Vehicle control mode determination method and device, electronic equipment and storage medium

Abstract

The invention discloses a vehicle control mode determination method and device, electronic equipment and a storage medium, and relates to the technical field of vehicle control. The method comprises the following steps: acquiring a vehicle state of a vehicle at a target moment; according to the maximum slip rate of each wheel of the vehicle at the target moment, the maximum additional yawing moment capable of being provided by each wheel at the target moment is determined; the wheel with the actual slip rate not exceeding the maximum slip rate at the target moment serves as a target wheel; according to the vehicle state and the maximum additional yawing moment capable of being provided by the target wheel, the control mode of the vehicle is determined, and the control mode is used for controlling the longitudinal acceleration of the vehicle to be kept unchanged or change according to the target trend by adjusting the driving force and / or braking force of the target wheel. The technical problem that in the prior art, when the yaw stability of the vehicle is controlled through differential braking, the vehicle control smoothness is poor is solved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular, to a method, device, electronic device and storage medium for determining a vehicle control mode. Background Art

[0002] Electronic stability program is an important part of the current automotive active safety technology, and vehicle dynamics control is one of its important functions. In the existing vehicle dynamics control system, the control of vehicle yaw stability is mainly achieved through differential braking.

[0003] When the vehicle is in an understeer state, the inner wheel is braked to generate an additional yaw moment to increase the yaw; when the vehicle is in an oversteer state, the outer wheel is braked to generate an additional yaw moment to reduce the yaw. However, due to the limitation of road adhesion, the additional yaw moment that each wheel of the vehicle can provide varies with the slip rate of the wheel, and can only provide effective additional yaw moment within a certain range, and the adjustment range is limited; and since only the wheels are braked, the speed of the vehicle will change, which has a greater impact on the smoothness of control under extreme conditions.

[0004] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0005] The embodiments of the present application provide a method, device, electronic device and storage medium for determining a vehicle control mode, so as to at least solve the technical problem of poor vehicle control smoothness when controlling the vehicle yaw stability through differential braking in the prior art.

[0006] According to one aspect of an embodiment of the present application, a method for determining a vehicle control mode is provided, comprising: obtaining a vehicle state at a target moment; determining a maximum additional yaw moment that each wheel can provide at the target moment based on a maximum slip rate of each wheel of the vehicle at the target moment; taking a wheel whose actual slip rate does not exceed the maximum slip rate at the target moment as a target wheel; determining a vehicle control mode based on the vehicle state and the maximum additional yaw moment that the target wheel can provide, wherein the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or to change according to a target trend by adjusting the driving force and / or braking force of the target wheel.

[0007] Optionally, obtaining the vehicle state of the vehicle at the target time includes: obtaining a throttle sensor signal and a brake sensor signal of the vehicle at the target time; and determining the vehicle state according to the throttle sensor signal and the brake sensor signal, wherein the vehicle state is any one of the following three states:

[0008] The first state indicates that the vehicle is in a state where the accelerator and brake are not working at the same time;

[0009] The second state indicates that the vehicle is in a state where the accelerator is working and the brake is not working;

[0010] The third state indicates that the vehicle is in a state where the accelerator is not working and the brake is working.

[0011] Optionally, the control mode of the vehicle is determined according to the vehicle state and the maximum additional yaw moment that can be provided by the target wheel, including: determining the driver's expected additional yaw moment for the target wheel at the target moment according to the vehicle state at the target moment and the driver's expected driving state of the vehicle at the target moment; determining the control mode of the vehicle according to the vehicle state, the maximum additional yaw moment that can be provided by the target wheel at the target moment, and the expected additional yaw moment.

[0012] Optionally, the control mode of the vehicle is determined based on the vehicle state, the maximum additional yaw moment that the target wheels can provide at the target moment, and the expected additional yaw moment, including: when the vehicle state is the second state and the maximum additional yaw moment that all the target wheels can provide at the target moment is greater than or equal to the expected additional yaw moment, determining the driving force control mode as the control mode of the vehicle, wherein the driving force control mode is used to reduce the output torque corresponding to the target wheels on one side of the vehicle, and increase the output torque corresponding to the target wheels on the other side, so as to control the vehicle by applying driving force.

[0013] Optionally, the control mode of the vehicle is determined according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target moment, and the expected additional yaw moment, including: when the vehicle state is the first state or the second state, and the maximum additional yaw moment that any target wheel can provide at the target moment is less than the expected additional yaw moment, determining the collaborative control mode as the control mode of the vehicle, wherein the collaborative control mode is used to apply driving force and braking force to the target wheels on different sides respectively to control the vehicle.

[0014] Optionally, the control mode of the vehicle is determined according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target moment, and the expected additional yaw moment, including: when the vehicle state is any one of the first state, the second state, and the third state, and the braking signal value of the vehicle is greater than a preset threshold or the longitudinal force demand signal value of the vehicle is greater than a preset warning value, determining the braking force control mode as the control mode of the vehicle, wherein the braking force control mode is used to control the vehicle by applying braking force to the target wheel in the absence of driving force on the target wheel.

