A kind of drive-by-wire steering control method, device and electronic equipment

Abstract

The application discloses a kind of drive-by-wire steering control method, device and electronic equipment, it is related to intelligent automobile field.The method comprises: obtaining the steering parameter of vehicle, wherein the steering parameter is the steering transmission ratio between steering wheel and tire;According to the steering parameter of vehicle, the steering signal of steering wheel is converted into the desired steering angle of vehicle;Based on the desired steering angle, the desired wheel speed of each wheel of vehicle is calculated, and the wheel speed control is carried out to each wheel of vehicle according to the desired wheel speed of each wheel.Based on the above method, the desired wheel speed of each wheel of vehicle is realized by calculation desired steering angle, and the wheel speed of each wheel of vehicle is further adjusted according to the desired wheel speed of each wheel of vehicle, so as to realize the drive-by-wire steering based on wheel speed control, to ensure that backup steering system can realize the steering control of vehicle when main steering system fails.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the field of intelligent vehicles, and in particular to a steer-by-wire control method and device and electronic equipment. BACKGROUND

[0002] With the development of intelligent vehicle technology, the steer-by-wire system gradually replaces the traditional mechanical steering system, and the steering of the vehicle is realized by electric energy. The steer-by-wire system greatly improves the safety performance of the vehicle, so the steer-by-wire technology is an important direction for the intelligent development of vehicles. Compared with the traditional steering system, the steer-by-wire system can reduce the mechanical and hydraulic structure, further reducing the space layout restrictions between the steering system and providing a good foundation for the design of the intelligent driving cabin.

[0003] The steer-by-wire technology brings many advantages, but also has the disadvantage of no backup steering function after software failure. Once the steer-by-wire signal fails, the steer-by-wire system cannot meet the safety driving requirements. In order to solve the above problems, an electronic clutch device is usually installed in the vehicle equipped with the steer-by-wire system to ensure that the steering system can continue to provide mechanical steering capability when the software fails, realizing the steering of the vehicle.

[0004] Through the combination of the steer-by-wire system and the electronic clutch, the switching from the steer-by-wire system to the traditional steering system is realized, but the structure is relatively complex and the cost is relatively high, which is not suitable for use in intelligent vehicles. SUMMARY

[0005] The present application provides a steer-by-wire control method, device and electronic equipment. When the steer-by-wire signal fails and the main steering system cannot work normally, the backup steering system realizes the steering control of the vehicle by adjusting the wheel speed of the vehicle.

[0006] In a first aspect, the present application provides a steer-by-wire control method, which comprises:

[0007] obtaining a steering parameter of the vehicle, wherein the steering parameter is a steering transmission ratio between a steering wheel and a tire;

[0008] According to the steering parameter, the steering signal of the vehicle steering wheel is converted into a corresponding expected steering angle of the vehicle;

[0009] Based on the expected steering angle, the expected wheel speed of each wheel of the vehicle is calculated, and the wheel speed control of each wheel of the vehicle is performed according to the expected wheel speed of each wheel.

[0010] By the above method, when the main steering system fails and loses the drive-by-wire signal, the backup steering system can calculate the expected wheel speed of each wheel of the vehicle according to the expected steering angle of the vehicle, so as to realize the steering control of the vehicle when the main steering system fails, and the structure is relatively simple and does not need to increase additional mechanical structure.

[0011] In a possible design, after converting the steering signal of the steering wheel of the vehicle into the corresponding expected steering angle of the vehicle, the method further includes:

[0012] obtaining the current speed of the vehicle;

[0013] in response to the current speed being greater than a speed threshold, obtaining a tire side slip angle of the vehicle;

[0014] correcting the expected steering angle based on the tire side slip angle.

[0015] By the above method, the expected steering angle of the vehicle is adjusted in real time according to the vehicle driving data during the running of the vehicle, so as to ensure the control accuracy of the steering of the vehicle.

[0016] In a possible design, the calculating the expected wheel speed of each wheel of the vehicle includes:

[0017] obtaining the current yaw rate of the vehicle;

[0018] in response to the yaw rate being different from a theoretical yaw rate of the vehicle, adjusting a deflection angle corresponding to a target wheel;

[0019] calculating the expected wheel speed of each wheel based on the deflection angle.

[0020] By the above method, the expected wheel speed of each wheel of the vehicle under the actual working condition can be obtained by monitoring the driving condition of the vehicle and adjusting the expected wheel speed of each wheel of the vehicle in real time, so as to ensure the steering accuracy of the vehicle.

