Vehicle steering control method and device

Abstract

The invention provides a vehicle steering control method and device which can be applied to a controller in a vehicle steering system.The method comprises the steps that under the condition that it is detected that the vehicle steering system is in an end protection mode, a mapping file corresponding to the load state of steering wheels of a vehicle is obtained; the steering wheel load state is one of a grounding state and an off-ground state; the mapping file is inquired according to current steering state information of the vehicle, motor power-assisted parameters corresponding to the steering state information are obtained, and the steering state information comprises at least one of the vehicle speed, the rotating speed of a steering power-assisted motor and the rotating angle of a steering wheel; according to the method provided by the embodiment of the invention, the mapping file corresponding to the load state of the steering wheel can be inquired to obtain the accurate motor power-assisted parameter, so that the steering power-assisted motor can be controlled to output the proper torque, and the vehicle power-assisted steering control method is suitable for the vehicle power-assisted steering system. And the situation that parts collide in the steering process of the vehicle can be effectively avoided.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a vehicle steering control method and device. Background Art

[0002] When the driver controls the vehicle to turn, the power-assisted motor output torque is often needed to assist the steering, so as to help the driver overcome the steering resistance and complete the steering action. The vehicle wheels have maximum steering angles to the left and right. If the driver's wheels exceed the maximum steering angle and continue to apply force on the steering wheel in the direction of the limit, it will cause the components in the steering system to collide.

[0003] In order to avoid collision of components, existing vehicles will be equipped with an end protection strategy for the steering system. Specifically, it is determined whether the electric power steering system EPS has entered the end protection range based on the rack stroke of the steering gear. After entering the end protection range, the greater the rack stroke, the more the power assist is reduced. When the maximum steering angle is reached, the power assist is reduced to the minimum to achieve end protection of the steering system.

[0004] However, the inventors have discovered through research that in some scenarios of the prior art, for example, when the wheel load is small, although the power assist will decrease as the rack stroke increases, the frictional resistance torque of the wheel will decrease as the wheel load decreases. Therefore, the motor only needs to output a very small torque to overcome this friction torque, which can easily lead to collisions between components in the steering system, causing abnormal noises in the vehicle, damage to mechanical components, etc. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a vehicle steering control method and device, which can avoid the collision of components during the wheel steering process. The specific scheme is as follows:

[0006] According to a first aspect of an embodiment of the present invention, a vehicle steering control method is provided, which is applied to a controller in a vehicle steering system, comprising:

[0007] When it is detected that the vehicle steering system is in the terminal protection mode, a mapping file corresponding to the steering wheel load state of the vehicle is obtained; the steering wheel load state is one of a ground contact state and a ground lift state;

[0008] Querying the mapping file according to the current steering state information of the vehicle to obtain a motor power assist parameter corresponding to the steering state information, wherein the steering state information includes at least one of a vehicle speed, a steering power assist motor speed, and a steering wheel angle;

[0009] The output torque of the steering assist motor in the vehicle steering system is controlled based on the motor assist parameter.

[0010] The above method, optionally, the process of detecting that the vehicle steering system is in the terminal protection mode includes:

[0011] Receiving a vehicle speed signal, a vehicle speed effective signal, a steering wheel angle effective signal, and a steering angle mid-position calibration signal of the vehicle;

[0012] If the vehicle speed value in the vehicle speed signal is not greater than a preset vehicle speed threshold, the vehicle speed validity signal indicates that the vehicle speed is valid, the steering wheel angle validity signal indicates that the steering wheel angle is valid, and the steering angle median calibration signal indicates that the steering angle median has been calibrated, then it is determined that the vehicle steering system is in terminal protection mode.

[0013] In the above method, optionally, the step of obtaining a mapping file corresponding to the steering wheel load state of the vehicle includes:

[0014] Acquiring a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle;

[0015] Determining a steering wheel load state of the vehicle according to a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle;

[0016] Obtain a mapping file corresponding to the steering wheel load state.