[0015] Optionally, after determining the vehicle control mode based on the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, the method for determining the vehicle control mode also includes: determining the expected driving force and / or expected braking force required for the target wheel under the determined control mode based on the expected additional yaw moment of the target wheel and the lever arm from the wheel end to the center of mass of the target wheel.

[0016] Optionally, the method for determining the vehicle control mode also includes: when it is detected that the actual slip rate of the i-th wheel of the vehicle at the target moment exceeds a slip rate threshold, reducing the actual slip rate of the i-th wheel by adjusting the driving force or braking force applied to the i-th wheel, wherein i is a positive integer and the slip rate threshold is less than the maximum slip rate of the i-th wheel.

[0017] Optionally, the driving force and / or braking force of the target wheel is adjusted through the control mode to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend, including: determining the expected longitudinal force of the target wheel at the target time according to the expected additional yaw moment of the target wheel at the target time; obtaining the actual longitudinal force of the target wheel at the target time; adjusting the driving force and / or braking force of the target wheel according to the difference between the expected longitudinal force and the actual longitudinal force, to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend.

[0018] Optionally, according to the difference between the expected longitudinal force and the actual longitudinal force, the driving force and / or braking force of the target wheel is adjusted to control the longitudinal acceleration of the vehicle to remain unchanged or change according to a target trend, including: when it is detected that the difference between the expected longitudinal force and the actual longitudinal force is greater than a target threshold, the driving force and / or braking force of the target wheel is adjusted to control the longitudinal acceleration of the vehicle to decrease according to the target trend; when it is detected that the difference between the expected longitudinal force and the actual longitudinal force is less than or equal to the target threshold, the driving force and / or braking force of the target wheel is adjusted to control the longitudinal acceleration of the vehicle to remain unchanged.

[0019] According to another aspect of the present application, a device for determining a vehicle control mode is also provided, which includes: an acquisition unit for acquiring a vehicle state at a target moment; a first determination unit for determining a maximum additional yaw moment that each wheel can provide at the target moment based on a maximum slip rate of each wheel of the vehicle at the target moment; a first processing unit for taking a wheel whose actual slip rate does not exceed the maximum slip rate at the target moment as a target wheel; and a second determination unit for determining a vehicle control mode based on the vehicle state and the maximum additional yaw moment that the target wheel can provide, wherein the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or change according to a target trend by adjusting the driving force and / or braking force of the target wheel.

[0020] According to another aspect of the present application, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer-readable storage medium, wherein when the computer program runs, the device where the computer-readable storage medium is located executes the above-mentioned method for determining the vehicle control mode.

[0021] According to another aspect of the present application, an electronic device is also provided, wherein the electronic device includes one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by one or more processors, the one or more processors execute the above-mentioned method for determining the vehicle control mode.

[0022] In the present application, the vehicle state at the target time is first obtained, and then the maximum additional yaw moment that each wheel can provide at the target time is determined according to the maximum slip rate of each wheel of the vehicle at the target time. The wheel whose actual slip rate does not exceed the maximum slip rate at the target time is used as the target wheel, and the control mode of the vehicle is determined according to the vehicle state and the maximum additional yaw moment that the target wheel can provide, wherein the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend by adjusting the driving force and / or braking force of the target wheel.

[0023] As can be seen from the above content, the method for determining the vehicle control mode provided by the present application, by real-time acquisition of the vehicle state and combining the maximum slip rate of the wheel, intelligently selects the most appropriate control mode, effectively improving the vehicle's handling and safety. Under different driving conditions, the method can flexibly adjust the driving force and braking force to ensure that the longitudinal acceleration of the vehicle meets the driver's expectations, while avoiding excessive wheel slip, improving the stability and response speed of the vehicle under complex road conditions, and providing the driver with a safer and more comfortable driving experience. In addition, the present application determines the slip rate limit (i.e., the maximum slip rate) of each wheel and the maximum additional yaw moment that each wheel can provide, while ensuring the smoothness of intervention control as much as possible and reducing the loss of the brake disc, and through the determined control mode, maximizes the use of the additional yaw moment that the driving force can provide to control the understeering and oversteering states of the vehicle, thereby controlling the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend, thereby solving the technical problem of poor vehicle control smoothness when controlling the yaw stability of the vehicle by differential braking in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0025] Figure 1 is a flow chart of an optional method for determining a vehicle control mode according to an embodiment of the present application;

[0026] Figure 2 is a flow chart of an optional vehicle control method according to an embodiment of the present application;

[0027] Figure 3 is a schematic diagram of a driving condition and a braking condition of each wheel in an oversteering condition according to an embodiment of the present application;

[0028] Figure 4 is a schematic diagram of a driving condition and a braking condition of each wheel in an understeering condition according to an embodiment of the present application;

[0029] Figure 5 It is a schematic diagram of an optional vehicle control mode determination device according to an embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0032] It should also be noted that the information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) collected by this application are information and data authorized by the user or fully authorized by all parties, and the collection, storage, use, processing, transmission, provision, disclosure and application of relevant data are in compliance with the relevant laws, regulations and standards of the relevant regions, necessary confidentiality measures are taken, and public order and good customs are not violated, and corresponding operation portals are provided for users to choose to authorize or refuse. For example, an interface is set up between this system and relevant users or organizations. Before obtaining relevant information, it is necessary to send an acquisition request to the aforementioned user or organization through the interface, and obtain relevant information after receiving the consent information fed back by the aforementioned user or organization.

