Electric steering control method and system suitable for different working conditions

Abstract

The invention discloses an electric steering control method and system suitable for different working conditions, and the method comprises the steps: obtaining a pavement roughness evaluation value when a vehicle runs on a pavement; obtaining a steering damping gain, a steering power-assisted gain and a steering return gain; according to the road surface roughness evaluation quantity, the steering damping gain, the steering power-assisted gain, the steering return gain and the tire pressure information, system output current is obtained through calculation; the invention relates to the technical field of vehicle control, is suitable for an automobile applying an electric power steering system, and is used for calculating steering power-assisted output through wheel acceleration, automobile body height, steering torque, turning angle, automobile speed, a camera and tire pressure so as to improve the operation stability of the automobile.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and particularly relates to an electric steering control method and system applicable to different working conditions. Background Art

[0002] During the development process of an electric power steering system, its steering assistance parameters are generally determined on a road surface under standard tire pressure and test conditions. However, in actual usage conditions, the tire pressure may have a large error relative to the standard tire pressure, and the road surface conditions are quite different from those used during the development process, resulting in a relatively large difference in vehicle performance compared to the development process. The handling stability performance of the user during actual driving may be relatively poor and the performance is not stable enough.

[0003] The existing technical solutions generally are to prepare multiple steering assistance parameters in advance for different road surface and tire pressure states, and switch the steering assistance parameters when the usage conditions change to make it adapt to the current working conditions. The above solutions have the following problems: The switching between several assistance parameters is not a continuous process, so torque fluctuations are likely to occur during the switching of assistance parameters, and the working conditions it can adapt to are limited, and it can only adapt to fixed two or several working conditions. Summary of the Invention

[0004] The purpose of the present invention is to provide an electric steering control method and system applicable to different working conditions to solve the problems proposed in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: An electric steering control method applicable to different working conditions, including:

[0006] Obtaining an evaluation quantity of road surface roughness when the vehicle is driving on the road surface;

[0007] Obtaining a steering damping gain, a steering assistance gain, and a steering return gain;

[0008] Calculating and obtaining a system output current according to the evaluation quantity of road surface roughness, the steering damping gain, the steering assistance gain, the steering return gain, and the tire pressure information.

[0009] Further, obtaining the evaluation quantity of road surface roughness when the vehicle is driving on the road surface further includes:

[0010] Collecting road surface image information, evaluating the road surface roughness according to the road surface image information, and obtaining an initial road surface roughness evaluation value;

[0011] Further, obtaining a fused calculation of the wheel acceleration, the vehicle body height, and the initial road surface roughness evaluation value to obtain the evaluation quantity of road surface roughness.

[0012] Further, the calculation formula of the evaluation quantity of road surface roughness:

[0013] P L = K L g L (a z , B h , R rc ) —— Equation (1);

[0014] Wherein, P L is the road surface roughness evaluation quantity, K L is the road surface roughness evaluation quantity gain, a z is the wheel acceleration, B h is the vehicle body height, R rc is the preliminary road surface roughness evaluation value.

[0015] Furthermore, obtaining the steering damping gain, the steering assist gain, and the steering return gain further includes:

[0016] When the vehicle is running, obtain the steering torque, the vehicle running speed, and the steering angle;

[0017] Calculate and obtain the steering damping gain and the steering return gain respectively according to the steering torque, the vehicle running speed, and the steering angle, and calculate and obtain the steering assist gain according to the steering torque and the vehicle running speed.

[0018] Furthermore, the steering damping gain calculation formula:

[0019] P f = K f0 g f (T, A, V) —— Equation (2);

[0020] The steering return gain calculation formula:

[0021] P a = K a0 g a (T, V) —— Equation (3);

[0022] The steering assist gain calculation formula:

[0023] P r = K r0 g r (T, A, V) —— Equation (4);

[0024] In the formula, P f is the steering damping gain, P a is the steering assist gain, P r is the steering return gain, K f0 , K a0 , K r0 are their gain constants respectively, T is the steering torque, V is the vehicle speed, and A is the steering angle.

[0025] Further, according to the road surface roughness evaluation quantity, steering damping gain, steering assist gain, steering return gain, and tire pressure information, a system output current is calculated, and the system output current calculation formula is further included:

[0026]

[0027] In the formula, K is the tire pressure gain, r0 is the vehicle standard tire pressure, and r i is the current vehicle tire pressure.