[0021] In a possible design, the steering control of each wheel of the vehicle according to the expected wheel speed of each wheel includes:

[0022] determining an inner wheel and an outer wheel when the vehicle is steering;

[0023] obtaining a first wheel speed corresponding to each outer wheel respectively;

[0024] determining a second wheel speed corresponding to each inner wheel respectively according to the expected wheel speed of each wheel and the first wheel speed;

[0025] adjust the inner wheel speed of each of the vehicle and the outer wheel speed of each of the vehicle according to the first wheel speed and the second wheel speed.

[0026] By the above method, after determining the inner wheel and the outer wheel when the vehicle is turning, the wheel speed of each wheel of the vehicle is adjusted according to the expected wheel speed of each wheel of the vehicle, so that the steer-by-wire based on the wheel speed control is realized.

[0027] In a possible design, the expected wheel speed of each wheel of the vehicle is calculated by a four-wheel wheel speed relationship formula.

[0028] The formula is: and wherein, L is the wheelbase of the vehicle, J f is the front wheel track, J r is the rear wheel track, V1 is the expected wheel speed of the left rear wheel, V2 is the expected wheel speed of the right rear wheel, V3 is the expected wheel speed of the left front wheel, V4 is the expected wheel speed of the right front wheel, and δ0 is the left wheel deflection angle.

[0029] In a second aspect, the present application provides a steer-by-wire control device, which comprises:

[0030] an acquisition module configured to acquire a steering parameter of the vehicle, wherein the steering parameter is a steering transmission ratio between a steering wheel and a tire;

[0031] a conversion module configured to convert a steering signal of the steering wheel of the vehicle into a corresponding expected steering angle of the vehicle according to the steering parameter;

[0032] a processing module configured to calculate expected wheel speeds of each wheel of the vehicle based on the expected steering angle, and to perform steering control on each wheel of the vehicle according to the expected wheel speeds.

[0033] In a possible design, the device further comprises a correction module, and the correction module is specifically configured to:

[0034] acquire a current speed of the vehicle;

[0035] in response to the current speed being greater than a speed threshold, acquire a tire side slip angle of the vehicle;

[0036] correct the expected steering angle based on the tire side slip angle.

[0037] In a possible design, the processing module is specifically configured to:

[0038] acquire a current yaw rate of the vehicle;

[0039] in response to the yaw angular velocity not being equal to the theoretical yaw angular velocity of the vehicle, adjusting a target wheel deflection angle corresponding to the target wheel;

[0040] based on the target wheel deflection angle, calculating a desired wheel speed of each wheel of the vehicle.

[0041] In a possible design, the processing module is further configured to:

[0042] determining an inner wheel and an outer wheel of the vehicle when the vehicle is turning;

[0043] obtaining a first wheel speed corresponding to each outer wheel respectively;

[0044] determining a second wheel speed corresponding to each inner wheel respectively according to the desired wheel speed of each wheel of the vehicle and the first wheel speed;

[0045] adjusting the wheel speed of each inner wheel of the vehicle and the wheel speed of each outer wheel of the vehicle according to the first wheel speed and the second wheel speed.

[0046] In a possible design, the processing module is further configured to:

[0047] calculating the desired wheel speed of each wheel of the vehicle by using a four-wheel wheel speed relationship formula;

[0048] the formula is: and wherein, L is a wheelbase of the vehicle, J f is a front wheel track, J r is a rear wheel track, V1 is a desired wheel speed of a left rear wheel, V2 is a desired wheel speed of a right rear wheel, V3 is a desired wheel speed of a left front wheel, V4 is a desired wheel speed of a right front wheel, and δ0 is a left wheel deflection angle.

[0049] In a third aspect, the present application provides an electronic device, comprising:

[0050] a memory configured to store a computer program;

[0051] a processor configured to execute the computer program stored in the memory, so as to implement the steps of the method for controlling a steer-by-wire system.

[0052] In a fourth aspect, the present application provides a computer readable storage medium, wherein the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the method for controlling a steer-by-wire system.