[0017] The above method, optionally, determining the steering wheel load state of the vehicle according to the steering wheel speed, the steering wheel torque signal and the motor current signal of the power steering motor of the vehicle includes:

[0018] If the steering wheel speed is less than a preset speed threshold, the steering wheel torque signal is less than a preset torque threshold, and the motor current signal is less than a preset current threshold, it is determined that the steering wheel load state of the vehicle is off the ground;

[0019] If the steering wheel speed is not less than a preset speed threshold, the steering wheel torque signal is not less than a preset torque threshold, or the motor current signal is not less than a preset current threshold, it is determined that the steering wheel load state of the vehicle is a grounded state.

[0020] In the above method, optionally, the step of controlling the output torque of the steering assist motor in the vehicle steering system based on the motor assist parameter includes:

[0021] Generate a motor control instruction according to the motor assist parameter;

[0022] The motor control instruction is output to the power steering motor so that the power steering motor outputs a torque corresponding to the motor power assist parameter.

[0023] According to a second aspect of an embodiment of the present invention, there is provided a vehicle steering control device, which is applied to a controller in a vehicle steering system, and the device comprises:

[0024] an execution unit, configured to obtain a mapping file corresponding to a steering wheel load state of the vehicle when it is detected that the vehicle steering system is in a terminal protection mode; the steering wheel load state is one of a ground contact state and a ground lift state;

[0025] a query unit, configured to query the mapping file according to current steering state information of the vehicle to obtain a motor power assist parameter corresponding to the steering state information, wherein the steering state information includes at least one of a vehicle speed, a steering power assist motor speed, and a steering wheel angle;

[0026] A control unit is used to control the output torque of the steering power motor in the vehicle steering system based on the motor power-assist parameter.

[0027] The above device, optionally, an execution unit, includes:

[0028] A receiving subunit, used for receiving a vehicle speed signal, a vehicle speed effective signal, a steering wheel angle effective signal and a steering angle mid-position calibration signal of the vehicle;

[0029] The first determination subunit is used to determine that the vehicle steering system is in the terminal protection mode if the vehicle speed value in the vehicle speed signal is not greater than a preset vehicle speed threshold, the vehicle speed validity signal indicates that the vehicle speed is valid, the steering wheel angle validity signal indicates that the steering wheel angle is valid, and the steering angle median calibration signal indicates that the steering angle median has been calibrated.

[0030] In the above device, optionally, the execution unit includes:

[0031] A first acquisition subunit is used to acquire a steering wheel speed, a steering wheel torque signal and a motor current signal of a power steering motor of the vehicle;

[0032] a second determination subunit, configured to determine a steering wheel load state of the vehicle according to a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle;

[0033] The second acquisition subunit is used to acquire a mapping file corresponding to the steering wheel load state.

[0034] In the above device, optionally, the second determining subunit includes:

[0035] a first determination module, configured to determine that the steering wheel load state of the vehicle is a ground-lift state if the steering wheel speed is less than a preset speed threshold, the steering wheel torque signal is less than a preset torque threshold, and the motor current signal is less than a preset current threshold;

[0036] The second determination module is used to determine that the steering wheel load state of the vehicle is a grounding state if the steering wheel speed is not less than a preset speed threshold, the steering wheel torque signal is not less than a preset torque threshold, or the motor current signal is not less than a preset current threshold.

[0037] In the above device, optionally, the control unit comprises:

[0038] A generating subunit, used for generating a motor control instruction according to the motor assist parameter;

[0039] The output subunit is used to output the motor control instruction to the steering power motor, so that the steering power motor outputs the torque corresponding to the motor power assistance parameter.