[0028] On the other hand, an electric power steering control system applicable to different working conditions is provided, and an electric power steering control method applicable to different working conditions described in any one of the above is applied, including:

[0029] A first acquisition module for obtaining the road surface roughness evaluation quantity when the vehicle is driving on the road surface;

[0030] A second acquisition module for acquiring the steering damping gain, steering assist gain, and steering return gain;

[0031] A calculation module for calculating a system output current according to the road surface roughness evaluation quantity, steering damping gain, steering assist gain, steering return gain, and tire pressure information.

[0032] On still another aspect, an electronic device is provided, and the electronic device includes:

[0033] One or more processors;

[0034] A storage device for storing one or more programs,

[0035] When the one or more programs are executed by the one or more processors, the one or more processors implement an electric power steering control method applicable to different working conditions as described in any one of the above.

[0036] Another computer-readable storage medium, on which a computer program is stored, characterized in that when the program is executed by a processor, an electric power steering control method applicable to different working conditions as described in any one of the above is implemented.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention relates to the technical field of vehicle steering control and is applicable to automobiles using an electric power steering system. To solve the above problems, the present invention provides an electric power steering control method and system applicable to different working conditions. The specific solution is to calculate the steering assist output through wheel acceleration, vehicle body height, steering torque, steering angle, vehicle speed, camera, and tire pressure, thereby improving the handling stability of the vehicle. Description of the Drawings

[0038] Figure 1 It is a flowchart of an electric power steering control method applicable to different working conditions in an embodiment of the present invention;

[0039] Figure 2 It is a connection block diagram of an electric power steering control system applicable to different working conditions in an embodiment of the present invention;

[0040] Figure 3 It is a schematic connection diagram of an electronic device and a computer-readable storage medium structure in an embodiment of the present invention;

[0041] In the figure: 10, memory; 11, processor; 12, communication bus; 13, communication interface; 14, computer program; 15, storage medium; 16, first acquisition module; 17, second acquisition module; 18, calculation module. Detailed implementation manners

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0043] In the description of the present invention, unless otherwise specified, "a plurality of" means two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "connected" and "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0045] Please refer to the accompanying drawings of the specification. The present invention provides a technical solution: an electric power steering control method applicable to different working conditions, including the following steps:

[0046] S102. Obtain the road surface roughness evaluation quantity when the vehicle is driving on the road surface;

[0047] Specifically, collect road surface image information, and evaluate the road surface roughness according to the road surface image information to obtain the initial road surface roughness evaluation value;

[0048] Among them, in this embodiment, the road surface image information is collected by the image acquisition module, and the road surface roughness is evaluated according to the road surface image information to obtain the initial road surface roughness evaluation value.

[0049] Specifically, obtain the wheel acceleration, body height, and calculate the road surface roughness evaluation quantity by fusing the initial road surface roughness evaluation value.

[0050] Specifically, the calculation formula of the road surface roughness evaluation quantity:

[0051] P L =K L g L (a z ,B h ,R rc )——Formula (1);

[0052] In the formula, P L is the road surface roughness evaluation quantity, K L is the road surface roughness evaluation quantity gain, a z is the wheel acceleration, B h is the body height, R rc is the preliminary road surface roughness evaluation value.

[0053] Among them, g L (a z ,B h ,R rc ) is a function related to the wheel acceleration, body height, and the preliminary road surface roughness evaluation value.

[0054] S104. Obtain the steering damping gain, steering assist gain, and steering return gain;

[0055] Specifically, when the vehicle is driving, obtain the steering torque, vehicle driving speed, and steering angle;

[0056] Calculate the steering damping gain and steering return gain respectively according to the steering torque, vehicle driving speed, and steering angle, and calculate the steering assist gain according to the steering torque and vehicle driving speed.

[0057] Specifically, the calculation formula of the steering damping gain:

[0058] P f =K f0 g f(T, A, V) —— Equation (2);

[0059] Steering return gain calculation formula:

[0060] P a = K a0 g a (T, V) —— Equation (3);

[0061] Steering assist gain calculation formula:

[0062] P r = K r0 g r (T, A, V) —— Equation (4);

[0063] In the formula, P f is the steering damping gain, P a is the steering assist gain, P r is the steering return gain, K f0 , K a0 , K r0 are their gain constants respectively, T is the steering torque, V is the vehicle speed, and A is the steering angle.

[0064] Among them, g f (T, A, V) and g r (T, A, V) are both functions related to the steering torque, vehicle speed, and steering angle; g a (T, V) is a function related to the steering torque and vehicle speed.

