A vehicle steering control method, device, vehicle and readable storage medium

Abstract

This invention provides a vehicle steering control method, device, vehicle, and readable storage medium. The method includes: when the vehicle is in an automated assisted navigation driving state, if it is determined that the vehicle needs to turn, acquiring the vehicle's current speed and a target requested torque; determining an assist torque limit value based on the current speed; wherein the assist torque limit value is an upper limit value of assist torque at the current speed that allows the driver to control the vehicle's steering in the opposite direction to the assist torque; determining an actual assist torque based on the assist torque limit value and the target requested torque; and controlling the vehicle to steer based on the actual assist torque. This invention can effectively balance assisted steering needs and ensure the vehicle remains under control.

Description

Technical Field

[0001] This invention relates to the field of automotive technology, and in particular to a vehicle steering control method, device, vehicle, and readable storage medium. Background Technology

[0002] Currently, with the development of technology, more and more vehicles are equipped with Navigate on Hi Autopilot (NOH), which is a function that deeply integrates the navigation system with Highway Assist (HWA). It can control the vehicle to automatically switch highway lanes according to the navigation and assist the driver in entering and exiting ramps, as well as intelligently adjust the cruise speed on the current road.

[0003] In the prior art, electric power steering (EPS) sets a fixed torque limit value for the assist torque of the automatic assisted navigation driving function to avoid the vehicle deviating from the fixed lane due to excessive or unexpected steering assistance provided by electric power steering, which could lead to the risk of the vehicle hitting obstacles or other vehicles.

[0004] However, the above method of setting a fixed torque limit value for the power assist torque has several drawbacks. If the torque limit value is set too low, the output torque of the EPS may be insufficient, causing the vehicle to be unable to meet the requirements for entering and exiting ramps. If the torque limit value is set too high, the driver may lose control of the vehicle when the vehicle is traveling at high speed and the EPS malfunctions instead of outputting the maximum steering torque as expected. Summary of the Invention

[0005] In view of this, the present invention aims to provide a vehicle steering control method, device, vehicle, and readable storage medium to solve the problem that the steering control method using a fixed torque limit value in the existing automatic assisted navigation driving technology is unreasonable, and to easily and effectively balance effective assisted steering and vehicle controllability.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] A vehicle steering control method, wherein the method includes:

[0008] When the vehicle is in an automatic assisted navigation driving state, if it is determined that the vehicle needs to turn, the current speed of the vehicle and the target requested torque are obtained.

[0009] Based on the current vehicle speed, a power assist torque limit value is determined; wherein, the power assist torque limit value is the upper limit value of the power assist torque that the driver can control the vehicle steering in the opposite direction to the power assist torque at the current vehicle speed;

[0010] The actual assist torque is determined based on the assist torque limit value and the target requested torque;

[0011] The vehicle is steered according to the actual assist torque.

[0012] Furthermore, in the control method, determining the actual assist torque based on the assist torque limit value and the target requested torque includes:

[0013] Determine the target assist torque based on the target requested torque;

[0014] The actual assist torque is determined based on the assist torque limit value and the target assist torque.

[0015] Furthermore, in the control method, the vehicle stores a correspondence between vehicle speed and assist torque limit value;

[0016] Based on the current vehicle speed, determine the target assist torque limit value, including:

[0017] The assist torque limit value is determined based on the current vehicle speed and the corresponding relationship.

[0018] Furthermore, in the control method, determining the actual assist torque based on the target assist torque limit value and the target assist torque includes:

[0019] If the target assist torque is less than or equal to the assist torque limit value, the target assist torque is determined as the actual assist torque;

[0020] If the target assist torque is greater than the target assist torque limit value, the assist torque limit value is determined as the actual assist torque.

[0021] Furthermore, in the control method, after determining the assist torque limit as the actual assist torque when the target assist torque is greater than the assist torque limit, the method further includes:

[0022] It can acquire the active steering torque emitted by the driver through the steering wheel;

[0023] Based on the actual assist torque, control the vehicle to steer, including:

[0024] The vehicle is steered according to the actual assist torque and the active steering torque.

[0025] Another object of the present invention is to provide a vehicle steering control device, wherein the device comprises:

[0026] The first acquisition module is used to acquire the vehicle's current speed and target requested torque when the vehicle is in an automatic assisted navigation driving state and it is determined that the vehicle needs to turn.