[0040] The vehicle steering control method and device provided by the above-mentioned embodiment of the present invention can be applied to the controller in the vehicle steering system, and can obtain the mapping file corresponding to the steering wheel load state of the vehicle when it is detected that the vehicle steering system is in the terminal protection mode; the steering wheel load state is one of the grounded state and the off-ground state; then, the mapping file is queried according to the current steering state information of the vehicle to obtain the motor assist parameter corresponding to the steering state information, and the steering state information includes at least one of the vehicle speed, the steering assist motor speed and the steering wheel angle; finally, the steering assist motor output torque in the vehicle steering system is controlled based on the motor assist parameter. By applying the method provided by the embodiment of the present invention, the mapping file corresponding to the steering wheel load state can be queried according to the steering state information to obtain accurate motor assist parameters, so that the steering assist motor can be controlled to output appropriate torque, which can effectively avoid the collision of components during the vehicle steering process. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0042] Figure 1 A flow chart of a vehicle steering control method provided by the present invention;

[0043] Figure 2 A flowchart of a process of obtaining a mapping file corresponding to a steering wheel load state of a vehicle provided by the present invention;

[0044] Figure 3 An example diagram of a vehicle torque relationship provided by the present invention;

[0045] Figure 4 A flow chart of a terminal protection process provided by the present invention;

[0046] Figure 5 A flow chart of a process for identifying a steering wheel load state provided by the present invention;

[0047] Figure 6 A flowchart of a process for determining whether the EPS terminal protection function is activated provided by the present invention;

[0048] Figure 7 A flowchart of a process for selecting an EPS terminal protection mode provided by the present invention;

[0049] Figure 8 The present invention is a schematic structural diagram of a vehicle steering control device provided by the present invention. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] In this application, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising 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 device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0052] At present, during the vehicle steering process, in order to avoid collision of components in the vehicle steering system, the EPS will be judged whether it has entered the end protection range based on the rack stroke of the steering gear in the steering system. After entering the end protection range, the greater the rack stroke, the more the power assist is reduced. When the maximum steering angle is reached, the power assist is reduced to the minimum to achieve end protection of the steering system.

[0053] However, the inventors have discovered through research that in some scenarios of the prior art, for example, when the wheel load is small, although the power assist will decrease as the rack stroke increases, the frictional resistance torque of the wheel will decrease as the wheel load decreases. Therefore, the motor only needs to output a very small torque to overcome this friction torque, which can easily lead to a collision between the tie rod ball head in the steering system and components such as the steering gear housing, causing abnormal noises in the vehicle and damage to mechanical components.

[0054] Based on this, the present invention provides a vehicle steering control method, which is applied to a controller in a vehicle steering system. The flow chart of the method is as follows: Figure 1 As shown, including:

[0055] S101: when it is detected that the vehicle steering system is in a terminal protection mode, obtaining a mapping file corresponding to a steering wheel load state of the vehicle; the steering wheel load state is one of a ground contact state and a lift-off state.

[0056] In this embodiment, the load on the steering wheel of the vehicle in the grounded state is greater than the load in the off-ground state.

[0057] Optionally, different steering wheel load states correspond to different mapping files, and the mapping file may include a relationship mapping table or a relationship curve, etc., for recording the corresponding relationship between the steering state information and the motor assist parameters.

[0058] S102: querying the mapping file according to the current steering state information of the vehicle to obtain a motor power assist parameter corresponding to the steering state information, wherein the steering state information includes at least one of a vehicle speed, a steering power assist motor speed, and a steering wheel angle.

[0059] In this embodiment, the steering state information may be obtained via a communication bus of the vehicle, and the communication bus may be a CAN bus.

[0060] Optionally, the mapping file records motor assist parameters corresponding to different steering state information.

[0061] In this embodiment, the motor assist parameter may include a terminal protection assist coefficient, and the terminal protection assist coefficient may characterize the terminal protection assist degree. Optionally, if the terminal protection assist coefficient is 100%, there is no terminal protection.

[0062] S103: Controlling the output torque of the steering assist motor in the vehicle steering system based on the motor assist parameter.

[0063] In this embodiment, the motor assist parameter can be directly sent to the power steering motor, so that the power steering motor outputs the torque corresponding to the motor assist parameter. The torque corresponding to the motor assist parameter can also be determined, and then a motor control instruction is generated according to the torque corresponding to the motor assist parameter, and the motor control instruction is sent to the power steering motor, so that the power steering motor outputs the torque.