[0033] According to an embodiment of the present application, an embodiment of a method for determining a vehicle control mode is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0034] Figure 1 is a flow chart of an optional method for determining a vehicle control mode according to an embodiment of the present application, such as Figure 1 As shown, the method comprises the following steps:

[0035] Step S101, obtaining the vehicle status at the target time.

[0036] Optionally, in step S101, the target time is any time, for example, the target time may be the current time or a time in the future.

[0037] In an optional embodiment, a vehicle control system can be used as the execution subject of the method for determining the vehicle control mode in the embodiment of the present application, wherein the vehicle control system can be a software system or an embedded system combining software and hardware. It should be noted that the method for determining the vehicle control mode in the embodiment of the present application can also use other forms of execution subjects, such as a device or an apparatus, and the present application does not specifically limit the form of expression of the execution subject.

[0038] For the sake of convenience, the following description uses the vehicle control system as the execution subject.

[0039] Optionally, Figure 2 is a flow chart of an optional vehicle control method according to an embodiment of the present application, such as Figure 2As shown, the vehicle control system can determine the vehicle state (i.e., the vehicle state) of the vehicle based on the signal transmitted by the accelerator sensor and the signal transmitted by the brake sensor on the vehicle. Figure 2 The vehicle status includes: S1 status (no throttle, no brake), S2 status (throttle but no brake); S3 status (brake but no throttle).

[0040] Step S102: determining the maximum additional yaw moment that each wheel can provide at the target time according to the maximum slip rate of each wheel of the vehicle at the target time.

[0041] Alternatively, if Figure 2 As shown, the vehicle control system can first determine the slip rate-additional yaw moment curve of each wheel, and then determine the maximum additional yaw moment that can be provided by the slip rate limit (i.e., maximum slip rate) of each wheel and the driving and braking forces (i.e., driving force and braking force) at the current slip rate according to the relationship between the slip rate-additional yaw moment curves of each wheel.

[0042] It should be noted that the slip rate-driving force additional yaw moment relationship curves of different wheels may not be consistent, so it is necessary to calculate the slip rate limit and the maximum additional yaw moment when each wheel applies driving force.

[0043] Similarly, the slip ratio-braking force additional yaw moment relationship curves of different wheels may also be inconsistent, so it is necessary to calculate the slip ratio limit and the maximum additional yaw moment when the braking force is applied to each wheel.

[0044] Step S103, taking the wheel whose actual slip rate does not exceed the maximum slip rate at the target moment as the target wheel.

[0045] Optionally, when the target time arrives, firstly detect whether the actual slip rate of each wheel exceeds the maximum slip rate of the wheel, if the actual slip rate of a wheel exceeds the maximum slip rate of the wheel, then no driving force and braking force are allocated to the wheel. If the actual slip rate of a wheel does not exceed the maximum slip rate of the wheel, then the wheel is used as the target wheel.

[0046] Step S104, determining the control mode of the vehicle according to the vehicle state and the maximum additional yaw moment that the target wheel can provide.

[0047] Optionally, in step S104, the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or change according to a target trend by adjusting the driving force and / or braking force of the target wheel.

[0048] Optionally, when determining the control mode of the vehicle, in order to ensure smooth control, if a smaller change in longitudinal force can meet the expected additional yaw moment requirement, the current longitudinal acceleration of the vehicle should be maintained as much as possible, that is, if one side increases, the other side decreases accordingly, thereby maintaining the total longitudinal force; if a larger longitudinal force change is required, in order to ensure safety, the longitudinal acceleration ax should be decreased as smoothly as possible, that is, a smooth change of the longitudinal force should be ensured.

[0049] Based on the contents of the above steps S101 to S104, it can be known that in the present application, the vehicle state at the target time is first obtained, and then the maximum additional yaw moment that each wheel can provide at the target time is determined according to the maximum slip rate of each wheel of the vehicle at the target time. The wheel whose actual slip rate does not exceed the maximum slip rate at the target time is taken as the target wheel, and the control mode of the vehicle is determined according to the vehicle state and the maximum additional yaw moment that the target wheel can provide, wherein the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend by adjusting the driving force and / or braking force of the target wheel.

[0050] As can be seen from the above content, the method for determining the vehicle control mode provided by the present application, by real-time acquisition of the vehicle state and combining the maximum slip rate of the wheel, intelligently selects the most appropriate control mode, effectively improving the vehicle's handling and safety. Under different driving conditions, the method can flexibly adjust the driving force and braking force to ensure that the longitudinal acceleration of the vehicle meets the driver's expectations, while avoiding excessive wheel slip, improving the stability and response speed of the vehicle under complex road conditions, and providing the driver with a safer and more comfortable driving experience. In addition, the present application determines the slip rate limit (i.e., the maximum slip rate) of each wheel and the maximum additional yaw moment that each wheel can provide, while ensuring the smoothness of intervention control as much as possible and reducing the loss of the brake disc, and through the determined control mode, maximizes the use of the additional yaw moment that the driving force can provide to control the understeering and oversteering states of the vehicle, thereby controlling the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend, thereby solving the technical problem of poor vehicle control smoothness when controlling the yaw stability of the vehicle by differential braking in the prior art.