[0053] The technical effects of each aspect and each possible solution of the second aspect to the fourth aspect can be referred to the technical effect description of the first aspect and each possible solution of the first aspect, which will not be repeated here. Attached Figure Description

[0054] Figure 1 A flowchart of a steer-by-wire control method provided in this application embodiment;

[0055] Figure 2 This is a schematic diagram of a vehicle steering structure provided in an embodiment of this application;

[0056] Figure 3 A schematic diagram of signal conversion provided in an embodiment of this application;

[0057] Figure 4 A schematic diagram of a steer-by-wire control device provided as a real-time example of this application;

[0058] Figure 5 This is a schematic diagram of an electronic device structure provided in an embodiment of this application. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The specific operational methods in the method embodiments can also be applied to the device embodiments or system embodiments. It should be noted that in the description of this application, "multiple" is understood as "at least two". "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. A connected to B can represent: A and B directly connected, and A and B connected through C. Furthermore, in the description of this application, terms such as "first" and "second" are used only for distinguishing the purpose of description and should not be construed as indicating or implying relative importance or order.

[0060] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0061] Currently, vehicles using steer-by-wire technology typically include two steering systems. When the primary steering system fails, a backup steering system takes over, ensuring the vehicle can still steer even if the primary system malfunctions. The backup steering system currently used is generally an electronic clutch. When the primary steering system fails, the electronic clutch acts as a backup. However, the electronic clutch is essentially a variation of the traditional mechanical steering system. While it allows switching from steer-by-wire to traditional mechanical steering, its complex spatial structure and relatively high cost make it unsuitable for use in intelligent vehicles.

[0062] Based on the above problems, the embodiment of the present application provides a steer-by-wire control method. In the embodiment of the present application, first, the expected steering angle of the vehicle is obtained according to the steering parameter of the vehicle, and the expected wheel speed of each wheel of the vehicle corresponding to the expected steering angle is calculated. Further, different driving force or braking force is provided to the four wheels of the vehicle according to the expected wheel speed of each wheel of the vehicle, and then the driving of the vehicle is controlled. In addition, in the driving process of the vehicle, the expected steering angle and the expected wheel speed of the vehicle are adjusted by obtaining the driving data of the vehicle, so as to ensure the steering accuracy of the vehicle, so that the backup steering system can realize the accurate control of the steering of the vehicle when the main steering system of the vehicle fails.

[0063] Therefore, by the method provided in the embodiment of the present application, the steer-by-wire control based on the wheel speed control can be realized, so that when the main steering system of the vehicle fails, the backup steering system can realize the accurate control of the steering of the vehicle, and prevent accidents caused by the failure of the steering control of the vehicle.

[0064] The technical scheme of the present application will be further described below through specific embodiments. Referring to FIG. 1, a steer-by-wire control method provided by the present application is shown. The implementation process of the method is as follows: Figure 1

[0065] S11, obtaining the steering parameter of the vehicle;

[0066] First, in the driving process of the vehicle, when the system detects that the main steering system of the vehicle has a serious failure and cannot complete the expected steering of the driver, the backup steering system will be enabled. At this time, the backup steering system will obtain the steering parameter of the vehicle through the feel simulator. The steering parameter is the steering wheel-tire steering transmission ratio, that is, the ratio of the steering wheel steering angle to the wheel steering angle when the steering wheel is turned. For example, if the steering wheel is turned 360 degrees to cause the wheel to turn 20 degrees, the steering wheel-tire steering transmission ratio is 360 divided by 20, that is, the steering wheel-tire steering transmission ratio is 18:1.

[0067] In the above process, the higher the ratio of the steering wheel-tire steering transmission ratio, the greater the turning amplitude of the steering wheel when the wheel needs to turn to the corresponding angle, but the force required to turn the steering wheel will decrease. Conversely, the lower the ratio of the steering wheel-tire steering transmission ratio, the smaller the turning amplitude of the steering wheel when the wheel needs to turn to the corresponding angle, and the faster the response when the steering wheel is turned. Since the steering wheel-tire steering transmission ratio in various different vehicle models will be different, the steering parameter of the vehicle obtained through the feel simulator will be different for different vehicle models.

[0068] ​Further, the backup steering system also acquires the wheel speeds of the outer wheels of the vehicle when the vehicle is steering, and takes the wheel speeds of the outer wheels of the vehicle as the reference wheel speeds when the vehicle is steering, as shown in Figure 2 As shown in the figure, when the vehicle is steering to the right, the front left wheel and the rear left wheel are the outer wheels, and the front right wheel and the rear right wheel are the inner wheels. Similarly, when the vehicle is steering to the left, the front right wheel and the rear right wheel are the outer wheels, and the front left wheel and the rear left wheel are the inner wheels.

[0069] By the above method, the steering parameters of the vehicle and the wheel speeds of the outer wheels of the vehicle when the vehicle is steering can be acquired, and then the steering signal of the steering wheel can be converted into the expected steering angle of the vehicle according to the steering parameters of the vehicle.