[0064] By applying the method provided in the embodiment of the present invention, it is possible to query the mapping file corresponding to the steering wheel load state according to the steering state information to obtain accurate motor assist parameters, thereby controlling the steering assist motor to output appropriate torque, which can effectively avoid component collision during vehicle steering.

[0065] In an embodiment provided by the present invention, based on the above solution, optionally, the process of detecting that the vehicle steering system is in the terminal protection mode includes:

[0066] Receiving a vehicle speed signal, a vehicle speed effective signal, a steering wheel angle effective signal, and a steering angle mid-position calibration signal of the vehicle;

[0067] If the vehicle speed value in the vehicle speed signal is not greater than a preset vehicle speed threshold, the vehicle speed validity signal indicates that the vehicle speed is valid, the steering wheel angle validity signal indicates that the steering wheel angle is valid, and the steering angle median calibration signal indicates that the steering angle median has been calibrated, then it is determined that the vehicle steering system is in terminal protection mode.

[0068] In this embodiment, the vehicle speed signal includes a vehicle speed value. After receiving the vehicle speed value, the vehicle speed value is compared with a preset vehicle speed threshold.

[0069] Optionally, the vehicle speed validity signal may indicate whether the vehicle speed is valid. For example, if the vehicle speed validity signal is 1, it indicates that the vehicle speed is valid, and if the vehicle speed validity signal is 0, it indicates that the vehicle speed is invalid.

[0070] Optionally, the steering wheel angle valid signal indicates whether the steering wheel angle is valid. For example, if the steering wheel angle valid signal is 1, it indicates that the vehicle speed is valid, and if the vehicle speed valid signal is 0, it indicates that the vehicle speed is invalid.

[0071] In this embodiment, the corner median calibration signal indicates whether the corner median has been calibrated. For example, if the corner median calibration signal is 1, it indicates that the corner median has been calibrated; if the corner median calibration signal is 0, it indicates that the corner median has not been calibrated.

[0072] In an embodiment provided by the present invention, based on the above implementation process, optionally, the process of obtaining the mapping file corresponding to the steering wheel load state of the vehicle is as follows: Figure 2 As shown, specifically including:

[0073] S201: Acquire the steering wheel speed, steering wheel torque signal and motor current signal of the power steering motor of the vehicle.

[0074] In this embodiment, the steering wheel angle signal and the steering wheel torque signal can be acquired by a sensor, the steering wheel angle signal can represent the current rotation angle of the steering wheel, and the steering wheel torque signal can represent the magnitude of the torque applied by the driving object to the steering wheel; the sensor can be a torque and angle sensor (Torque and Angle Sensor, TAS).

[0075] S202: Determine a steering wheel load state of the vehicle according to a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle.

[0076] In this embodiment, it can be determined whether the steering wheel of the vehicle is currently in a grounded state or off-ground state according to the steering wheel speed, the steering wheel torque signal and the motor current signal of the steering assist motor of the vehicle; specifically, when the driver turns the steering wheel, the TAS torsion bar generates a steering wheel torque Th, that is, a hand torque, and the controller generates a steering wheel torque T according to the steering wheel torque T h Size, look up the table to output the corresponding motor output torque T M , thereby helping the driver to overcome the steering system friction torque T f According to the following formula, the steering wheel torque T can be obtained h , Motor output torque T M and steering system friction torque T f The relationship between:

[0077]

[0078] The motor output torque and the steering wheel torque are positive feedback, that is, the steering wheel torque T h The larger the motor output torque T M The higher the motor output current, the greater the friction torque T can be overcome. f ; Steering wheel torque T h The smaller the motor output torque T M The smaller the motor output current, the smaller the friction torque T can be overcome. f ;

[0079] According to the above characteristics, we can get: when the wheel is off the ground, the steering system friction torque is small, so the required steering wheel torque is small, the motor output torque is small, and the motor output current is small; when the wheel is grounded, the steering system friction torque is large, so the required steering wheel torque is large, the motor output torque is large, and the motor output current is large;