[0051] In an optional embodiment, the vehicle control system may obtain a throttle sensor signal and a brake sensor signal of the vehicle at the target time, and then determine the vehicle state according to the throttle sensor signal and the brake sensor signal, wherein the vehicle state is any one of the following three states:

[0052] The first state indicates that the vehicle is in a state where the accelerator and brake are not working at the same time;

[0053] The second state indicates that the vehicle is in a state where the accelerator is working and the brake is not working;

[0054] The third state indicates that the vehicle is in a state where the accelerator is not working and the brake is working.

[0055] It should be noted that this method of real-time monitoring of vehicle status can help the vehicle control system respond quickly to the driver's operating intentions, whether accelerating, decelerating or maintaining a constant speed, to ensure that the vehicle's driving status meets the driver's expectations and improve the driving experience.

[0056] In an optional embodiment, the control mode of the vehicle is determined according to the vehicle state and the maximum additional yaw moment that the target wheel can provide, including: first, according to the vehicle state at the target time and the driver's expected driving state of the vehicle at the target time, determining the driver's expected additional yaw moment for the target wheel at the target time. Then, according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, determining the control mode of the vehicle.

[0057] Alternatively, if Figure 2 As shown in FIG. 1 , for a target wheel that does not exceed the slip rate limit, the vehicle control system may determine the desired additional yaw moment Mz for the target wheel according to the vehicle state Si (i=1, 2, 3) and the desired driving state of the vehicle. Tar Then, according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment Mz Tar , determine the control mode of the vehicle. Among them, Figure 2 It is also shown in FIG. 1 that the reference factor for determining the control mode of the vehicle also includes the longitudinal acceleration ax of the vehicle.

[0058] It should be noted that this method can intelligently select the most appropriate control strategy based on the driver's specific needs and the vehicle's actual capabilities. It not only improves the vehicle's handling flexibility, but also provides more effective vehicle control in emergency situations, such as preventing skidding when turning at high speed, thereby improving driving safety.

[0059] In an optional embodiment, determining the control mode of the vehicle according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment includes:

[0060] When the vehicle is in the second state and the maximum additional yaw moment that can be provided by all the target wheels at the target moment is greater than or equal to the expected additional yaw moment, the driving force control mode is determined to be the control mode of the vehicle, wherein the driving force control mode is used to reduce the output torque corresponding to the target wheels on one side of the vehicle, and increase the output torque corresponding to the target wheels on the other side, so as to control the vehicle by applying driving force.

[0061] Alternatively, if Figure 2 As shown, when the vehicle state is S2 state (i.e., the second state mentioned above), if the differential drive can meet the demand for the expected additional yaw moment (i.e., the maximum additional yaw moment that all the target wheels can provide at the target time is greater than or equal to the expected additional yaw moment), in order to maintain the longitudinal acceleration ax of the vehicle or ensure smooth changes in ax, the torque of the target wheel on one side can be reduced (i.e., the output torque corresponding to the target wheel on one side of the vehicle is reduced), and the torque of the target wheel on the other side can be increased (i.e., the output torque corresponding to the target wheel on the other side is increased). At this time, the control mode of the vehicle is the driving force control mode.

[0062] It should be noted that if the driving force of the target wheel cannot meet the demand of the expected additional yaw torque, additional braking force can be added to the target wheel on the torque reduction side (that is, the target wheel on the side where the torque reduction operation is performed). At this time, the vehicle control mode is the collaborative control mode; when the braking force demand is large, in order to ensure safety, the collaborative control mode should be gradually switched to the braking force control mode.

[0063] It should also be noted that in situations where the direction of the vehicle needs to be adjusted but deceleration is not desired, such as making a quick turn on a track, this control mode can effectively utilize the driving force of the wheels to achieve precise steering control while maintaining the vehicle's high-speed driving state. Moreover, while ensuring the smoothness of intervention control and reducing the loss of brake discs as much as possible, the coordinated control of differential drive and differential braking can maximize the use of the additional yaw torque provided by the driving force to control the understeering and oversteering states of the vehicle, reduce the loss of brake discs caused by braking force, and improve the economy of the vehicle.

[0064] In an optional embodiment, determining the control mode of the vehicle according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment further includes:

[0065] When the vehicle is in the first state or the second state and the maximum additional yaw moment that can be provided by any target wheel at the target moment is less than the expected additional yaw moment, the collaborative control mode is determined as the control mode of the vehicle, wherein the collaborative control mode is used to apply driving force and braking force to the target wheels on different sides respectively to control the vehicle.