[0070] S12, converting the steering signal of the steering wheel into the expected steering angle of the vehicle according to the steering parameters of the vehicle;

[0071] After the backup steering system acquires the steering parameters of the vehicle, when the vehicle is further steering, the steering feel simulator in the vehicle steer-by-wire system converts the steering angle of the steering wheel rotated by the driver into a steering signal according to the steering parameters of the vehicle, and converts the steering signal into the expected steering angle of the vehicle. For example, when the steering angle of the vehicle is calculated to be 10 degrees according to the steering wheel-tire steering transmission ratio of the vehicle, the steering feel simulator generates a steering signal according to the steering parameters, and converts the steering signal into the expected steering angle of the vehicle, which may be 15 degrees at this time.

[0072] In the embodiments of the present application, the expected steering angle of the vehicle is used for subsequent conversion into a control signal. Specifically, reference can be made to Figure 3 In Figure 3 , the steering feel simulator transmits the generated expected steering angle to the main controller in the vehicle steer-by-wire system. After receiving the expected steering angle, the main controller generates a control signal corresponding to the expected steering angle, and sends the control signal to the steering execution assembly in the vehicle steer-by-wire system.

[0073] In a possible application scenario, when the vehicle is running at high speed, the expected steering angle of the vehicle will be affected by the tire stiffness. The greater the tire stiffness, the smaller the side slip angle, which in turn leads to understeering, so that the actual steering angle is smaller than the expected steering angle, thereby causing errors in vehicle steering. Therefore, the expected steering angle of the vehicle needs to be corrected, and the specific correction method includes:

[0074] First, the current speed of the vehicle is acquired, wherein the current speed of the vehicle is the overall driving speed of the vehicle; and in response to the current speed being greater than a speed threshold, the tire side slip angle of the vehicle is acquired; finally, the expected steering angle is corrected based on the tire side slip angle.

[0075] In the embodiments of the present application, the tire side slip angle a f There are mainly two methods for obtaining the tire side slip angle a f The specific calculation formula of the tire side slip angle a

[0076]

[0077] In formula (1), l f is the distance from the vehicle mass center to the front wheel center; V x is the longitudinal speed at the vehicle mass center; V y is the lateral speed at the vehicle mass center; Yaw Rate is the yaw rate of the vehicle; and d0 is the left wheel deflection angle.

[0078] After obtaining the tire side slip angle a

[0079] For example, a vehicle speed threshold is preset in a high-speed working condition, for example, the vehicle speed threshold is set to 60Km / h. When the vehicle speed exceeds the preset vehicle speed threshold 60Km / h during vehicle driving, the tire stiffness will affect the steering angle. At this time, the tire side slip angle a f is calculated according to formula (1), and further, the expected steering angle in the actual working condition is calculated through formula (2).

[0080] The above formula (2) is specifically:

[0081] a f (2)

[0082] Therefore, after the tire side slip angle a f is calculated in the high-speed working condition, the expected steering angle in the high-speed working condition can be obtained, and further, the expected wheel speed of each wheel of the vehicle in the actual working condition is calculated according to the obtained expected steering angle, so as to improve the wheel speed control precision and the steering precision of the vehicle in high-speed running.

[0083] Through the above method, the tire side slip angle can be calculated, and the expected steering angle of the vehicle can be corrected in real time, so that the vehicle can have high steering precision.

[0084] S13, based on the expected steering angle, the expected wheel speed of each wheel of the vehicle is calculated, and the wheel speed control is performed on each wheel of the vehicle according to the expected wheel speed of each wheel.

[0085] After obtaining the desired steering angle of each wheel of the vehicle, further, the desired wheel speed of each wheel of the vehicle is calculated according to the desired steering angle of each wheel of the vehicle. Specifically, the relationship between the wheel speeds of the four wheels of the vehicle is determined according to the Ackerman steering model, and then the desired wheel speed of each wheel of the vehicle is calculated through the four-wheel wheel speed relationship formula and the desired steering angle, and the specific calculation formula is as follows:

[0086]

[0087]

[0088] In the formula (3) and the formula (4), L is the wheelbase of the vehicle; J f is the front wheel track; J r is the rear wheel track; V1 is the desired wheel speed of the left rear wheel; V2 is the desired wheel speed of the right rear wheel; V3 is the desired wheel speed of the left front wheel; V4 is the desired wheel speed of the right front wheel; and δ0 is the deflection angle of the left wheel.