[0065] S106. Calculate the system output current based on the road surface roughness evaluation value, steering damping gain, steering assist gain, steering return gain, and tire pressure information.

[0066] Specifically, the system output current calculation formula:

[0067]

[0068] In the formula, K is the tire pressure gain, r0 is the vehicle standard tire pressure, and r i is the current vehicle tire pressure.

[0069] On the other hand, an electric power steering control system applicable to different working conditions is provided. Applying the electric power steering control method applicable to different working conditions described in any one of the above, it is characterized by including:

[0070] The first acquisition module 16 is used to obtain the road surface roughness evaluation value when the vehicle is driving on the road surface;

[0071] Among them, road surface image information is collected, and based on the road surface image information, the road surface roughness is evaluated to obtain an initial road surface roughness evaluation value. In this embodiment, it is preferably to collect road surface image information through a camera module.

[0072] The wheel acceleration, vehicle body height, and the initial road surface roughness evaluation value are obtained and fused to calculate the road surface roughness evaluation quantity.

[0073] Formula for calculating the road surface roughness evaluation quantity:

[0074] P L =K L g L (a z ,B h ,R rc ) —— Formula (1);

[0075] Among them, P L is the road surface roughness evaluation quantity, K L is the road surface roughness evaluation quantity gain, a z is the wheel acceleration, B h is the vehicle body height, R rc is the preliminary road surface roughness evaluation value.

[0076] Among them, in this embodiment, the wheel acceleration information is obtained through an acceleration sensor; the vehicle body height information is obtained through a height sensor.

[0077] The second acquisition module 17 is used to acquire the steering damping gain, steering assist gain, and steering return gain;

[0078] Among them, acquiring the steering damping gain, steering assist gain, and steering return gain further includes:

[0079] When the vehicle is running, acquire the steering torque, vehicle running speed, and steering angle;

[0080] The steering damping gain and steering return gain are respectively calculated based on the steering torque, vehicle running speed, and steering angle, and the steering assist gain is calculated based on the steering torque and vehicle running speed.

[0081] In this embodiment, the steering torque sensor acquires the steering torque information of the steering system; the vehicle speed acquisition module acquires the vehicle speed information; the steering angle sensor acquires the steering angle information of the steering system.

[0082] Formula for calculating the steering damping gain:

[0083] P f =K f0 g f (T,A,V) —— Formula (2);

[0084] Steering return gain calculation formula:

[0085] P a = K a0 g a (T, V) —— Formula (3);

[0086] Steering assist gain calculation formula:

[0087] P r = K r0 g r (T, A, V) —— Formula (4);

[0088] Wherein, P f is the steering damping gain, P a is the steering assist gain, P r is the steering return gain, K f0 , K a0 , K r0 are their gain constants respectively, T is the steering torque, V is the vehicle speed, and A is the steering angle.

[0089] The calculation module 18 is configured to calculate and obtain the system output current according to the road surface roughness evaluation quantity, the steering damping gain, the steering assist gain, the steering return gain, and the tire pressure information.

[0090] In this embodiment, a tire pressure sensor is used to obtain the vehicle tire pressure information; a damping control module is set to calculate the damping control output current; a steering assist control module is set to calculate the steering assist control output current; a return control module is set to calculate the steering return control output current; a assist correction module is set to calculate the system final output current.

[0091] Wherein, the system output current calculation formula:

[0092]

[0093] Wherein, K is the tire pressure gain, r0 is the vehicle standard tire pressure, and r i is the current vehicle tire pressure.

[0094] On the other hand, as Figure 3 shown, an electronic device is provided, and the electronic device includes:

[0095] One or more processors 11;

[0096] A storage device for storing one or more programs,

[0097] When the one or more programs are executed by the one or more processors 11, the one or more processors 11 implement an electric steering control method applicable to different working conditions as described in any of the above.

[0098] Specifically, the storage device is a memory 10, a processor (CPU) 11, and a computer program 14. The computer program 14 is stored in the memory 10, and the processor 11 executes the computer program 14 to implement an electric power steering control method applicable to different working conditions described in any one of the above. The control system further includes: a communication interface 13 and a communication bus 12. The processor 11, the communication interface 13, and the memory 10 communicate through the communication bus 12, where the communication bus 12 is an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The bus can be divided into an address bus, a data bus, a control bus, etc. If the memory 10, the processor 11, and the communication interface 13 are integrated on a single chip, the memory 10, the processor 11, and the communication interface 13 can communicate with each other through an internal interface.