[0080] Take a certain car model as an example, Figure 3The figure below is an example of the relationship between the hand force, motor assistance and corresponding friction torque of the vehicle model. The transmission ratio of the motor output reduction mechanism of the system is G=20.5. When the wheel is in contact with the ground, the steering friction of the steering system in the middle position of the steering wheel is about 72Nm. According to the EPS assistance table, the motor can output a torque of 3.38Nm at the hand force (steering wheel torque) position of 3Nm. Specifically:

[0081]

[0082] When the wheels are in contact with the ground, the steering friction of the steering system near the end position of the steering wheel is about 130Nm. According to the EPS power table, the motor can output a torque of 6Nm at the hand force of 5.5Nm; specifically:

[0083]

[0084] When the wheel is off the ground, the steering friction of the steering system is about 7Nm. According to the EPS power table, the motor can output a torque of 0.3Nm at a hand force of 0.75Nm.

[0085]

[0086] Based on the above analysis, it is possible to identify whether the wheel is currently in a lift-off state or a grounded state by combining the vehicle's steering wheel speed, steering wheel torque signal, and motor current signal of the power steering motor.

[0087] S203: Obtain a mapping file corresponding to the steering wheel load state.

[0088] Optionally, different steering wheel load states correspond to different mapping files; if the steering wheel load state is a lift-off state, the mapping file corresponding to the lift-off state is obtained; if the steering wheel load state is a grounded state, the mapping file corresponding to the grounded state is obtained.

[0089] In an embodiment provided by the present invention, based on the above implementation process, optionally, determining the steering wheel load state of the vehicle according to the steering wheel speed, the steering wheel torque signal and the motor current signal of the steering power motor of the vehicle includes:

[0090] If the steering wheel speed is less than a preset speed threshold, the steering wheel torque signal is less than a preset torque threshold, and the motor current signal is less than a preset current threshold, it is determined that the steering wheel load state of the vehicle is off the ground;

[0091] If the steering wheel speed is not less than a preset speed threshold, the steering wheel torque signal is not less than a preset torque threshold, or the motor current signal is not less than a preset current threshold, it is determined that the steering wheel load state of the vehicle is a grounded state.

[0092] In this embodiment, the steering wheel speed can be compared with a preset speed threshold, the steering wheel torque signal can be compared with a preset torque threshold, and the motor current signal of the power steering motor can be compared with a preset current threshold; based on the above comparison results, the steering wheel load state of the vehicle can be determined.

[0093] Optionally, the speed threshold, torque threshold and current threshold can be calibrated according to actual test conditions. For example, the speed threshold can be set to 200 deg / s, the torque threshold can be set to 1.8 Nm, and the current threshold can be set to 15 A.

[0094] In an embodiment provided by the present invention, based on the above implementation process, optionally, controlling the output torque of the steering assist motor in the vehicle steering system based on the motor assist parameter includes:

[0095] Generate a motor control instruction according to the motor assist parameter;

[0096] The motor control instruction is output to the power steering motor so that the power steering motor outputs a torque corresponding to the motor power assist parameter.

[0097] In this embodiment, the motor control instruction may be used to instruct the power-assisting motor to output a torque corresponding to the motor power-assisting parameter.

[0098] In some embodiments, Figure 4 As shown, a flow chart of an end protection process is provided, which is as follows:

[0099] Step 1: Identify the steering wheel load status based on hand force, motor current and steering wheel speed.

[0100] In this embodiment, three calibrable quantities can be set: the ground-lift steering wheel speed LiftOff_SteeringWhlSpd, the ground-lift steering wheel hand force LiftOff_HandTorq, and the ground-lift motor current LiftOff_MtrCrnt. As shown in Table 1:

[0101] SN Variable Description Variable Name Default value (can be calibrated) 1 Steering wheel speed off the ground LiftOff _SteeringWhlSpd 200deg / s 2 Steering wheel hand force off the ground LiftOff _HandTorq 1.8Nm 3 Off-ground motor current LiftOff _MtrCrnt 15A

[0102] Table 1

[0103] The default values ​​of the lift-off steering wheel speed, the default values ​​of the lift-off steering wheel hand force, and the default values ​​of the lift-off motor current in Table 1 are only examples, and the default values ​​of the present invention are not limited thereto.