[0027] The first determining module is used to determine the assist torque limit value based on the current vehicle speed; wherein, the assist torque limit value is the upper limit value of the assist torque at the current vehicle speed, which allows the driver to control the vehicle steering in the opposite direction to the assist torque.

[0028] The second determining module is used to determine the actual assist torque based on the assist torque limit value and the target requested torque;

[0029] The control module is used to control the vehicle to steer based on the actual assist torque.

[0030] Furthermore, in the control device, the second determining module includes:

[0031] The first determining unit is used to determine the target assist torque based on the target requested torque;

[0032] The second determining unit is used to determine the actual assist torque based on the assist torque limit value and the target assist torque.

[0033] Furthermore, in the control device, the vehicle stores a correspondence between vehicle speed and assist torque limit value;

[0034] The first determining module is specifically used to determine the assist torque limit value based on the current vehicle speed and the corresponding relationship.

[0035] Furthermore, in the control device, the second determining unit includes:

[0036] The first determining subunit is used to determine the target assist torque as the actual assist torque when the target assist torque is less than or equal to the assist torque limit value;

[0037] The second determining subunit is used to determine the assist torque limit value as the actual assist torque when the target assist torque is greater than the assist torque limit value.

[0038] Furthermore, the device also includes:

[0039] The second acquisition module is used to acquire the active steering torque emitted by the driver through the steering wheel after determining the assist torque limit value as the actual assist torque when the target assist torque is greater than the assist torque limit value.

[0040] The control module is specifically used to control the vehicle to steer based on the actual assist torque and the active steering torque.

[0041] Compared with current technology, the vehicle steering control method and device described in this invention have the following advantages:

[0042] When the vehicle is in automatic assisted navigation driving mode, if it is determined that the vehicle needs to turn, the system obtains the vehicle's current speed and the target requested torque. Based on the current speed, it determines the assist torque limit value. This assist torque limit value is the upper limit of the assist torque that the driver can use to control the vehicle's steering in the opposite direction at the current speed. Based on the assist torque limit value and the target requested torque, it determines the actual assist torque. Finally, it controls the vehicle to steer based on the actual assist torque. Because the assist torque limit value is determined based on the vehicle's current speed, which is directly related to the ease with which the driver can control the vehicle's steering, and the actual assist torque is determined by combining the target requested torque required for steering with the aforementioned assist torque limit value, the system can effectively balance the assisted steering needs and ensure that the vehicle remains under control.

[0043] Another object of the present invention is to provide a vehicle, wherein the vehicle includes the aforementioned vehicle steering control device.

[0044] The present invention also proposes a readable storage medium, wherein a program or instructions are stored on the readable storage medium, and when the program or instructions are executed by a processor, the vehicle steering control method as described above is implemented.

[0045] The present invention also provides a chip, the chip including a processor and a communication interface, the communication interface being coupled to the processor, the processor being used to run programs or instructions to implement the vehicle steering control method as described above.

[0046] The vehicle, readable storage medium, and chip described above have the same advantages over the prior art as the vehicle steering control method and device described above, and will not be repeated here. Attached Figure Description

[0047] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0048] Figure 1 This is a schematic diagram of the vehicle steering control method proposed in an embodiment of the present invention;

[0049] Figure 2 This is a schematic diagram illustrating the process of determining the correspondence between the assist torque limit value and vehicle speed in an embodiment of the present invention;

[0050] Figure 3This is a schematic diagram illustrating the change of NOH requested torque over time in an embodiment of the present invention;

[0051] Figure 4 This is a schematic diagram illustrating the correspondence between vehicle speed and assist torque limit values ​​in an embodiment of the present invention;

[0052] Figure 5 This is a schematic diagram of the vehicle steering control strategy provided in an embodiment of the present invention;

[0053] Figure 6 This is a schematic diagram of the vehicle steering control device proposed in an embodiment of the present invention. Detailed Implementation

[0054] Embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0055] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0056] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0057] Please see Figure 1 The diagram shows a schematic flowchart of a vehicle steering control method provided by an embodiment of the present invention, the method including steps S100 to S400.

[0058] The vehicle steering control method provided in this embodiment of the invention is specifically applied to the vehicle controller, which is communicatively connected to the vehicle's electronic power steering system and advanced driver assistance system.