[0099] The processor 11 can also be a specific integrated circuit or multiple integrated circuits.

[0100] In another aspect, as Figure 3 shown, a computer-readable storage medium 15 is provided, on which a computer program 14 is stored. When the program is executed by the processor 11, it implements an electric power steering control method applicable to different working conditions described in any one of the above.

[0101] Specifically, the computer program 14 may include program code, and the program code includes computer operation instructions; the memory 10 is used to store the computer program 14. The memory 10 may include a high-speed RAM memory and may also include non-volatile memory, such as at least one disk memory; the communication interface 13 is used to communicate with other devices, such as network elements of a client or other servers.

[0102] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An electric power steering control method applicable to different working conditions, characterized in that, Including: Obtaining a road surface roughness evaluation quantity when the vehicle is driving on the road surface; Obtaining a steering damping gain, a steering assist gain, and a steering return gain; Calculating and obtaining a system output current according to the road surface roughness evaluation quantity, the steering damping gain, the steering assist gain, the steering return gain, and the tire pressure information.

2. The electric power steering control method applicable to different working conditions according to claim 1, characterized in that, Obtaining a road surface roughness evaluation quantity when the vehicle is driving on the road surface further includes: Collecting road surface image information, evaluating the road surface roughness according to the road surface image information, and obtaining an initial road surface roughness evaluation value.

3. A method for controlling an electric power steering applicable to different working conditions according to claim 2, characterized in that, Including: Obtaining a road surface roughness evaluation quantity by fusing and calculating the wheel acceleration, the vehicle body height, and the initial road surface roughness evaluation value.

4. A method for electric power steering control applicable to different working conditions according to claim 3, characterized in that, Road surface roughness evaluation quantity calculation formula: P L = K L g L (a z , B h , R rc ) —— Formula (1); Among them, P L is the pavement roughness evaluation quantity, K L is the pavement roughness evaluation quantity gain, a z is the wheel acceleration, B h is the vehicle body height, R rc is the preliminary pavement roughness evaluation value.

5. A method for electric power steering control applicable to different working conditions according to claim 1, characterized in that, Obtaining a steering damping gain, a steering assist gain, and a steering return gain further includes: When the vehicle is driving, obtaining the steering torque, the vehicle driving speed, and the steering angle; Calculating and obtaining the steering damping gain and the steering return gain respectively according to the steering torque, the vehicle driving speed, and the steering angle, and calculating and obtaining the steering assist gain according to the steering torque and the vehicle driving speed.

6. The electric steering control method applicable to different working conditions according to claim 5, characterized in that, Including: Steering damping gain calculation formula: P f = K f0 g f (T, A, V) —— Equation (2); Steering return gain calculation formula: P a = K a0 g a (T, V) —— Equation (3); Steering assist gain calculation formula: P r = K r0 g r (T, A, V) —— Equation (4); Wherein, P f is the steering damping gain, P a is the steering assist gain, P r is the steering return gain, K f0 , K a0 , K r0 are their gain constants respectively, T is the steering torque, V is the vehicle speed, and A is the steering angle.

7. A method for electric power steering control applicable to different working conditions according to claim 1, characterized in that, Calculating and obtaining a system output current according to the road surface roughness evaluation quantity, the steering damping gain, the steering assist gain, the steering return gain, and the tire pressure information further includes a system output current calculation formula: Where K is the tire pressure gain, r0 is the standard tire pressure of the vehicle, and r i is the current tire pressure of the vehicle.

8. An electric power steering control system applicable to different working conditions, applying the electric power steering control method applicable to different working conditions according to any one of claims 1 to 7, characterized in that, Including: A first obtaining module, configured to obtain a road surface roughness evaluation quantity when the vehicle is driving on the road surface; A second obtaining module, configured to obtain a steering damping gain, a steering assist gain, and a steering return gain; A calculation module, configured to calculate and obtain a system output current according to the road surface roughness evaluation quantity, the steering damping gain, the steering assist gain, the steering return gain, and the tire pressure information.

9. An electronic device, characterized in that, The electronic device includes: One or more processors; A storage device, configured to store one or more programs, When the one or more programs are executed by the one or more processors, enabling the one or more processors to implement an electric steering control method applicable to different working conditions as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements an electric steering control method applicable to different working conditions as described in any one of claims 1 to 7.

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