compensated based on the first temperature and the second temperature.

[0112] Optionally, the determination unit is also used to control the torque output by the simulation unit based on the state parameters of the steering wheel at the current moment and the driving speed of the vehicle at the current moment when the first temperature and / or the second temperature are invalid values; wherein the state parameters include steering wheel speed, steering wheel torque and steering wheel angle.

[0113] The embodiment of the present application also provides a computer-readable storage medium on which a computer program / instruction is stored. When the computer program / instruction is executed by a processor, a compensation method for a wire-controlled steering system as disclosed in the embodiment of the present application is implemented.

[0114] An embodiment of the present application also provides a vehicle, including a compensation system for a steer-by-wire system provided in the present application, or including a control module, wherein the control module is used to implement the steps of the compensation method for the steer-by-wire system described in the embodiment of the present application.

[0115] The present application provides a compensation method, system, storage medium and vehicle for a wire-controlled steering system, the method comprising: respectively obtaining a first temperature of the lubricant of the simulation unit at a current moment, and a second temperature of the lubricant of the steering unit at the current moment; determining a target unit to be compensated based on the first temperature and the second temperature, the target unit comprising at least one of the simulation unit and the steering unit, and the temperature of the lubricant in the target unit at the current moment is lower than a temperature threshold; compensating for a target force of the target unit based on the temperature of the lubricant of the target unit at the current moment; and controlling the torque output by the simulation unit based on the compensated target force.

[0116] The present application first obtains the temperature of the lubricating grease of the simulation unit and the steering unit at the current moment, and determines at least one of the simulation unit and the steering unit whose lubricating grease temperature at the current moment is lower than the temperature threshold as the target unit, and then compensates the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment. Finally, based on the compensated target force, the torque output by the simulation unit is controlled. The present application determines the target unit that needs to be compensated for the target force by the temperature of the lubricating grease, and compensates the target force according to the temperature of the lubricating grease. Afterwards, the torque output by the simulation unit is controlled according to the compensated target force, thereby eliminating the additional road feel simulation torque due to the increase in the viscosity of the lubricating grease of the wire-controlled steering system through force compensation, thereby improving the authenticity of the road feel simulated by the simulation unit in a low temperature environment.

[0117] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0118] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, systems, electronic devices, and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0119] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0120] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0121] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0122] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0123] The compensation method, system, storage medium and vehicle of a wire-controlled steering system provided by the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A compensation method for a steer-by-wire system, characterized in that: The steer-by-wire system includes a simulation unit and a steering unit, wherein the steering unit is configured to drive the wheel to deflect, and the simulation unit is configured to output torque to the steering wheel to simulate road feel. The method includes: respectively obtaining a first temperature of the lubricating grease of the simulation unit at the current moment and a second temperature of the lubricating grease of the steering unit at the current moment; Based on the first temperature and the second temperature, determining a target unit to be compensated, the target unit comprising at least one of the simulation unit and the steering unit, and the temperature of lubricating grease in the target unit at the current moment is lower than a temperature threshold; Compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment; Based on the compensated target force, the torque output by the simulation unit is controlled.

2. The compensation method of the steer-by-wire system according to claim 1, characterized in that: The steering unit includes a steering rack. When the target unit includes the steering unit, compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment includes: Obtaining an actual rack force applied to the steering rack at the current moment; determining a first compensation coefficient based on the second temperature; Based on the first compensation coefficient, the actual rack force is compensated to obtain a basic compensation force of the simulation unit; The step of controlling the torque output by the simulation unit based on the compensated target force includes: Based on the basic compensation force, the torque output by the simulation unit is controlled.

3. The compensation method of the steer-by-wire system according to claim 1, characterized in that: The steering unit includes a steering rack, and when the target unit includes the simulation unit and the steering unit, compensating the target force of the target unit based on the temperature of the lubricating grease of the target unit at the current moment includes: Obtaining an actual rack force applied to the steering rack at the current moment; determining a second compensation coefficient based on the first temperature, and determining a first compensation coefficient based on the second temperature; Based on the first compensation coefficient, the actual rack force is compensated to obtain a basic compensation force of the simulation unit; Based on the second compensation coefficient, compensating the basic compensation force; The step of controlling the torque output by the simulation unit based on the compensated target force includes: Based on the compensated basic compensation force, the torque output by the simulation unit is controlled.

4. The compensation method of the steer-by-wire system according to claim 2 or 3, characterized in that: At a preset time after the current time, determining a first compensation coefficient based on the second temperature includes: Acquire the accumulated travel of the steering rack, where the accumulated travel is the sum of the movement travel of the steering rack between the current moment and the preset moment; determining a first sub-coefficient based on the second temperature, and determining a second sub-coefficient based on the accumulated travel distance; The first compensation coefficient is determined based on the first sub-coefficient and the second sub-coefficient.

5. The compensation method of the steer-by-wire system according to claim 1, characterized in that: The simulation unit includes a first component, and the distance between the lubricating grease of the simulation unit and the first component is less than a first preset distance. The steering unit includes a second component, and the distance between the lubricating grease of the steering unit and the second component is less than a second preset distance. The first temperature of the lubricating grease of the simulation unit at the current moment and the second temperature of the lubricating grease of the steering unit at the current moment are respectively obtained, including: respectively acquiring the temperature of the first component and the second component at the current moment; The first temperature is determined based on the temperature of the first component at the current moment, and the second temperature is determined based on the temperature of the second component at the current moment.

6. The compensation method of the steer-by-wire system according to claim 1, characterized in that: Before determining the target unit to be compensated based on the first temperature and the second temperature, the method further includes: Determining whether the first temperature and the second temperature are both valid values; The determining a target unit to be compensated based on the first temperature and the second temperature includes: In a case where both the first temperature and the second temperature are valid values, a target unit to be compensated is determined based on the first temperature and the second temperature.

7. The compensation method of the steer-by-wire system according to claim 6, characterized in that: The method further comprises: When the first temperature and / or the second temperature is an invalid value, controlling the torque output by the simulation unit based on the state parameter of the steering wheel at the current moment and the driving speed of the vehicle at the current moment; Wherein, the state parameters include steering wheel speed, steering wheel torque and steering wheel angle.

8. A compensation system for a steer-by-wire system, characterized in that: The steer-by-wire system includes a simulation unit and a steering unit, wherein the steering unit is configured to drive the wheel to deflect, and the simulation unit is configured to output torque to the steering wheel to simulate road feel, and the compensation system includes: an acquisition unit, used to respectively acquire a first temperature of the lubricating grease of the simulation unit at a current moment, and a second temperature of the lubricating grease of the steering unit at the current moment; a determining unit, configured to determine a target unit to be compensated based on the first temperature and the second temperature, wherein the target unit includes at least one of the simulation unit and the steering unit, and the temperature of the lubricating grease in the target unit at the current moment is lower than a temperature threshold; A compensation unit, configured to compensate a target force of the target unit based on a temperature of lubricating grease of the target unit at the current moment; The execution unit is used to control the torque output by the simulation unit based on the compensated target force.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the compensation method for a steer-by-wire system according to any one of claims 1 to 7 are implemented.

10. A vehicle, characterized in that: The invention comprises a compensation system for a steer-by-wire system as claimed in claim 8, or comprises a control module, wherein the control module is used to implement the steps of the compensation method for a steer-by-wire system as claimed in any one of claims 1-7.

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