[0066] Alternatively, if Figure 2As shown, when the vehicle state is S1 state (corresponding to the first state mentioned above) or S2 state (corresponding to the second state mentioned above), if the maximum additional yaw moment of the target wheel cannot meet the expected additional yaw moment of the target wheel, the collaborative control mode is entered. Specifically, if the driving force of the target wheel cannot meet the demand of the expected additional yaw moment, the braking force can be added to the torque reduction side wheel. At this time, the control mode of the vehicle is the collaborative control mode.

[0067] In an optional embodiment, the control mode of the vehicle is determined according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, including: when the vehicle state is any one of the first state, the second state, and the third state, and the braking signal value of the vehicle is greater than a preset threshold or the longitudinal force demand signal value of the vehicle is greater than a preset warning value, determining the braking force control mode as the control mode of the vehicle, wherein the braking force control mode is used to control the vehicle by applying braking force to the target wheel when there is no driving force on the target wheel.

[0068] Alternatively, if Figure 2 As shown, in any of the S1, S2 and S3 states, if the driver's foot brake force is too large (that is, the vehicle's brake signal value is greater than the preset threshold) or the vehicle's longitudinal force demand is large (that is, the vehicle's longitudinal force demand signal value is greater than the preset warning value), the braking force control mode is entered. In the braking force control mode, driving force intervention should be avoided, and the desired additional yaw moment demand is met only by differential braking.

[0069] In an optional embodiment, after determining the vehicle control mode based on the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, the method for determining the vehicle control mode also includes: determining the expected driving force and / or expected braking force required for the target wheel under the determined control mode based on the expected additional yaw moment of the target wheel and the lever arm from the wheel end to the center of mass of the target wheel.

[0070] Optionally, when the target wheel does not exceed the slip rate limit, the desired additional yaw torque is first allocated to the driving force to maximize the use of the additional yaw torque that can be provided by the differential drive of the inner and outer wheels; when the maximum additional yaw torque that can be provided by the differential drive cannot meet the required additional yaw torque, additional braking force is added to provide the remaining desired additional yaw torque through differential braking of the inner and outer wheels.

[0071] Optionally, three control modes can be divided, namely, driving force control mode, cooperative control mode, and braking force control mode. In the driving force control mode, the control is performed only by increasing and decreasing torque; in the cooperative control mode, the driving force and the braking force are jointly controlled, and the braking and driving will not exist on the same side of the wheel at the same time; in the braking force control mode, the control is performed only by the braking force. The calculation formula for the expected driving force and / or expected braking force of the target wheel in each mode can refer to the following formula (1):

[0072]

[0073] In formula (1), l is the force arm from the wheel end to the center of mass of the target wheel, ΔF d is the desired driving force, ΔF b is the desired braking force, Mz Tar is the desired additional yaw moment of the target wheel.

[0074] It should be noted that the maximum additional yaw moment = maximum driving additional yaw moment + maximum braking additional yaw moment, which can be specifically referred to in the following formula (2):

[0075]

[0076] In formula (2), Mz max is the maximum additional yaw moment, is the maximum drive additional yaw moment, The maximum braking additional yaw moment.

[0077] It should also be noted that formula (3) shows that when the vehicle is oversteering, The calculation formula for understeering of the vehicle Formula (4) shows the calculation formula for when the vehicle is oversteering. The calculation formula for understeering of the vehicle The calculation formula for .

[0078]

[0079] Optionally, are the maximum driving additional yaw torque that each wheel can provide; are the maximum braking additional yaw moments that each wheel can provide.

[0080] Optionally, Figure 3 is a schematic diagram of a driving condition and a braking condition of each wheel in an oversteering condition according to an embodiment of the present application, Figure 4is a schematic diagram of the driving and braking conditions of each wheel in an understeering condition according to an embodiment of the present application. Figure 3 and Figure 4 middle, They are the slip rate limits for each wheel drive respectively; They are the slip rate limits of each wheel during braking.

[0081] In an optional embodiment, when it is detected that the actual slip rate of the i-th wheel of the vehicle at the target moment exceeds a slip rate threshold, the actual slip rate of the i-th wheel is reduced by adjusting the driving force or braking force applied to the i-th wheel, wherein i is a positive integer and the slip rate threshold is less than the maximum slip rate of the i-th wheel.

[0082] Optionally, during the vehicle control process, the wheels should be prevented from exceeding the maximum slip rate as much as possible. Therefore, in the technical solution of the present application, a corresponding slip rate threshold is set for each wheel, wherein the slip rate threshold of each wheel is less than the maximum slip rate of the wheel. For example, the slip rate threshold may be the product of the maximum slip rate and a preset coefficient, wherein the preset coefficient is a value greater than 0 and less than 1. When it is detected that the actual slip rate of a wheel exceeds the slip rate threshold of the wheel, the driving force or braking force applied to the wheel may be adjusted to reduce the actual slip rate of the wheel as quickly as possible, thereby ensuring the driving safety of the vehicle.