[0089] Based on the formula (3) and the formula (4), the desired wheel speed of the left rear wheel, the desired wheel speed of the right rear wheel, the desired wheel speed of the left front wheel and the desired wheel speed of the right front wheel of the vehicle when steering can be determined. When the vehicle is steering, the radius of the running track of the outer front wheel is the largest, and the wheel speed is also the fastest. The radius of the running track of the outer rear wheel is smaller than that of the outer front wheel, and the wheel speed is also smaller than that of the outer front wheel. The turning radius of the inner rear wheel is the smallest when steering, and the wheel speed is also the slowest. The wheel speeds among the four wheels are adjusted by the differential to meet the conditions when steering. For example, the desired wheel speed of the left front wheel is calculated to be 40Km / h, the desired wheel speed of the right front wheel is calculated to be 39Km / h, the desired wheel speed of the left rear wheel is calculated to be 38Km / h, and the desired wheel speed of the right rear wheel is calculated to be 37Km / h when steering to the right, that is, the wheel speed of the outer wheel is always greater than that of the inner wheel when steering, and the wheel speed of each wheel can be adjusted to the corresponding desired wheel speed by the differential.

[0090] After determining the desired wheel speed corresponding to each wheel of the vehicle, different braking forces or driving forces are provided to the four wheels of the vehicle during steering of the vehicle, and the wheel speed of the inner wheel is adjusted to the desired wheel speed to achieve the desired steering angle based on the wheel speed of the outer wheel as the reference wheel speed, so as to achieve steering.

[0091] In a possible application scenario, whether the desired wheel speed of each wheel of the vehicle is correctly executed can be verified by the yaw rate of the vehicle. Therefore, it is necessary to detect the yaw rate of the vehicle in real time, so as to avoid the calculation and response error of the wheel speed control algorithm, and one optional implementation is as follows:

[0092] First, the current yaw rate of the vehicle is obtained, and the target wheel deflection angle is adjusted in response to the yaw rate not being equal to the theoretical yaw rate of the vehicle. Finally, the expected wheel speed of each wheel of the vehicle is calculated based on the deflection angle. Specifically:

[0093] When the yaw rate detected by the sensor is inconsistent with the theoretical calculation value of the yaw rate, the PID control method is used to adjust the wheel speed calculation input value δ0 of each wheel of the vehicle in real time, i.e., the target wheel deflection angle, which can further adjust the expected wheel speed of each wheel of the vehicle.

[0094] The above-mentioned theoretical calculation value of the yaw rate can be calculated by formula (5), and the specific formula is as follows:

[0095]

[0096] In formula (5), V1 is the left rear wheel speed; V2 is the right rear wheel speed.

[0097] Finally, based on the adjusted target wheel deflection angle, the expected wheel speed of each wheel of the vehicle is calculated. Specifically, the yaw rate sensor will collect the yaw rate of the vehicle in real time during the vehicle driving process, and compare it with the vehicle yaw rate calculated by the theoretical calculation. When the comparison result is inconsistent, the target wheel deflection angle δ0 is adjusted in real time by the PID control method. After obtaining the wheel speed calculation input value δ0 of each wheel of the vehicle under the actual working condition, the expected wheel speed of each wheel of the vehicle under the actual working condition is further calculated by formula (3) and formula (4), and the expected wheel speed of each wheel of the vehicle under the actual working condition is adjusted to ensure the control accuracy of the expected steering angle.

[0098] For example, during the driving process of the vehicle, the yaw rate sensor detects that the current yaw rate of the vehicle is 10 rad / s. At this time, by obtaining the driving data of the vehicle, the current left rear wheel speed and right rear wheel speed of the vehicle are obtained. According to formula (5), the theoretical yaw rate of the vehicle can be calculated, for example, the theoretical yaw rate calculated by formula (5) is 12 rad / s, which is not equal to the current yaw rate of the vehicle detected by the yaw rate sensor. Further, the wheel speed calculation input value δ0 of each wheel of the vehicle is adjusted, and the expected wheel speed of each wheel of the vehicle under the actual working condition is calculated by formula (3) and formula (4), and then the wheel speed of each wheel of the vehicle is adjusted.

[0099] During the driving of the vehicle, the wheel speed calculation input value δ0 is adjusted in real time by monitoring the vehicle yaw rate and using a PID control method when the value is different from the theoretical calculation value, so as to avoid the vehicle yaw rate not meeting the expectation due to the change of the wheel slip state, and the vehicle yaw rate is introduced to verify whether the expected wheel speed of each wheel of the vehicle is correctly executed, so as to ensure that the expected wheel speed of each wheel of the vehicle is accurately achieved, and the steering accuracy of the vehicle is ensured.

