Steering Mode Conversion Method and System

Abstract

The present invention provides a steering mode conversion method and system. The method includes: receiving a steering mode conversion instruction, and determining the current steering mode and the target steering mode; respectively obtaining the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode; calculating the commanded steering control parameter at each moment during the transition period based on the first steering control parameter and the second steering control parameter; and generating a steering control instruction according to the commanded steering control parameter. By adding a ramp transition strategy during the steering mode conversion, the present invention reduces the noise and vibration of the electric power steering motor and improves the steering feeling.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and particularly relates to a steering mode conversion method and system. Background Art

[0002] Nowadays, more and more vehicles are equipped with more than one driving mode. The most typical is to configure two driving modes, including a normal mode and a sport mode, or to configure three driving modes, including a comfort mode, a normal mode and a sport mode. Different driving modes also correspond to different steering modes. When the driving mode is switched, the corresponding steering mode also changes. In the existing vehicle system, the driving mode conversion can be achieved through a Driving Mode Control (DMC) button. After the driver presses the driving mode button, the conversion between different driving modes occurs immediately.

[0003] However, for an electric power steering system, when the steering mode is converted, there are sometimes very large differences in the assist torque values between different driving modes, and the assist torque command will change suddenly during the transition time. This will not only cause noise and vibration of some electric power steering motors, but also affect the driver's steering feeling. Summary of the Invention

[0004] Aiming at the problems in the prior art, the purpose of the present invention is to provide a steering mode conversion method and system, which can reduce the noise and vibration of the electric power steering motor and improve the steering feeling by adding a ramp transition strategy during the steering mode conversion.

[0005] An embodiment of the present invention provides a steering mode conversion method, including the following steps:

[0006] Receiving a steering mode conversion instruction, and determining the current steering mode and the target steering mode;

[0007] Respectively obtaining the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode;

[0008] Calculating the command steering control parameter at each moment during the transition period based on the first steering control parameter and the second steering control parameter, and during the transition period, the command steering control parameter gradually changes from the first steering control parameter to the second steering control parameter;

[0009] Generating a steering control instruction according to the command steering control parameter.

[0010] In some embodiments, the step of respectively obtaining the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode includes the following steps:

[0011] Obtain the current steering input information;

[0012] Obtain the first steering control parameter query table for the current steering mode, and query the corresponding first steering control parameter based on the current steering input information;

[0013] Obtain the second steering control parameter query table for the target steering mode, and query the corresponding second steering control parameter based on the current steering input information.

[0014] In some embodiments, the separately obtaining the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode includes the following steps:

[0015] Obtain the current steering assist mode and the current steering input information;

[0016] Obtain the first steering control parameter query table for the current steering mode, and query the corresponding first steering control parameter based on the current steering assist mode and the current steering input information;

[0017] Obtain the second steering control parameter query table for the target steering mode, and query the corresponding second steering control parameter based on the current steering assist mode and the current steering input information.

[0018] In some embodiments, the steering assist mode includes one or more of auxiliary assist, return to center, damping, high-frequency assist, and hysteresis compensation.

[0019] In some embodiments, the steering input information includes one or more of steering wheel torque, steering wheel angle, steering wheel speed, and vehicle speed;

[0020] The steering control parameter is the output torque of the electric power steering motor; after generating the steering control command, it further includes sending the steering control command to the electric power steering motor.

[0021] In some embodiments, the calculating the command steering control parameters at each moment in the transition period based on the first steering control parameter and the second steering control parameter includes the following steps:

[0022] According to the correspondence between the calibratable slope parameter and the moment, obtain the slope parameter at the current moment;

[0023] Based on the slope parameter at the current moment, calculate the command steering control parameters at each moment in the transition period based on the first steering control parameter and the second steering control parameter.

[0024] In some embodiments, in the correspondence between the calibratable slope parameter and the moment, within the transition period, the slope parameter changes from 1 to 0 gradually with the change of the moment;

[0025] The command steering control parameters at each moment during the transition period are calculated using the following formula:

[0026] Command steering control parameter = First steering control parameter * Slope parameter + Second steering control parameter * (1 - Slope parameter).

[0027] In some embodiments, the steering mode conversion instruction includes an instruction for converting between a normal driving mode and an intelligent driving mode, or an instruction for converting between multiple intelligent driving modes.