[0059] S100. When the vehicle is in an automatic assisted navigation driving state, if it is determined that the vehicle needs to turn, obtain the vehicle's current speed and target requested torque.

[0060] In step S100 above, the requested torque is the torque sent by the controller of the advanced driver assistance system to the vehicle's electronic power steering system according to the vehicle's steering needs; step S100 above means that when the vehicle is in an automatic assisted navigation driving state and the automatic assisted navigation driving function determines that the vehicle needs to turn, the current vehicle speed is detected by the vehicle speed sensor and the target requested torque sent by the controller of the advanced driver assistance system is received.

[0061] Step S200: Determine the assist torque limit value based on the current vehicle speed; wherein the assist torque limit value is at the current vehicle speed.

[0062] In step S200 above, the assist torque limit value is the upper limit of the assist torque provided by the electronic power steering system within the driver's controllable range at the current vehicle speed. Specifically, it is the upper limit of the assist torque that the driver can control the vehicle to steer in the opposite direction to the assist torque. That is, under the premise that the driver can control the vehicle to overcome the assist torque provided by the electronic power steering system to steer in the opposite direction to the assist torque, the electronic power steering system can provide the maximum assist torque.

[0063] In step S200 above, since the difficulty of the driver controlling the vehicle steering, that is, the torque required for the driver to control the vehicle steering, is directly related to the vehicle speed, the upper limit value of the assist torque at the current vehicle speed can be determined by the current vehicle speed, so as to dynamically adjust the assist torque limit value of the electronic power steering system according to the different vehicle speeds when the vehicle is steering.

[0064] The assist torque limit value varies with vehicle speed; specifically, the lower the vehicle speed, the larger the assist torque limit value, and the higher the vehicle speed, the smaller the assist torque limit value. This avoids the situation where the NOH function performance is insufficient to meet steering requirements due to the limit value being too small when driving at low speeds; it also avoids the situation where the assist torque limit value is too large when driving at high speeds, resulting in excessive assist and the vehicle exceeding the driver's control ability.

[0065] Step S300: Determine the actual assist torque based on the assist torque limit value and the target requested torque.

[0066] In step S300 above, since the assist torque limit value limits the upper limit of the assist torque provided by the electric power steering system within the driver's controllable range at the current vehicle speed, and the target requested torque describes the assist torque required for normal vehicle control, the assist torque actually output by the electronic power steering system can be coordinated from the above assist torque limit value and the above target requested torque to ensure that the driver can effectively control the vehicle steering and to meet the actual steering needs of the vehicle to the maximum extent.

[0067] Step S400: Control the vehicle to steer according to the actual assist torque.

[0068] In step S400 above, since the actual assist torque is the assist torque actually output by the electronic power steering system under the premise that the driver can effectively control the vehicle steering and to the maximum extent to meet the actual steering needs of the vehicle, when the vehicle is steered according to the actual assist torque, there will be no situation where the driver cannot control the vehicle when the vehicle is traveling at high speed and the EPS malfunctions instead of the expected maximum steering torque output, nor will there be a situation where the EPS output torque is too small, causing the vehicle to be unable to meet the requirements for entering and exiting the ramp.

[0069] Compared with existing technologies, the vehicle steering control method of the present invention has the following advantages:

[0070] When the vehicle is in autonomous driving mode, if it is determined that the vehicle needs to turn, the current vehicle speed and the target requested torque are obtained. Based on the current vehicle speed, an assist torque limit value is determined. This assist torque limit value is the upper limit of the assist torque that the driver can use to control the vehicle's steering in the opposite direction at the current vehicle speed. Based on the assist torque limit value and the target requested torque, the actual assist torque is determined. The vehicle is then steered based on the actual assist torque. Because the assist torque limit value is determined based on the current vehicle speed, which is directly related to the ease with which the driver can control the vehicle's steering, and the actual assist torque is determined based on the target requested torque required for steering, combined with the aforementioned assist torque limit value, the assisted steering demand can be effectively balanced while ensuring the vehicle remains controllable. This solves the problem of the unreasonable use of fixed torque limit values ​​in existing autonomous driving technologies, and effectively balances effective assisted steering with vehicle controllability.