[0100] In the embodiment of the application, after the expected wheel speed of each wheel of the vehicle and the wheel speed of each outer wheel of the vehicle are obtained, the inner wheel and the outer wheel during the steering of the vehicle are determined, and the first wheel speed corresponding to each outer wheel is obtained. Further, the second wheel speed corresponding to each inner wheel is determined according to the expected wheel speed of each wheel and the first wheel speed. Finally, the wheel speed of each inner wheel of the vehicle and the wheel speed of each outer wheel of the vehicle are adjusted according to the first wheel speed and the second wheel speed.

[0101] Specifically, during the steering of the vehicle, the wheel speed of the outer wheel is always greater than the wheel speed of the inner wheel. For example, during the right turn, the left wheel is determined as the outer wheel, and the right wheel is determined as the inner wheel. During the steering, the turning radius of the outer wheel is greater than that of the inner wheel in the same time, so the movement distance of the outer wheel is greater than that of the inner wheel during the steering. After the inner wheel and the outer wheel during the steering are determined, different driving forces or braking forces are provided for the four wheels of the vehicle according to the expected wheel speed of each wheel of the vehicle, so that the steering control of the vehicle can be realized by ensuring that the four wheels of the vehicle achieve the expected wheel speed.

[0102] Based on the above method, when the main steering system of the vehicle fails, the backup steering system is enabled, the steering angle signal of the steering wheel is converted into the expected steering angle of the vehicle according to the steering parameter of the vehicle, the expected wheel speed for achieving the expected steering angle is calculated in real time according to the actual operating condition of the vehicle, and different driving forces or braking forces are provided for each wheel of the vehicle according to the expected wheel speed of the vehicle. The expected wheel speed of the vehicle is adjusted in real time in combination with the driving data during the operation of the vehicle, so that the wheel speed control progress during the movement of the vehicle is improved, and the steering accuracy of the vehicle is further ensured.

[0103] Based on the same inventive concept, the application also provides a steer-by-wire control device, as shown in Figure 4 The device comprises:

[0104] The acquisition module 401 is configured to acquire a steering parameter of the vehicle, wherein the steering parameter is a steering transmission ratio between the steering wheel and the tire.

[0105] The conversion module 402 is configured to convert the steering signal of the steering wheel of the vehicle into a corresponding expected steering angle of the vehicle according to the steering parameter.

[0106] The processing module 403 is configured to calculate expected wheel speeds of each wheel of the vehicle based on the expected steering angle, and control the wheel speeds of each wheel of the vehicle according to the expected wheel speeds.

[0107] In a possible design, the apparatus further includes a correction module, which is specifically configured to:

[0108] obtain a current vehicle speed of the vehicle;

[0109] obtain a tire side slip angle of the vehicle in response to the current vehicle speed being greater than a vehicle speed threshold;

[0110] correct the expected steering angle based on the tire side slip angle.

[0111] In a possible design, the processing module is specifically configured to:

[0112] obtain a current yaw rate of the vehicle;

[0113] adjust a target wheel deflection angle of the vehicle in response to the yaw rate not being equal to a theoretical yaw rate of the vehicle;

[0114] adjust the expected wheel speeds of the wheels based on the wheel deflection angle.

[0115] In a possible design, the processing module is further configured to:

[0116] determine an inner wheel and an outer wheel of the vehicle when the vehicle is steering;

[0117] obtain a first wheel speed corresponding to each outer wheel;

[0118] determine a second wheel speed corresponding to each inner wheel according to the expected wheel speeds of the wheels and the first wheel speed;

[0119] adjust the wheel speeds of each inner wheel of the vehicle and the wheel speeds of each outer wheel of the vehicle according to the first wheel speed and the second wheel speed.

[0120] In a possible design, the processing module is further configured to:

[0121] calculate the expected wheel speeds of the wheels of the vehicle by using a four-wheel wheel speed relationship formula;

[0122] The formula is as follows: and wherein, L represents a wheelbase of the vehicle, J represents a steering ratio of the vehicle, and V represents the expected wheel speed of the wheel. fis the front wheel track, J r is the rear wheel track, V1 is the expected wheel speed of the left rear wheel, V2 is the expected wheel speed of the right rear wheel, V3 is the expected wheel speed of the left front wheel, V4 is the expected wheel speed of the right front wheel, and δ0 is the left wheel deflection angle.