[0028] An embodiment of the present invention further provides a steering mode conversion system applied to the steering mode conversion method. The system includes:

[0029] A conversion mode determination module, configured to determine the current steering mode and the target steering mode when receiving a steering mode conversion instruction;

[0030] A control parameter acquisition module, configured to respectively acquire the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode;

[0031] A control parameter calculation module, configured to calculate the command steering control parameters at each moment during the transition period based on the first steering control parameter and the second steering control parameter. During the transition period, the command steering control parameter gradually converts from the first steering control parameter to the second steering control parameter;

[0032] A control instruction generation module, configured to generate a steering control instruction according to the command steering control parameter.

[0033] In some embodiments, when the control parameter calculation module calculates the command steering control parameters at each moment during the transition period, it includes: obtaining the slope parameter at the current moment according to the corresponding relationship between the calibratable slope parameter and the moment; based on the slope parameter at the current moment, calculating the command steering control parameters at each moment during the transition period based on the first steering control parameter and the second steering control parameter;

[0034] Wherein, in the corresponding table of the calibratable slope parameter and the moment, at each moment from the start to the end of the transition period, the slope parameter gradually decreases from 1 to 0;

[0035] The control parameter calculation module calculates the command steering control parameters at each moment during the transition period using the following formula:

[0036] Command steering control parameter = First steering control parameter * Slope parameter + Second steering control parameter * (1 - Slope parameter).

[0037] The steering mode conversion method and system provided by the present invention have the following advantages:

[0038] By adopting the present invention, after receiving a steering mode conversion instruction, first determine the current steering mode and the target steering mode, then obtain the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode, calculate the commanded steering control parameter during the transition period, and generate the corresponding steering control instruction. During the transition period, the calculated commanded steering control parameter changes gradually with time. At the beginning of the transition period, the commanded steering control parameter is equal to the first steering control parameter, and at the end of the transition period, the commanded steering control parameter is equal to the second steering control parameter, thereby completing the conversion of the steering mode. At the same time, since the commanded steering control parameter changes gradually, that is, a ramp transition strategy for the steering control parameter is added during the steering mode conversion, the noise and vibration of the electric power steering motor are reduced, and the steering feeling is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Other features, objects, and advantages of the present invention will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings.

[0040] Figure 1 is a flowchart of the steering mode conversion method according to an embodiment of the present invention;

[0041] Figure 2 is a flowchart of obtaining the first steering control parameter and the second steering control parameter according to an embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of the change of the slope parameter with time according to an embodiment of the present invention;)]

[0043] Figure 4 is a graph of the change of the motor torque test under auxiliary power assistance of an existing vehicle system;

[0044] Figure 5 is a graph of the change of the motor torque test under auxiliary power assistance of a vehicle using the method of the present invention;

[0045] Figure 6 is a graph of the change of the steering wheel torque test under auxiliary power assistance of an existing vehicle system;

[0046] Figure 7 is a graph of the change of the steering wheel torque test under auxiliary power assistance of a vehicle using the method of the present invention;

[0047] Figure 8 is a schematic structural diagram of the steering mode conversion system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. Like reference numerals in the figures denote like or similar structures, and thus their repetitive description will be omitted.

[0049] As Figure 1 shown, to solve the problems in the prior art, an embodiment of the present invention provides a steering mode conversion method, including the following steps:

[0050] S100: Receive a steering mode conversion instruction, and determine the current steering mode and the target steering mode;

[0051] Here, receiving the steering mode conversion instruction may be when the driver presses the DMC button to receive the steering mode conversion instruction, or when the driver switches the steering mode through the control panel, etc.; the current steering mode is the steering mode before conversion, and the target steering mode is the steering mode after conversion;

[0052] S200: Obtain the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode, respectively;

[0053] S300: Calculate the command steering control parameter at each moment during the transition period based on the first steering control parameter and the second steering control parameter. During the transition period, the command steering control parameter gradually changes from the first steering control parameter to the second steering control parameter, realizing a gradual transition of the steering control parameter during the transition period, rather than directly converting from the first steering control parameter to the second steering control parameter;

[0054] S400: Generate a steering control instruction according to the command steering control parameter.

[0055] In this embodiment, the steering control parameter is the output torque of the electric power steering motor; in step S400, after generating the steering control instruction, it further includes sending the steering control instruction to the electric power steering motor, that is, the electric power steering motor outputs torque based on the value of the command steering control parameter included in the steering control instruction to realize its electric power steering function.