[0071] Optionally, in one embodiment, the vehicle stores a correspondence between vehicle speed and assist torque limit values;

[0072] The above step S200 includes step S201:

[0073] Step S201: Determine the assist torque limit value based on the current vehicle speed and the corresponding relationship.

[0074] In this embodiment, a correspondence between vehicle speed and the power steering torque limit is established beforehand through experiments. That is, the upper limit of the power steering torque at any given vehicle speed, which allows the driver to control the vehicle's steering in the opposite direction to the power steering torque, is determined in advance through experiments. Then, in actual application, after obtaining the vehicle's current speed, the power steering torque limit corresponding to the current speed can be quickly determined using the aforementioned correspondence. Using this power steering torque limit as the upper limit of the power steering system's output torque ensures that the vehicle is always in a state where the driver can control the steering.

[0075] In practical applications, please refer to Figure 2 The diagram illustrates the process of determining the correspondence between the assist torque limit value and vehicle speed in an embodiment of the present invention.

[0076] like Figure 2 As shown, in step S211, the vehicle speed and the minimum turning radius at that speed are first determined. At the same vehicle speed, the smaller the turning radius, the greater the assist torque required to achieve the NOH function; that is, the NOH assist torque at this speed is the maximum assist torque at that vehicle speed.

[0077] In step S212, the target assist torque corresponding to the NOH function is set, then the NOH function is turned on, and the vehicle is driven at the speed and turning radius determined in step S211. The vehicle is then driven stably on the prescribed route by adjusting the target assist torque of the NOH function.

[0078] In step S213, the vehicle's NOH function is turned off. The vehicle is driven under the speed and turning radius conditions determined in step S211. When the vehicle is traveling at a constant speed around a specific turning radius, the maximum NOH torque request is suddenly sent to the EPS via relevant equipment. Specifically, as follows... Figure 3 As shown, at this time, the EPS will provide assistance according to the NOH function target assist torque set in step 2.

[0079] In step S214, it is determined whether the driver can control the vehicle steering. This can be done by referring to the driver's subjective evaluation criteria, which are shown in Table 1.

[0080] After sending the maximum NOH requested torque, confirm whether the driver can control the vehicle within the designated lane; if the driver cannot control the vehicle within the lane, return to step S212 to reduce the NOH function target assist torque until the driver can control the vehicle within the designated lane after sending the maximum NOH requested torque.

[0081] In step S215, the target assist torque obtained in step S214 is used as the assist torque limit value corresponding to the vehicle speed determined in step S211.

[0082] Repeat steps S211 to S215 above to determine the corresponding assist torque limit values ​​at different vehicle speeds, thereby obtaining the correspondence between vehicle speed and assist torque limit values, as detailed below. Figure 4 As shown.

[0083] Table 1

[0084]

[0085] In Table 1, the driver's subjective evaluation standard is that a score of ≤2 indicates that the driver can control the vehicle's steering.

[0086] Optionally, in one embodiment, step S300 includes steps S301 to S302:

[0087] Step S301: Determine the target assist torque based on the target requested torque.

[0088] In step S301 above, when the electronic power steering system performs power steering, it amplifies the requested torque issued by the controller of the advanced driver assistance system and uses it as the actual required output torque. That is, there is a proportional relationship between the requested torque and the actual required output torque. By amplifying the target requested torque issued by the controller of the advanced driver assistance system according to the steering needs according to the above proportional relationship, the obtained torque is the torque that the electronic power steering system actually needs to output to control the vehicle to turn according to navigation, which is the above-mentioned target assist torque.

[0089] Step S302: Determine the actual assist torque based on the assist torque limit value and the target assist torque.

[0090] In step S302 above, since the assist torque limit value can ensure that the vehicle is always in a state where the driver can control the steering, and the target assist torque is the assist torque that the electronic power steering system needs to output for actual steering, the assist torque actually output by the electronic power steering system can be coordinated to ensure that the vehicle is in a state where the driver can control the steering, while maximizing the satisfaction of the vehicle's actual steering needs, which is the actual assist torque mentioned above.

[0091] Optionally, in one specific embodiment, step S302 above includes steps S3021 to S3022:

[0092] Step S3021: If the target assist torque is less than or equal to the assist torque limit value, the target assist torque is determined as the actual assist torque.