[0104] In this embodiment, if Figure 5 As shown, if the vehicle , and the vehicle's ,and, , the load state of the two steering wheels of the vehicle is determined to be off the ground, the front axle load is at the minimum state, and the wheel off the ground state quantity EPS_Whlload_valid in the EPS is set to 0. In other cases, the load state of the steering wheels of the vehicle is determined to be on the ground, the front axle load is at the maximum state, and the wheel off the ground state quantity EPS_Whlload_valid in the EPS is set to 1.

[0105] Step 2: Determine whether to activate the terminal protection function based on the vehicle status.

[0106] In this embodiment, the EPS controller receives the vehicle speed signal Vehspd and the valid vehicle speed signal Vehspd_valid from the CAN signal, the steering wheel angle valid signal StrgWhlAng_valid from the TAS sensor, and the steering angle mid-position calibration signal WhlAngCal_flg, and determines whether the EPS terminal protection function is activated according to the above signals, such as Figure 6 As shown, the specific implementation is as follows:

[0107] If the vehicle speed is valid Vehspd_valid=1, the vehicle speed value Vehspd≤40kph, the center of the steering angle has been calibrated WhlAngCal_flg=1, and the steering wheel angle valid signal StrgWhlAng_valid=1, then it is determined that the end protection function is activated EndPrt_valid=1; otherwise, the end protection function is turned off EndPrt_valid=0.

[0108] If the end protection function is turned off EndPrt_valid = 0, the end protection function is turned off and there is no end protection.

[0109] Step 3: confirm the terminal protection mode according to the steering wheel load status, vehicle speed, and terminal protection function activation status.

[0110] In this embodiment, the process of determining the terminal protection mode is as follows: Figure 7 As shown: the terminal protection mode is in the activated state EndPrt_valid = 1, that is, the vehicle is in the terminal protection mode, the steering wheel is in the off-ground state EPS_Whlload_valid = 0, and the vehicle speed value Vehspd ≤ 1kph, then the vehicle's current terminal protection mode is the off-ground protection mode EPS_EndPrt_Mode = 0;

[0111] The terminal protection mode is in the activated state EndPrt_valid=1, that is, the vehicle is in the terminal protection mode, the steering wheel is in the grounding state EPS_Whlload_valid=1 or the vehicle speed value Vehspd≥1kph, then the current terminal protection mode of the vehicle is the grounding protection mode EPS_EndPrt_mode=1;

[0112] The terminal protection mode is in the off state EndPrt_valid=0, then the vehicle is in the terminal protection exit mode EPS_EndPrt_mode=2;

[0113] Step 4, select a table lookup according to the terminal protection mode, and output the motor assist parameter, which can be the terminal protection gain coefficient.

[0114] In this embodiment, the controller selects the corresponding terminal protection lookup curve according to the terminal protection mode type, and then queries the corresponding terminal protection coefficient according to the vehicle speed, motor speed, and steering wheel angle. Specifically:

[0115] If the steering wheel load state is off-ground, query the two-dimensional table of terminal protection in the off-ground state, and obtain the terminal protection gain coefficient EPS_EndPrt_Gain under different steering wheel speeds and different turning angle positions according to the table lookup.

[0116] If the steering wheel is in the grounded state, query the two-dimensional table of terminal protection in the grounded state, and obtain the terminal protection gain coefficient EPS_EndPrt_Gain under different vehicle speeds, different rotation speeds, and different turning angle positions according to the table lookup.