[0056] By adopting this steering mode conversion method, the present invention first determines the current steering mode and the target steering mode after receiving a steering mode conversion instruction through step S100, then obtains the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode through step S200, calculates the commanded steering control parameter during the transition period through step S300, and generates a corresponding steering control instruction through step S400. In step S300, the calculated commanded steering control parameter changes gradually with time. At the beginning of the transition period, the commanded steering control parameter is equal to the first steering control parameter, and at the end of the transition period, the commanded steering control parameter is equal to the second steering control parameter, thereby completing the conversion of the steering mode. At the same time, since the commanded steering control parameter changes gradually, that is, a ramp transition strategy for increasing the steering control parameter is added during the steering mode conversion, the noise and vibration of the electric power steering motor are reduced, and the steering feeling is improved.

[0057] In this embodiment, in step S100, the steering mode conversion instruction includes an instruction for converting between a normal driving mode and an intelligent driving mode, or an instruction for converting between multiple intelligent driving modes. The intelligent driving mode may include, for example, but is not limited to, a lane keeping mode, an emergency avoidance mode, etc. Therefore, the steering mode conversion of the present invention can be applied to the conversion between a normal driving mode and an intelligent driving mode, or to the conversion between multiple intelligent driving modes.

[0058] In this embodiment, step S200: respectively obtaining the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode includes the following steps:

[0059] Obtain the current steering input information, which may include, for example, but is not limited to, one or more of steering wheel torque, steering wheel angle, steering wheel speed, vehicle speed, etc.;

[0060] Obtain the first steering control parameter query table of the current steering mode, in which the steering control parameters corresponding to different values of the steering input information in the current steering mode are stored;

[0061] Query the corresponding first steering control parameter based on the current steering input information, that is, the steering control parameter that should be adopted currently if still in the current steering mode;

[0062] Obtain the second steering control parameter query table of the target steering mode, in which the steering control parameters corresponding to different values of the steering input information in the target steering mode are stored;

[0063] Query the corresponding second steering control parameter based on the current steering input information, that is, if the conversion to the target steering mode has been completed, the steering control parameter that should be adopted currently.

[0064] In this embodiment, the steering mode conversion method can be applied to various different steering assist modes. The steering assist modes can include, for example, but are not limited to, one or more of assisted steering, return to center, damping, high-frequency assist, and hysteresis compensation. In different steering assist modes, corresponding to different steering input information, there will also be different steering control parameters.

[0065] Therefore, as Figure 2 shown, in one implementation manner of this embodiment, the step S200: respectively obtain the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode, includes the following steps:

[0066] S210: Obtain the current steering assist mode and the current steering input information;

[0067] S220: Obtain the first steering control parameter query table of the current steering mode. The first steering control parameter query table stores the steering control parameters corresponding to different values of various steering assist modes and steering input information in the current steering mode;

[0068] S230: Query the corresponding first steering control parameter based on the current steering assist mode and the current steering input information, that is, if still in the current steering mode, the steering control parameter that should be adopted currently;

[0069] S240: Obtain the second steering control parameter query table of the target steering mode. The second steering control parameter query table stores the steering control parameters corresponding to different values of various steering assist modes and steering input information in the target steering mode;

[0070] S250: Query the corresponding second steering control parameter based on the current steering assist mode and the current steering input information, that is, if the conversion to the target steering mode has been completed currently, the steering control parameter that should be adopted currently.

[0071] In a vehicle control architecture, pre-calibrated steering control parameters for different steering modes are placed in different runtimes. When switching between different steering modes, the conversion of the steering control parameter lookup table is performed through pointers and addresses. It is impossible to directly perform interpolation calculations on the steering control parameter lookup tables of two steering modes. Therefore, through the above step S300, the present invention adds a redundant steering control parameter ramp transition strategy, and calculates the commanded steering control parameters at each moment during the transition period based on the first steering control parameter and the second steering control parameter retrieved from the steering control parameter lookup tables of two steering modes, so as to use them as the commanded steering control parameters at each moment.