[0083] In an optional embodiment, the driving force and / or braking force of the target wheel is adjusted through a control mode to control the longitudinal acceleration of the vehicle to remain unchanged or change according to a target trend, including: determining the expected longitudinal force of the target wheel at the target moment according to the expected additional yaw moment of the target wheel at the target moment; obtaining the actual longitudinal force of the target wheel at the target moment; adjusting the driving force and / or braking force of the target wheel according to the difference between the expected longitudinal force and the actual longitudinal force, to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend.

[0084] Alternatively, if Figure 2 As shown, during the vehicle control process, it is necessary to maintain the longitudinal acceleration of the vehicle as constant as possible or to descend smoothly according to the target trend. At the same time, it is also necessary to avoid the existence of driving force and braking force on the same wheel at the same time.

[0085] Optionally, in order to ensure the smoothness of vehicle control, if a smaller longitudinal force change can meet the expected additional yaw moment requirement, the current longitudinal acceleration should be maintained as much as possible, that is, if one side increases, the other side will decrease accordingly, so as to maintain the total longitudinal force; if a larger longitudinal force change is required, in order to ensure safety, the longitudinal acceleration ax should be allowed to decrease smoothly as much as possible, that is, to ensure a smooth change of the longitudinal force.x With driving force F d Braking force F d The relationship between can be referred to in the following formula (5).

[0086] ma x =F d -F d (5)

[0087] The specific adjustment process can be referred to as follows:

[0088] When it is detected that the difference between the expected longitudinal force and the actual longitudinal force is greater than the target threshold, the longitudinal acceleration of the vehicle is controlled to be reduced according to the target trend by adjusting the driving force and / or braking force of the target wheel; when it is detected that the difference between the expected longitudinal force and the actual longitudinal force is less than or equal to the target threshold, the longitudinal acceleration of the vehicle is controlled to remain unchanged by adjusting the driving force and / or braking force of the target wheel.

[0089] According to another aspect of an embodiment of the present application, a device for determining a vehicle control mode is also provided. Figure 5 is a schematic diagram of an optional vehicle control mode determination device according to an embodiment of the present application, such as Figure 5 As shown, the vehicle control mode determination device includes: an acquisition unit 501 , a first determination unit 502 , a first processing unit 503 , and a second determination unit 504 .

[0090] Optionally, the acquisition unit 501 is used to acquire the vehicle state at the target moment; the first determination unit 502 is used to determine the maximum additional yaw moment that each wheel can provide at the target moment according to the maximum slip rate of each wheel of the vehicle at the target moment; the first processing unit 503 is used to take the wheel whose actual slip rate does not exceed the maximum slip rate at the target moment as the target wheel; the second determination unit 504 is used to determine the control mode of the vehicle according to the vehicle state and the maximum additional yaw moment that can be provided by the target wheel, wherein the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend by adjusting the driving force and / or braking force of the target wheel.

[0091] Optionally, the acquisition unit 501 includes: a first acquisition subunit and a first determination subunit. The first acquisition subunit is used to acquire the throttle sensor signal and the brake sensor signal of the vehicle at the target time; the first determination subunit is used to determine the vehicle state according to the throttle sensor signal and the brake sensor signal, wherein the vehicle state is any one of the following three states:

[0092] The first state indicates that the vehicle is in a state where the accelerator and brake are not working at the same time;

[0093] The second state indicates that the vehicle is in a state where the accelerator is working and the brake is not working;

[0094] The third state indicates that the vehicle is in a state where the accelerator is not working and the brake is working.

[0095] Optionally, the second determination unit 504 includes: a second determination subunit and a third determination subunit. The second determination subunit is used to determine the driver's expected additional yaw moment for the target wheel at the target moment according to the vehicle state at the target moment and the driver's expected driving state of the vehicle at the target moment; the third determination subunit is used to determine the vehicle control mode according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target moment, and the expected additional yaw moment.

[0096] Optionally, the second determination unit 504 includes: a fourth determination subunit, used to determine the driving force control mode as the control mode of the vehicle when the vehicle state is the second state and the maximum additional yaw moment that can be provided by all target wheels at the target moment is greater than or equal to the expected additional yaw moment, wherein the driving force control mode is used to reduce the output torque corresponding to the target wheel on one side of the vehicle and increase the output torque corresponding to the target wheel on the other side, so as to control the vehicle by applying driving force.

[0097] Optionally, the second determination unit 504 includes: a fifth determination subunit, used to determine that the cooperative control mode is the control mode of the vehicle when the vehicle state is the first state or the second state and the maximum additional yaw moment that can be provided by any target wheel at the target moment is less than the expected additional yaw moment, wherein the cooperative control mode is used to apply driving force and braking force to the target wheels on different sides respectively to control the vehicle.

[0098] Optionally, the second determination unit 504 includes: a sixth determination subunit, used to determine that the braking force control mode is the control mode of the vehicle when the vehicle state is any one of the first state, the second state and the third state, and the braking signal value of the vehicle is greater than a preset threshold value or the longitudinal force demand signal value of the vehicle is greater than a preset warning value, wherein the braking force control mode is used to control the vehicle by applying braking force to the target wheel when there is no driving force on the target wheel.