[0093] In step S3021 above, when the assist torque is less than or equal to the assist torque limit value, it means that the assist torque required to control the vehicle to turn according to navigation does not exceed the assist torque range that ensures the vehicle is in a driver-controllable steering state. Therefore, the above target assist torque can be determined as the actual assist torque, that is, the electronic power steering system can be controlled to output assist torque directly according to the steering needs.

[0094] Step S3022: If the target assist torque is greater than the assist torque limit value, the assist torque limit value is determined as the actual assist torque.

[0095] In step S3022 above, when the assist torque is greater than the assist torque limit value, it means that the assist torque required to control the vehicle to turn according to the navigation exceeds the assist torque range that ensures the vehicle is in a driver-controllable steering state. Therefore, in order to avoid the driver being unable to manually control the vehicle steering when the EPS malfunctions instead of the expected maximum steering torque output, the above assist torque limit value needs to be determined as the actual assist torque value, that is, the electronic power steering system can be controlled to output the assist torque directly according to the assist torque limit value.

[0096] In the above embodiments, by controlling the electronic power steering system to output the power steering torque directly according to the target power steering torque when the target power steering torque is less than or equal to the power steering torque limit value, and controlling the electronic power steering system to output the power steering torque according to the power steering torque limit value when the target power steering torque is greater than the power steering torque limit value, it can be ensured that the vehicle is always in a state of driver-controllable steering and meet the actual steering needs of the vehicle to the maximum extent, thereby effectively balancing effective steering assistance and vehicle controllability.

[0097] Alternatively, in one specific implementation, such as Figure 3 As shown, the vehicle steering control method provided in this embodiment of the invention further includes step S3023 after step S3022, and step S400 specifically includes step S401.

[0098] Step S3023: Obtain the active steering torque emitted by the driver through the steering wheel.

[0099] In step S3022 above, when a fault occurs, if the calculated target assist torque is greater than the assist torque limit value, the electronic power steering system will output assist torque according to the assist torque limit value. At this time, the fault warning light will be displayed on the vehicle instrument panel. This makes the assist torque output by the electronic power steering system according to the request torque signal issued by the ADAS controller less than the target assist torque actually required for vehicle steering. At this time, the driver needs to actively output steering torque by controlling the steering wheel and make up the difference between the target assist torque and the assist torque limit value. Thus, the steering torque issued by the driver through the steering wheel is obtained, which is the above-mentioned active steering torque.

[0100] Step S401: Control the vehicle to steer according to the actual assist torque and the active steering torque.

[0101] In step S401 above, the electronic power steering system is controlled to output power torque according to the actual power torque to control the vehicle steering. At the same time, the vehicle steering is directly controlled according to the active steering torque generated by the driver turning the steering wheel, thereby jointly controlling the vehicle to turn according to the navigation line.

[0102] Please see Figure 5This diagram illustrates a vehicle steering control strategy provided by an embodiment of the present invention. Figure 5 As shown, the ADAS controller first sends the target requested torque to the EPS. The EPS receives the target requested torque and calculates the target assist torque required for the NOH function through its internal NOH assist torque calculation module. At the same time, the EPS determines the NOH assist torque limit value at that vehicle speed through the vehicle speed signal. Then, the EPS compares the calculated NOH target assist torque with the NOH assist torque limit value at that vehicle speed. If the calculated NOH target assist torque is greater than the NOH assist torque limit value at that vehicle speed, the NOH assist torque limit value at that vehicle speed is used as the final actual assist torque. If the calculated NOH target assist torque is less than the NOH assist torque limit value at that vehicle speed, the calculated NOH target assist torque is used as the final actual assist torque. Then, the EPS provides assistance based on the final actual assist torque, thereby realizing the vehicle's steering and keeping the vehicle within the designated lane.

[0103] Another object of the present invention is to provide a vehicle steering control device, wherein, please refer to Figure 6 , Figure 6 A schematic diagram of a vehicle steering control device according to an embodiment of the present invention is shown. The device includes:

[0104] The first acquisition module 61 is used to acquire the current speed and target requested torque of the vehicle when the vehicle is in an automatic assisted navigation driving state and it is determined that the vehicle needs to turn.

[0105] The first determining module 62 is used to determine the assist torque limit value based on the current vehicle speed; wherein, the assist torque limit value is the upper limit value of the assist torque at the current vehicle speed, which allows the driver to control the vehicle steering in the opposite direction to the assist torque.