[0072] In this embodiment, the step S300: calculating the commanded steering control parameters at each moment during the transition period based on the first steering control parameter and the second steering control parameter includes the following steps:

[0073] According to the correspondence between the calibratable slope parameter and the moment, the slope parameter at the current moment is obtained. The correspondence between the slope parameter and the moment can be a formula for calculating the slope parameter based on the moment variable, or can be stored as a lookup table of the slope parameter and the moment, and the lookup table stores the calibratable slope parameter values corresponding to each moment during the transition period;

[0074] Based on the slope parameter at the current moment, calculate the commanded steering control parameters at each moment during the transition period based on the first steering control parameter and the second steering control parameter.

[0075] Specifically, in the lookup table of the correspondence between the calibratable slope parameter and the moment, during the transition period, the slope parameter gradually decreases from 1 to 0 as the moment changes. As Figure 3 shown, in this embodiment, at the start of the transition period (0 moment), the value of the slope parameter is 1, and at the end of the transition period (t1 moment), the value of the slope parameter is 0, and during the transition period (0 moment to t1 moment), the change of the slope parameter is a linear change. Among them, the transition time is calibratable.

[0076] In this embodiment, the following formula is used to calculate the commanded steering control parameters at each moment during the transition period:

[0077] Commanded steering control parameter = First steering control parameter * Slope parameter + Second steering control parameter * (1 - Slope parameter).

[0078] At the start of the transition period (time 0), the value of the slope parameter is 1, and the commanded steering control parameter = the first steering control parameter. At the end of the transition period (time t1), the commanded steering control parameter = the second steering control parameter. And since the slope parameter is a linearly varying value, the commanded steering control parameter is also a linearly varying value. When the first steering control parameter is greater than the second steering control parameter, the commanded steering control parameter gradually decreases from the first steering control parameter to the second steering control parameter. When the first steering control parameter is less than the second steering control parameter, the commanded control parameter gradually increases from the first steering control parameter to the second steering control parameter.

[0079] As Figure 3 shown, the change of the slope parameter is a linearly decreasing change, and the change rate of the slope parameter depends on the total duration of the transition period. When the change rate of the slope parameter is fast, the commanded steering control parameter will transition from the first steering control parameter to the second steering parameter relatively quickly, but shortening the transition time may cause motor noise and vibration. When the change rate of the slope parameter is slow, the commanded steering control parameter will transition from the first steering control parameter to the second steering parameter relatively slowly, reducing motor noise and vibration, but it will extend the transition time, and it may take a relatively long time to complete the transition. The change rate of the slope parameter can be expressed as 1 / t1, and the value of this change rate can be calibrated in advance through tests to select an appropriate change rate.

[0080] In another embodiment, the change trend of the slope parameter from time 0 to time t1 can also be a curve, that is, not an absolute linear change, as long as it satisfies that the value of the slope parameter gradually decreases from 1 to 0 during the process from time 0 to time t1.

[0081] Furthermore, for different steering assist modes, different change rates of the slope parameter can also be provided. Different corresponding relationships between the slope parameter and time are set for different steering assist modes. For example, the change rate of the slope parameter set under auxiliary assist is different from the change rate of the slope parameter set under return to center. The corresponding relationships between the slope parameter and time corresponding to each steering assist mode are stored in advance. The obtaining of the slope parameter at the current time according to the calibratable corresponding relationship between the slope parameter and time includes: querying the corresponding relationship between the calibratable slope parameter and time in this steering assist mode according to the current steering assist mode to obtain the slope parameter at the current time.

[0082] Further, for different steering mode conversion situations, different slope parameter change speeds can also be provided. For example, the change speed of the slope parameter when switching from the comfort mode to the sport mode is different from that when switching from the normal mode to the sport mode. The mapping relationship among the current steering mode - target steering mode - slope parameter and time is pre-stored. The obtaining of the slope parameter at the current time according to the calibratable correspondence between the slope parameter and time includes: based on the mapping relationship among the current steering mode - target steering mode - slope parameter and time, obtaining the correspondence between the current slope parameter and time, and looking up this correspondence to obtain the slope parameter at the current time.

[0083] Figure 4 and Figure 5 respectively show the motor torque test change curve of the existing vehicle system under auxiliary power assistance and the motor torque test change curve of the vehicle adopting the method of the present invention under auxiliary power assistance. Figure 6 and Figure 7 respectively show the steering wheel torque test change curve of the existing vehicle system under auxiliary power assistance and the steering wheel torque test change curve of the vehicle adopting the method of the present invention under auxiliary power assistance.