[0099] Optionally, the vehicle control mode determination device also includes: a third determination unit, used to determine the expected driving force and / or expected braking force required for the target wheel under the determined control mode based on the expected additional yaw moment of the target wheel and the lever arm from the wheel end to the center of mass of the target wheel.

[0100] Optionally, the device for determining the vehicle control mode also includes: a second processing unit, used to reduce the actual slip rate of the i-th wheel by adjusting the driving force or braking force applied to the i-th wheel when it is detected that the actual slip rate of the i-th wheel of the vehicle at the target moment exceeds a slip rate threshold, wherein i is a positive integer and the slip rate threshold is less than the maximum slip rate of the i-th wheel.

[0101] Optionally, the second determination unit 504 further includes: a seventh determination subunit, a first acquisition subunit, and an adjustment subunit. The seventh determination subunit is used to determine the expected longitudinal force of the target wheel at the target moment according to the expected additional yaw moment of the target wheel at the target moment; the first acquisition subunit is used to obtain the actual longitudinal force of the target wheel at the target moment; and the adjustment subunit is used to adjust the driving force and / or braking force of the target wheel according to the difference between the expected longitudinal force and the actual longitudinal force, so as to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend.

[0102] Optionally, the adjustment subunit includes: a first control module and a second control module. The first control module is used to control the longitudinal acceleration of the vehicle to decrease according to the target trend by adjusting the driving force and / or braking force of the target wheel when it is detected that the difference between the expected longitudinal force and the actual longitudinal force is greater than the target threshold; the second control module is used to control the longitudinal acceleration of the vehicle to remain unchanged by adjusting the driving force and / or braking force of the target wheel when it is detected that the difference between the expected longitudinal force and the actual longitudinal force is less than or equal to the target threshold.

[0103] According to another aspect of the present application, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer-readable storage medium, wherein when the computer program runs, the device where the computer-readable storage medium is located executes the above-mentioned method for determining the vehicle control mode.

[0104] According to another aspect of the present application, an electronic device is also provided, wherein the electronic device includes one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors execute the above-mentioned method for determining the vehicle control mode.

[0105] As can be seen from the above content, the method for determining the vehicle control mode provided by the present application, by real-time acquisition of the vehicle state and combining the maximum slip rate of the wheel, intelligently selects the most appropriate control mode, effectively improving the vehicle's handling and safety. Under different driving conditions, the method can flexibly adjust the driving force and braking force to ensure that the longitudinal acceleration of the vehicle meets the driver's expectations, while avoiding excessive wheel slip, improving the stability and response speed of the vehicle under complex road conditions, and providing the driver with a safer and more comfortable driving experience. In addition, the present application determines the slip rate limit (i.e., the maximum slip rate) of each wheel and the maximum additional yaw moment that each wheel can provide, while ensuring the smoothness of intervention control as much as possible and reducing the loss of the brake disc, and through the determined control mode, maximizes the use of the additional yaw moment that the driving force can provide to control the understeering and oversteering states of the vehicle, thereby controlling the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend, thereby solving the technical problem of poor vehicle control smoothness when controlling the yaw stability of the vehicle by differential braking in the prior art.

[0106] The above-mentioned embodiments or examples disclosed in the present application are not exhaustive, but are only illustrative of some embodiments or examples, and are not intended to be specific limitations on the scope of protection disclosed in the present application. In the absence of contradiction, each step in a certain embodiment or example in the present application can be implemented as an independent example, and the steps can be combined arbitrarily. For example, the scheme after removing some steps in a certain embodiment or example can also be implemented as an independent example, and the order of the steps in a certain embodiment or example can be arbitrarily exchanged. In addition, the optional methods or optional examples in a certain embodiment or example can be combined arbitrarily; in addition, the various embodiments or examples can be combined arbitrarily, for example, some or all steps of different embodiments or examples can be combined arbitrarily, and a certain embodiment or example can be combined arbitrarily with the optional methods or optional examples of other embodiments or examples.

[0107] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0108] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0109] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0110] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0111] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0112] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly or all or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk, etc., which can store program code.

[0113] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for determining a vehicle control mode, characterized in that: include: Obtain the vehicle status of the vehicle at the target time; determining, according to a maximum slip rate of each wheel of the vehicle at the target time, a maximum additional yaw moment that each wheel can provide at the target time; The wheel whose actual slip ratio does not exceed the maximum slip ratio at the target moment is used as the target wheel; The control mode of the vehicle is determined based on the vehicle state and the maximum additional yaw torque that the target wheel can provide, wherein the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or change according to a target trend by adjusting the driving force and / or braking force of the target wheel.

2. The method for determining a vehicle control mode according to claim 1, characterized in that: Get the vehicle status at the target time, including: Acquire a throttle sensor signal and a brake sensor signal of the vehicle at the target time; The vehicle state is determined according to the throttle sensor signal and the brake sensor signal, wherein the vehicle state is any one of the following three states: The first state indicates that the accelerator and brake of the vehicle are not working at the same time; The second state indicates that the vehicle is in a state where the accelerator is in operation and the brake is not in operation; The third state indicates that the vehicle is in a state where the accelerator is not working and the brake is working.