[0106] The second determining module 63 is used to determine the actual assist torque based on the assist torque limit value and the target requested torque;

[0107] The control module 64 is used to control the vehicle to steer based on the actual assist torque.

[0108] In the system described in this embodiment of the invention, when the vehicle is in an automatic assisted navigation driving state, if it is determined that the vehicle needs to turn, the current vehicle speed and the target requested torque are obtained; based on the current vehicle speed, an assist torque limit value is determined; wherein, the assist torque limit value is the upper limit of the assist torque that the driver can use to control the vehicle's steering in the opposite direction to the assist torque at the current vehicle speed; based on the assist torque limit value and the target requested torque, the actual assist torque is determined; based on the actual assist torque, the vehicle is controlled to steer. Because the assist torque limit value is determined based on the vehicle's current speed, which is directly related to the difficulty of the driver controlling the vehicle's steering, and the actual assist torque is determined based on the target requested torque required for the vehicle's actual steering, combined with the aforementioned assist torque limit value, the assisted steering demand can be effectively balanced and the vehicle can be kept in a controllable state.

[0109] Optionally, in the control device, the second determining module 63 includes:

[0110] The first determining unit is used to determine the target assist torque based on the target requested torque;

[0111] The second determining unit is used to determine the actual assist torque based on the assist torque limit value and the target assist torque.

[0112] Optionally, in the control device, the vehicle stores a correspondence between vehicle speed and assist torque limit value;

[0113] The first determining module 61 is specifically used to determine the assist torque limit value based on the current vehicle speed and the corresponding relationship.

[0114] Optionally, in the control device, the second determining unit includes:

[0115] The first determining subunit is used to determine the target assist torque as the actual assist torque when the target assist torque is less than or equal to the assist torque limit value;

[0116] The second determining subunit is used to determine the assist torque limit value as the actual assist torque when the target assist torque is greater than the assist torque limit value.

[0117] Optionally, the device further includes:

[0118] The second acquisition module is used to acquire the active steering torque emitted by the driver through the steering wheel after determining the assist torque limit value as the actual assist torque when the target assist torque is greater than the assist torque limit value.

[0119] The control module is specifically used to control the vehicle to steer based on the actual assist torque and the active steering torque.

[0120] Another object of the present invention is to provide a vehicle, wherein the vehicle further includes the aforementioned vehicle steering control device.

[0121] The present invention also proposes a readable storage medium, wherein a program or instructions are stored on the readable storage medium, and when the program or instructions are executed by a processor, the vehicle steering control method as described above is implemented.

[0122] The present invention also provides a chip, the chip including a processor and a communication interface, the communication interface being coupled to the processor, the processor being used to run programs or instructions to implement the vehicle steering control method as described above.

[0123] The vehicle, readable storage medium, and chip described above have the same advantages over the prior art as the aforementioned vehicle steering control method and device, and will not be repeated here.

[0124] In summary, the vehicle steering control method, device, vehicle, and readable storage medium provided by this invention, when the vehicle is in an automated assisted navigation driving state, if it is determined that the vehicle needs to turn, acquires the vehicle's current speed and target requested torque; determines an assist torque limit value based on the current speed; wherein the assist torque limit value is the upper limit of the assist torque that the driver can control the vehicle to steer in the opposite direction to the assist torque at the current speed; determines the actual assist torque based on the assist torque limit value and the target requested torque; and controls the vehicle to steer based on the actual assist torque. Because the assist torque limit value is determined based on the vehicle's current speed, which is directly related to the difficulty of the driver controlling the vehicle's steering, and the actual assist torque is determined based on the target requested torque required for the vehicle's actual steering in combination with the aforementioned assist torque limit value, the assisted steering demand can be effectively balanced and the vehicle can be kept in a controllable state.