[0117] and Figure 1 Corresponding to the method described above, the embodiment of the present invention further provides a steering wheel control device for controlling Figure 1 The specific implementation of the method in the steering wheel control device is applied to a controller in a vehicle steering system. The structural schematic diagram of the steering wheel control device is shown in FIG. Figure 8 As shown, specifically including:

[0118] The execution unit 801 is used to obtain a mapping file corresponding to a steering wheel load state of the vehicle when it is detected that the vehicle steering system is in a terminal protection mode; the steering wheel load state is one of a ground contact state and a ground lift state;

[0119] A query unit 802 is used to query the mapping file according to the current steering state information of the vehicle to obtain a motor power assist parameter corresponding to the steering state information, wherein the steering state information includes at least one of a vehicle speed, a steering power assist motor speed, and a steering wheel angle;

[0120] The control unit 803 is used to control the output torque of the steering power motor in the vehicle steering system based on the motor power-assistance parameter.

[0121] In an embodiment provided by the present invention, based on the above solution, optionally, the execution unit includes:

[0122] A receiving subunit, used for receiving a vehicle speed signal, a vehicle speed effective signal, a steering wheel angle effective signal and a steering angle mid-position calibration signal of the vehicle;

[0123] The first determination subunit is used to determine that the vehicle steering system is in the terminal protection mode if the vehicle speed value in the vehicle speed signal is not greater than a preset vehicle speed threshold, the vehicle speed validity signal indicates that the vehicle speed is valid, the steering wheel angle validity signal indicates that the steering wheel angle is valid, and the steering angle median calibration signal indicates that the steering angle median has been calibrated.

[0124] In an embodiment provided by the present invention, based on the above solution, optionally, the execution unit includes:

[0125] A first acquisition subunit is used to acquire a steering wheel speed, a steering wheel torque signal and a motor current signal of a power steering motor of the vehicle;

[0126] a second determination subunit, configured to determine a steering wheel load state of the vehicle according to a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle;

[0127] The second acquisition subunit is used to acquire a mapping file corresponding to the steering wheel load state.

[0128] In an embodiment provided by the present invention, based on the above solution, optionally, the second determining subunit includes:

[0129] a first determination module, configured to determine that the steering wheel load state of the vehicle is a ground-lift state if the steering wheel speed is less than a preset speed threshold, the steering wheel torque signal is less than a preset torque threshold, and the motor current signal is less than a preset current threshold;

[0130] The second determination module is used to determine that the steering wheel load state of the vehicle is a grounding state if the steering wheel speed is not less than a preset speed threshold, the steering wheel torque signal is not less than a preset torque threshold, or the motor current signal is not less than a preset current threshold.

[0131] In an embodiment provided by the present invention, based on the above solution, optionally, the control unit includes:

[0132] A generating subunit, used for generating a motor control instruction according to the motor assist parameter;

[0133] The output subunit is used to output the motor control instruction to the steering power motor, so that the steering power motor outputs the torque corresponding to the motor power assistance parameter.

[0134] It should be noted that 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.

[0135] 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 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 device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0136] For the convenience of description, the above device is described as being divided into various units according to their functions. Of course, when implementing the present invention, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0137] It can be known from the above description of the implementation mode that those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present invention can be essentially or partly contributed to the prior art in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present invention or certain parts of the embodiments.

[0138] The above is a detailed introduction to a vehicle steering method provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A vehicle steering control method, characterized in that: A controller applied to a vehicle steering system, the method comprising: When it is detected that the vehicle steering system is in the terminal protection mode, a mapping file corresponding to the steering wheel load state of the vehicle is obtained; the steering wheel load state is one of a ground contact state and a ground lift state; Querying the mapping file according to the current steering state information of the vehicle to obtain a motor power assist parameter corresponding to the steering state information, wherein the steering state information includes at least one of a vehicle speed, a steering power assist motor speed, and a steering wheel angle; The output torque of the steering assist motor in the vehicle steering system is controlled based on the motor assist parameter.

2. The method according to claim 1, characterized in that The process of detecting that the vehicle steering system is in the terminal protection mode comprises: Receiving a vehicle speed signal, a vehicle speed effective signal, a steering wheel angle effective signal, and a steering angle mid-position calibration signal of the vehicle; If the vehicle speed value in the vehicle speed signal is not greater than a preset vehicle speed threshold, the vehicle speed validity signal indicates that the vehicle speed is valid, the steering wheel angle validity signal indicates that the steering wheel angle is valid, and the steering angle median calibration signal indicates that the steering angle median has been calibrated, then it is determined that the vehicle steering system is in terminal protection mode.