3. The method for determining a vehicle control mode according to claim 2, characterized in that: Determining a control mode of the vehicle according to the vehicle state and the maximum additional yaw moment that can be provided by the target wheel includes: Determining, at the target time, an additional yaw moment expected by the driver for the target wheel according to the vehicle state at the target time and the driver's expected driving state of the vehicle at the target time; The control mode of the vehicle is determined according to the vehicle state, the maximum additional yaw moment that can be provided by the target wheel at the target time, and the expected additional yaw moment.

4. The method for determining a vehicle control mode according to claim 3, characterized in that: Determining a control mode of the vehicle according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, includes: When the vehicle state is the second state and the maximum additional yaw moment that can be provided by all the target wheels at the target moment is greater than or equal to the expected additional yaw moment, the driving force control mode is determined to be the control mode of the vehicle, wherein the driving force control mode is used to reduce the output torque corresponding to the target wheels on one side of the vehicle, and increase the output torque corresponding to the target wheels on the other side, so as to control the vehicle by applying driving force.

5. The method for determining a vehicle control mode according to claim 3, characterized in that: Determining a control mode of the vehicle according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, includes: When the vehicle state is the first state or the second state, and the maximum additional yaw moment that can be provided by any one of the target wheels at the target moment is less than the expected additional yaw moment, the collaborative control mode is determined as the control mode of the vehicle, wherein the collaborative control mode is used to apply driving force and braking force to the target wheels on different sides respectively to control the vehicle.

6. The method for determining a vehicle control mode according to claim 3, characterized in that: Determining a control mode of the vehicle according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, includes: When the vehicle state is any one of the first state, the second state and the third state, and the braking signal value of the vehicle is greater than a preset threshold value or the longitudinal force demand signal value of the vehicle is greater than a preset warning value, the braking force control mode is determined to be the control mode of the vehicle, wherein the braking force control mode is used to control the vehicle by applying braking force to the target wheel when there is no driving force on the target wheel.

7. The method for determining a vehicle control mode according to claim 3, characterized in that: After determining the control mode of the vehicle according to the vehicle state, the maximum additional yaw moment that the target wheel can provide at the target time, and the expected additional yaw moment, the method for determining the vehicle control mode further includes: According to the expected additional yaw moment of the target wheel and the moment arm from the wheel end to the center of mass of the target wheel, the expected driving force and / or expected braking force required by the target wheel in the determined control mode is determined.

8. The method for determining a vehicle control mode according to claim 1, characterized in that: The method for determining the vehicle control mode further includes: When it is detected that the actual slip rate of the i-th wheel of the vehicle at the target moment exceeds a slip rate threshold, the actual slip rate of the i-th wheel is reduced by adjusting the driving force or braking force applied to the i-th wheel, wherein i is a positive integer and the slip rate threshold is less than the maximum slip rate of the i-th wheel.

9. The method for determining a vehicle control mode according to claim 3, characterized in that: Adjusting the driving force and / or braking force of the target wheel through the control mode to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend includes: Determining an expected longitudinal force of the target wheel at the target time according to an expected additional yaw moment of the target wheel at the target time; Obtaining the actual longitudinal force of the target wheel at the target moment; According to the difference between the expected longitudinal force and the actual longitudinal force, the driving force and / or braking force of the target wheel is adjusted, and the longitudinal acceleration of the vehicle is controlled to remain unchanged or change according to a target trend.

10. The method for determining a vehicle control mode according to claim 9, characterized in that: According to the difference between the expected longitudinal force and the actual longitudinal force, adjusting the driving force and / or braking force of the target wheel, and controlling the longitudinal acceleration of the vehicle to remain unchanged or change according to a target trend, comprises: When it is detected that the difference between the expected longitudinal force and the actual longitudinal force is greater than a target threshold, the longitudinal acceleration of the vehicle is controlled to decrease according to a target trend by adjusting the driving force and / or braking force of the target wheel; When it is detected that the difference between the desired longitudinal force and the actual longitudinal force is less than or equal to the target threshold, the longitudinal acceleration of the vehicle is controlled to remain unchanged by adjusting the driving force and / or braking force of the target wheel.

11. A device for determining a vehicle control mode, characterized in that: include: An acquisition unit, used for acquiring the vehicle state of the vehicle at a target time; a first determining unit, configured to determine a maximum additional yaw moment that can be provided by each wheel of the vehicle at the target moment according to a maximum slip rate of each wheel of the vehicle at the target moment; A first processing unit is used to use a wheel whose actual slip rate does not exceed the maximum slip rate at the target moment as a target wheel; The second determination unit is used to determine the control mode of the vehicle according to the vehicle state and the maximum additional yaw torque that can be provided by the target wheel, wherein the control mode is used to control the longitudinal acceleration of the vehicle to remain unchanged or change according to the target trend by adjusting the driving force and / or braking force of the target wheel.

12. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein when the computer program is executed, the device where the computer-readable storage medium is located executes the method for determining the vehicle control mode according to any one of claims 1 to 10.

13. An electronic device, characterized in that: It includes one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors execute the method for determining the vehicle control mode as described in any one of claims 1 to 10.

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