[0125] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0126] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0127] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A vehicle steering control method characterized by, The method includes: When the vehicle is in an automatic assisted navigation driving state, if it is determined that the vehicle needs to turn, the current speed of the vehicle and the target requested torque are obtained. Based on the current vehicle speed, a power assist torque limit value is determined; wherein, the power assist torque limit value is the upper limit value of the power assist torque at the current vehicle speed, which allows the driver to control the vehicle steering in the direction opposite to the power assist torque. The actual assist torque is determined based on the assist torque limit value and the target requested torque; The vehicle is steered according to the actual assist torque. The vehicle stores a correspondence between vehicle speed and power assist torque limit values; the process of determining the correspondence includes: Determine the minimum turning radius at different vehicle speeds and at each of the stated vehicle speeds; Set the target assist torque for the NOH function, and activate the NOH function to control the vehicle's movement based on the vehicle speed and the minimum turning radius at that speed. Turn off the vehicle's NOH function and inject the maximum requested NOH torque; If the driver is unable to keep the vehicle within the lane, return to the steps for setting the NOH function target assist torque and reduce the NOH function target assist torque. If the driver can keep the vehicle within the lane, then the target assist torque is taken as the assist torque limit value at the vehicle speed. Based on the current vehicle speed, determine the assist torque limit value, including: The assist torque limit value is determined based on the current vehicle speed and the corresponding relationship.

2. The steering control method according to claim 1, characterized by, Determining the actual assist torque based on the assist torque limit value and the target requested torque includes: Determine the target assist torque based on the target requested torque; The actual assist torque is determined based on the assist torque limit value and the target assist torque.

3. The steering control method according to claim 1, characterized in that, Determining the actual assist torque based on the assist torque limit value and the target assist torque includes: If the target assist torque is less than or equal to the assist torque limit value, the target assist torque is determined as the actual assist torque; If the target assist torque is greater than the assist torque limit value, the assist torque limit value is determined as the actual assist torque.

4. The steering control method according to claim 3, characterized in that, After determining the actual assist torque as the assist torque limit value when the target assist torque is greater than the assist torque limit value, the method further includes: It can acquire the active steering torque emitted by the driver through the steering wheel; Based on the actual assist torque, control the vehicle to steer, including: The vehicle is steered according to the actual assist torque and the active steering torque.

5. A vehicle steering control device, characterized in that, The device includes: The first acquisition module is used to acquire the vehicle's current speed and target requested torque when the vehicle is in an automatic assisted navigation driving state and it is determined that the vehicle needs to turn. The first determining module is used to determine the assist torque limit value based on the current vehicle speed; wherein, the assist torque limit value is the upper limit value of the assist torque at the current vehicle speed, which allows the driver to control the vehicle steering in the opposite direction to the assist torque. The second determining module is used to determine the actual assist torque based on the assist torque limit value and the target requested torque; The control module is used to control the vehicle to steer based on the actual assist torque; The vehicle stores the correspondence between vehicle speed and assist torque limit values; The process of determining the correspondence includes: Determine the minimum turning radius at different vehicle speeds and at each of the stated vehicle speeds; Set the target assist torque for the NOH function, and activate the NOH function to control the vehicle's movement based on the vehicle speed and the minimum turning radius at that speed. Turn off the vehicle's NOH function and inject the maximum requested NOH torque; If the driver is unable to keep the vehicle within the lane, return to the steps for setting the NOH function target assist torque and reduce the NOH function target assist torque. If the driver can keep the vehicle within the lane, then the target assist torque is taken as the assist torque limit value at the vehicle speed. The first determining module is specifically used to determine the assist torque limit value based on the current vehicle speed and the corresponding relationship.

6. The control device according to claim 5, characterized in that, The second determining module includes: The first determining unit is used to determine the target assist torque based on the target requested torque; The second determining unit is used to determine the actual assist torque based on the assist torque limit value and the target assist torque.

7. The control device according to claim 6, characterized in that, The second determining unit includes: The first determining subunit is used to determine the target assist torque as the actual assist torque when the target assist torque is less than or equal to the assist torque limit value; The second determining subunit is used to determine the assist torque limit value as the actual assist torque when the target assist torque is greater than the assist torque limit value.

8. The control device according to claim 7, characterized in that, The device further includes: The second acquisition module is used to acquire the active steering torque emitted by the driver through the steering wheel after determining the assist torque limit value as the actual assist torque when the target assist torque is greater than the assist torque limit value. The control module is specifically used to control the vehicle to steer based on the actual assist torque and the active steering torque.

9. A vehicle, characterized in that, The vehicle also includes a vehicle steering control device as described in any one of claims 5 to 8.

10. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the vehicle steering control method according to any one of claims 1 to 4.

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