[0123] Based on the above-mentioned steer-by-wire control device, when the main steering system fails and loses the steer-by-wire signal, the backup steering system can calculate the expected wheel speed of each wheel of the vehicle according to the expected steering angle of the vehicle, so as to realize the steering control of the vehicle when the main steering system fails through the wheel speed adjustment of the vehicle, and the structure is relatively simple, without the need to increase additional mechanical structures.

[0124] Based on the same inventive concept, the electronic device provided in the embodiments of the present application can realize the functions of the above-mentioned steer-by-wire control method, and the electronic device comprises Figure 5 , and the electronic device comprises:

[0125] at least one processor 501 and a memory 502 connected with the at least one processor 501, and the specific connection medium between the processor 501 and the memory 502 is not limited in the embodiments of the present application, Figure 5 In the embodiments of the present application, the connection between the processor 501 and the memory 502 is taken as an example of connection through a bus 500. The bus 500 is represented by a thick line in Figure 5 , and the connection mode between other components is only schematically illustrated and is not limited. The bus 500 can be divided into an address bus, a data bus, a control bus, etc., and for the convenience of representation, Figure 5 In the embodiments of the present application, only one thick line is used to represent the bus 500, but it does not mean that there is only one bus or only one type of bus. Alternatively, the processor 501 can also be referred to as a controller, and the name is not limited.

[0126] In the embodiments of the present application, the memory 502 stores instructions executable by the at least one processor 501, and the at least one processor 501 can execute the steer-by-wire control method discussed above by executing the instructions stored in the memory 502. The processor 501 can realize the functions of various modules in the device shown in Figure 4 .

[0127] The processor 501 is the control center of the device, can connect each part of the entire control device through various interfaces and lines, and can monitor the entire device by running or executing the instructions stored in the memory 502 and calling the data stored in the memory 502, so as to realize various functions and process data of the device, thereby realizing the overall monitoring of the device.

[0128] In a possible design, the processor 501 can include one or more processing units, and the processor 501 can integrate an application processor and a modem processor, where the application processor mainly processes operating systems, user interfaces, and application programs, and the modem processor mainly processes wireless communication. It can be understood that the modem processor can also not be integrated into the processor 501. In some embodiments, the processor 501 and the memory 502 can be implemented on the same chip, and in some embodiments, they can also be respectively implemented on independent chips.

[0129] The processor 501 can be a general-purpose processor, for example, a central processing unit (CPU), a digital signal processor, an application-specific integrated circuit, a field programmable gate array, or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, and can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the steer-by-wire control method disclosed in the embodiments of the present application can be directly embodied as execution completed by a hardware processor, or executed by a combination of hardware and software modules in the processor.

[0130] The memory 502 is a non-volatile computer readable storage medium, which can be used to store non-volatile software programs, non-volatile computer executable programs, and modules. The memory 502 can include at least one type of storage medium, for example, can include a flash memory, a hard disk, a multimedia card, a card-type memory, a random access memory (RAM), a static random access memory (SRAM), a programmable read-only memory (PROM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic memory, a magnetic disk, an optical disk, and the like. The memory 502 is any other medium capable of carrying or storing desired program codes in the form of instructions or data structures and capable of being accessed by a computer, but is not limited thereto. The memory 502 in the embodiments of the present application can also be a circuit or any other device capable of realizing a storage function, used for storing program instructions and / or data.

[0131] By designing and programming the processor 501, the codes corresponding to the steer-by-wire control method introduced in the foregoing embodiments can be fixed into the chip, so that the chip can execute the codes when running Figure 1The steps of the steer-by-wire control method of the embodiment shown. How to design and program the processor 501 is known to those skilled in the art, and will not be described here.

[0132] Based on the same inventive concept, the embodiments of the present application also provide a storage medium, which stores computer instructions, and when the computer instructions run on a computer, the computer instructions make the computer execute the steer-by-wire control method discussed above.

[0133] In some possible implementation manners, various aspects of the steer-by-wire control method provided by the present application can also be implemented in the form of a program product, which includes program codes for making the control device execute the steps in the steer-by-wire control method according to various exemplary embodiments of the present application described above in the specification when the program product runs on the device.

[0134] Those skilled in the art should understand that the embodiments of the present application can be provided in the form of a method, a system, or a computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage, etc.) containing computer-usable program code.