[0084] In Figures 4 to 7 , the abscissa represents time respectively, with the unit of second (s). The ordinate above represents the pointer of the steering mode. For example, when the pointer is 2, it corresponds to the comfort mode; when the pointer is 1, it corresponds to the normal mode; when the pointer is 0, it corresponds to the sport mode. The specific correspondence between the pointer and the mode can be adjusted, increased or decreased according to needs. Figure 4 and Figure 5 , the ordinate below represents the required torque of the motor, with the unit of motor output N.m. Figure 6 and Figure 7 , the ordinate below represents the torque of the steering wheel, with the unit of steering wheel hand force N.m.

[0085] As Figure 4 shown, A1 represents the conversion of the steering mode, and A2 represents the change curve of the motor required motor. In the existing vehicle system, when the steering mode changes, there will be a sudden change in the motor required torque, which is likely to generate motor noise and vibration. As Figure 6 shown, C1 represents the conversion of the steering mode, and C2 represents the change curve of the steering wheel torque. In the existing vehicle system, when the steering mode changes, there will also be a sudden change in the hand force of the steering wheel, which also gives a bad experience to the driver. After adopting the steering mode conversion method of the present invention, as Figure 5As shown, B1 represents the conversion of the steering mode, and B2 represents the change curve of the motor demand of the motor. When the steering mode is converted, the change of the motor demand torque is smoother, reducing the motor noise and vibration. As Figure 7 shown, D1 represents the conversion of the steering mode, and D2 represents the change curve of the steering wheel torque. The change of the hand force of the steering wheel is also smoother, improving the driver's experience.

[0086] As Figure 8 shown, an embodiment of the present invention further provides a steering mode conversion system, which is applied to the steering mode conversion method described above. The system includes:

[0087] A conversion mode determination module M100, configured to determine the current steering mode and the target steering mode when receiving a steering mode conversion instruction;

[0088] A control parameter acquisition module M200, configured to respectively acquire a first steering control parameter and a second steering control parameter in the current steering mode and the target steering mode;

[0089] A control parameter calculation module M300, configured to calculate the command steering control parameters at each moment in the transition period based on the first steering control parameter and the second steering control parameter. During the transition period, the command steering control parameter gradually converts from the first steering control parameter to the second steering control parameter;

[0090] A control instruction generation module M400, configured to generate a steering control instruction according to the command steering control parameter.

[0091] In the present invention, by adopting the steering mode conversion system, first, after the conversion mode determination module M100 receives a steering mode conversion instruction, the current steering mode and the target steering mode are determined. Then, the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode are acquired by the control parameter acquisition module M200. The command steering control parameters in the transition period are calculated by the control parameter calculation module M300, and the corresponding steering control instructions are generated by the control instruction generation module M400. Among them, the calculated command steering control parameters change gradually with time. At the beginning of the transition period, the command steering control parameter is equal to the first steering control parameter. At the end of the transition period, the command steering control parameter is equal to the second steering control parameter, thereby completing the conversion of the steering mode. At the same time, since the command steering control parameter changes gradually, that is, a ramp transition strategy for increasing the steering control parameter is added during the steering mode conversion, reducing the noise and vibration of the electric power steering motor and improving the steering feeling.

[0092] In this embodiment, the control parameter calculation module M300 calculates the command steering control parameters at each moment during the transition period, including: obtaining the slope parameter at the current moment according to the corresponding relationship between the calibratable slope parameter and the moment; and calculating the command steering control parameters at each moment during the transition period based on the slope parameter at the current moment, the first steering control parameter, and the second steering control parameter. Among them, in the corresponding table of the calibratable slope parameter and the moment, within the transition period, the slope parameter gradually decreases from 1 to 0 as the moment changes.

[0093] The control parameter calculation module M300 calculates the command steering control parameters at each moment during the transition period by using the following formula:

[0094] Command steering control parameter = First steering control parameter * Slope parameter + Second steering control parameter * (1 - Slope parameter).

[0095] In this embodiment, the control parameter acquisition module M200 can obtain the first steering control parameter and the second steering control parameter by using the Figure 2 process shown.