3. The method according to claim 1, characterized in that The obtaining of the mapping file corresponding to the steering wheel load state of the vehicle includes: Acquiring a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle; Determining a steering wheel load state of the vehicle according to a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle; Obtain a mapping file corresponding to the steering wheel load state.

4. The method according to claim 3, characterized in that Determining the steering wheel load state of the vehicle according to the steering wheel speed, the steering wheel torque signal and the motor current signal of the power steering motor of the vehicle includes: If the steering wheel speed is less than a preset speed threshold, the steering wheel torque signal is less than a preset torque threshold, and the motor current signal is less than a preset current threshold, it is determined that the steering wheel load state of the vehicle is off the ground; If the steering wheel speed is not less than a preset speed threshold, the steering wheel torque signal is not less than a preset torque threshold, or the motor current signal is not less than a preset current threshold, it is determined that the steering wheel load state of the vehicle is a grounded state.

5. The method according to claim 1, characterized in that The method of controlling the output torque of the steering assist motor in the vehicle steering system based on the motor assist parameter includes: Generate a motor control instruction according to the motor assist parameter; The motor control instruction is output to the power steering motor so that the power steering motor outputs a torque corresponding to the motor power assist parameter.

6. A vehicle steering control device, characterized in that: A controller used in a vehicle steering system, the device comprising: an execution unit, configured to obtain a mapping file corresponding to a steering wheel load state of the vehicle when it is detected that the vehicle steering system is in a terminal protection mode; the steering wheel load state is one of a ground contact state and a ground lift state; a query unit, configured to query the mapping file according to current steering state information of the vehicle to obtain a motor power assist parameter corresponding to the steering state information, wherein the steering state information includes at least one of a vehicle speed, a steering power assist motor speed, and a steering wheel angle; A control unit is used to control the output torque of the steering power motor in the vehicle steering system based on the motor power-assist parameter.

7. The device according to claim 6, characterized in that Execution unit, including: A receiving subunit, used for receiving a vehicle speed signal, a vehicle speed effective signal, a steering wheel angle effective signal and a steering angle mid-position calibration signal of the vehicle; The first determination subunit is used to determine that the vehicle steering system is in the terminal protection mode if the vehicle speed value in the vehicle speed signal is not greater than a preset vehicle speed threshold, the vehicle speed validity signal indicates that the vehicle speed is valid, the steering wheel angle validity signal indicates that the steering wheel angle is valid, and the steering angle median calibration signal indicates that the steering angle median has been calibrated.

8. The device according to claim 6, characterized in that The execution unit comprises: A first acquisition subunit is used to acquire a steering wheel speed, a steering wheel torque signal and a motor current signal of a power steering motor of the vehicle; a second determination subunit, configured to determine a steering wheel load state of the vehicle according to a steering wheel speed, a steering wheel torque signal, and a motor current signal of a power steering motor of the vehicle; The second acquisition subunit is used to acquire a mapping file corresponding to the steering wheel load state.

9. The device according to claim 8, characterized in that The second determining subunit includes: a first determination module, configured to determine that the steering wheel load state of the vehicle is a ground-lift state if the steering wheel speed is less than a preset speed threshold, the steering wheel torque signal is less than a preset torque threshold, and the motor current signal is less than a preset current threshold; The second determination module is used to determine that the steering wheel load state of the vehicle is a grounding state if the steering wheel speed is not less than a preset speed threshold, the steering wheel torque signal is not less than a preset torque threshold, or the motor current signal is not less than a preset current threshold.

10. The device according to claim 6, characterized in that The control unit comprises: A generating subunit, used for generating a motor control instruction according to the motor assist parameter; The output subunit is used to output the motor control instruction to the steering power motor, so that the steering power motor outputs the torque corresponding to the motor power assistance parameter.

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