[0135] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing apparatus to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing apparatus produce a device implemented in accordance with the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus that performs the functions specified in one or more flows and / or blocks.

[0136] These computer program instructions can also be stored in a computer-readable memory that can direct the computer or other programmable data processing apparatus to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including instruction apparatus, which implements the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus that performs the functions specified in one or more flows and / or blocks.

[0137] These computer program instructions can also be loaded into a computer or other programmable data processing devices, so that a series of operational steps are performed on the computer or other programmable data processing devices to generate computer-implemented processes, thus the instructions executed on the computer or other programmable data processing devices provide processes for implementing the functions specified in the flowchart Figure 1 one or more flows and / or blocks Figure 1 one or more blocks or steps of the functions specified in the flowchart

[0138] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application belong to the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. A steer-by-wire control method, characterized in that, The method includes: Obtain the vehicle's steering parameters, wherein the steering parameters are the steering gear ratio between the steering wheel and the tires; Based on the steering parameters, the steering signal of the vehicle steering wheel is converted into the desired steering angle corresponding to the vehicle; Based on the desired steering angle, the desired wheel speed of each wheel of the vehicle is calculated, and wheel speed control is performed on each wheel of the vehicle according to the desired wheel speed. The desired wheel speed of each wheel of the vehicle is calculated using the following formula: as well as L is the vehicle wheelbase, J f J is the front wheel track. r V1 is the rear wheel track, V2 is the expected wheel speed of the left rear wheel, V3 is the expected wheel speed of the left front wheel, V4 is the expected wheel speed of the right front wheel, and δ0 is the deflection angle of the left wheel.

2. The method as described in claim 1, characterized in that, After converting the steering signal from the vehicle's steering wheel into the desired steering angle corresponding to the vehicle, the method further includes: Obtain the current speed of the vehicle; In response to the current vehicle speed being greater than a vehicle speed threshold, the tire slip angle of the vehicle is obtained; Based on the tire slip angle, the desired steering angle is corrected.

3. The method as described in claim 1, characterized in that, The calculation of the expected wheel speed of each wheel of the vehicle includes: Obtain the current yaw rate of the vehicle; In response to the yaw rate not being equal to the theoretical yaw rate of the vehicle, the deflection angle corresponding to the target wheel is adjusted. Based on the deflection angle, the expected wheel speed of each wheel is calculated.

4. The method as described in claim 1, characterized in that, The step of controlling the steering of each wheel of the vehicle according to the desired wheel speed includes: Determine the inner and outer wheels of the vehicle when it is turning; Obtain the first wheel speed corresponding to each outer wheel; Based on the desired wheel speed of each wheel and the first wheel speed, determine the second wheel speed corresponding to each inner wheel; Adjust the wheel speeds of the inner wheels and outer wheels of the vehicle according to the first wheel speed and the second wheel speed.

5. A steer-by-wire control device, characterized in that, The device includes: An acquisition module is used to acquire the vehicle's steering parameters, wherein the steering parameters are the steering transmission ratio between the steering wheel and the tires; A conversion module is used to convert the steering signal of the vehicle steering wheel into the desired steering angle of the vehicle based on the steering parameters. The processing module is configured to calculate the desired wheel speed of each wheel of the vehicle based on the desired steering angle, and to control the wheel speed of each wheel of the vehicle according to the desired wheel speed. The desired wheel speed of each wheel of the vehicle is calculated using the following formula: as well as L is the vehicle wheelbase, J f J is the front wheel track. r V1 is the rear wheel track, V2 is the expected wheel speed of the left rear wheel, V3 is the expected wheel speed of the left front wheel, V4 is the expected wheel speed of the right front wheel, and δ0 is the deflection angle of the left wheel.

6. The apparatus as claimed in claim 5, characterized in that, The device further includes a correction module, which is specifically used for: Obtain the current speed of the vehicle; In response to the current vehicle speed being greater than a vehicle speed threshold, the tire slip angle of the vehicle is obtained; Based on the tire slip angle, the desired steering angle is corrected.

7. The apparatus as claimed in claim 5, characterized in that, The processing module is further configured to: Obtain the current yaw rate of the vehicle; In response to the fact that the current yaw rate of the vehicle is not equal to the theoretical yaw rate of the vehicle, the deflection angle of the target wheel is adjusted. Based on the deflection angle, the expected wheel speed of each wheel of the vehicle is calculated.

8. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor, when executing a computer program stored in the memory, implements the method steps of any one of claims 1-4.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method described in any one of claims 1-4.

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