[0096] The above content is a further detailed description of the present invention in combination with specific preferred embodiments. It cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. A steering mode conversion method, characterized in that: The steps include: Receiving a steering mode conversion instruction, determining a current steering mode and a target steering mode; respectively obtaining a first steering control parameter and a second steering control parameter in a current steering mode and a target steering mode; calculating a command steering control parameter at each moment in a transition period based on the first steering control parameter and the second steering control parameter, wherein during the transition period, the command steering control parameter gradually switches from the first steering control parameter to the second steering control parameter; generating a steering control instruction according to the command steering control parameter; Wherein, a mapping relationship between the current steering mode, the target steering mode, the slope parameter, and the corresponding relationship between the time is pre-stored, and the command steering control parameter at each time in the transition period is calculated based on the first steering control parameter and the second steering control parameter, including the following steps: Based on the mapping relationship between the current steering mode, the target steering mode, and the corresponding relationship between the slope parameter and the time, the corresponding relationship between the current slope parameter and the time is obtained, and the slope parameter at the current time is obtained by searching the corresponding relationship. During the transition period, the slope parameter gradually decreases with the change of time; Based on the slope parameter at the current moment, the command steering control parameter at each moment in the transition period is calculated based on the first steering control parameter and the second steering control parameter, and the slope parameter defines the proportion of the first steering control parameter in the command steering control parameter.

2. The steering mode conversion method according to claim 1, characterized in that: The steps of respectively obtaining the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode include the following steps: Get the current steering input information; Obtaining a first steering control parameter query table for the current steering mode, and obtaining a corresponding first steering control parameter based on the current steering input information; A second steering control parameter query table of the target steering mode is obtained, and a corresponding second steering control parameter is obtained based on the current steering input information.

3. The steering mode conversion method according to claim 1, characterized in that: The steps of respectively obtaining the first steering control parameter and the second steering control parameter in the current steering mode and the target steering mode include the following steps: Get the current steering assist mode and current steering input information; Obtaining a first steering control parameter query table for the current steering mode, and obtaining a corresponding first steering control parameter based on the current steering assist mode and the current steering input information; A second steering control parameter query table of the target steering mode is obtained, and a corresponding second steering control parameter is obtained based on the current steering assist mode and the current steering input information.

4. The steering mode conversion method according to claim 3, characterized in that: The steering assist mode includes one or more of auxiliary assist, return, damping, high-frequency assist and hysteresis compensation.

5. The steering mode conversion method according to claim 2 or 3, characterized in that: The steering input information includes one or more of steering wheel torque, steering wheel angle, steering wheel speed and vehicle speed; The steering control parameter is the output torque of the electric power steering motor; after generating the steering control instruction, the method further includes sending the steering control instruction to the electric power steering motor.

6. The steering mode conversion method according to claim 1, characterized in that: In the correspondence between the slope parameter and the time, during the transition period, the slope parameter gradually decreases from 1 to 0 as the time changes; The command steering control parameters at each moment in the transition period are calculated using the following formula: Command steering control parameter=first steering control parameter*slope parameter+second steering control parameter*(1-slope parameter).

7. The steering mode conversion method according to claim 1, characterized in that: The steering mode conversion instruction includes an instruction for converting between a normal driving mode and an intelligent driving mode, or an instruction for converting between multiple intelligent driving modes.

8. A steering mode conversion system, characterized in that: The steering mode conversion method according to any one of claims 1 to 7, wherein the system comprises: A conversion mode determination module is used to determine the current steering mode and the target steering mode when receiving a steering mode conversion instruction; A control parameter acquisition module, configured to respectively acquire a first steering control parameter and a second steering control parameter in a current steering mode and a target steering mode; a control parameter calculation module, configured to calculate a command steering control parameter at each moment in a transition period based on the first steering control parameter and the second steering control parameter, wherein during the transition period, the command steering control parameter is gradually converted from the first steering control parameter to the second steering control parameter; A control instruction generating module is used to generate a steering control instruction according to the command steering control parameter.

9. The steering mode conversion system according to claim 8, characterized in that: The control parameter calculation module calculates the command steering control parameter at each moment in the transition period, including: obtaining the slope parameter at the current moment based on the corresponding relationship between the calibratable slope parameter and the time; and calculating the command steering control parameter at each moment in the transition period based on the slope parameter at the current moment and the first steering control parameter and the second steering control parameter; Wherein, in the correspondence table between the calibratable slope parameter and the time, the slope parameter gradually decreases from 1 to 0 at each time from the beginning to the end of the transition period; The control parameter calculation module calculates the command steering control parameter at each moment in the transition period using the following formula: Command steering control parameter=first steering control parameter*slope parameter+second steering control parameter*(1-slope parameter).

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