Distributed electric drive electronic differential control method and device, electronic equipment and medium

Abstract

The invention relates to the field of vehicle steering control, in particular to a distributed electric drive electronic differential control method and device, electronic equipment and a medium. The distributed electric drive electronic differential control method comprises the steps that according to four-wheel reference steering angles and additional factors, four-wheel actual steering angles are determined; the additional factors comprise a road adhesion coefficient and / or a tire slip rate; determining a steering mode according to the reference vehicle speed and the preset vehicle speed; according to the actual steering angles of the four wheels, the reference vehicle speed, the steering modes, the vehicle mass center steering radius expressions in different steering modes and the steering radius expressions of the four wheels in different steering modes, the target wheel speeds of the four wheels are determined; and correcting the four-wheel speed according to the four-wheel target wheel speed and the four-wheel reference wheel speed. According to the invention, the wheel speed of four wheels can be accurately calculated and corrected, so that the actual motion trail of the vehicle is more consistent with the ideal target trail.

Description

Technical Field

[0001] The present application relates to the field of vehicle steering control, and more specifically, to a distributed electric drive electronic differential control method, device, electronic equipment and medium. Background Art

[0002] Under the dual pressures of environmental pollution and energy crisis, the development of electric vehicle technology has become one of the effective ways to solve these two problems. Distributed drive electric vehicles, as a new form of electric vehicles, can independently and accurately control the driving / braking torque of each motor, providing a hardware foundation for the vehicle to achieve handling stability control.

[0003] At present, the traditional differential has been eliminated in distributed electric drive, and an electronic differential has been introduced. However, the current electronic differential control strategy is not perfect enough, especially for distributed drive electric vehicles with four-wheel steering. The existing electronic differential control strategy only considers the front wheel steering when calculating the vehicle turning situation, which is not suitable for four-wheel steering vehicles and cannot calculate the turning target trajectory of four-wheel steering vehicles, resulting in technical difficulties in calculating the four-wheel target wheel speed and the feedback control between the four-wheel target wheel speed and the actual wheel speed, and there is a deviation between the ideal target trajectory of the vehicle and the actual motion trajectory.

[0004] In view of this, this application is hereby filed. Summary of the invention

[0005] The purpose of the present application is to provide a distributed electric drive electronic differential control method, device, electronic equipment and medium to solve the problems existing in the prior art of difficulty in calculating the four-wheel target wheel speed and feedback control between the four-wheel target wheel speed and the actual wheel speed, and the deviation between the ideal target trajectory of the vehicle and the actual motion trajectory.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions: In a first aspect, the present application provides a distributed electric drive electronic differential control method, comprising: Determining the actual steering angle of the four wheels according to the four-wheel reference steering angle and additional factors; the additional factors include road adhesion coefficient and / or tire slip rate; Determine a steering mode according to a reference vehicle speed and a preset vehicle speed; Determine the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes; The four-wheel speeds are corrected according to the four-wheel target speeds and the four-wheel reference speeds.

[0007] In some technical solutions, determining the actual steering angle of the four wheels according to the four-wheel reference steering angle and additional factors includes: Determine the four-wheel steering pre-bias angle according to the four-wheel reference steering angle and additional factors; The four-wheel actual steering angle is determined according to the four-wheel reference steering angle and the four-wheel steering pre-bias angle.

[0008] In some technical solutions, determining the four-wheel steering pre-bias angle according to the four-wheel reference steering angle and additional factors includes: Obtaining a mapping relationship between a four-wheel reference steering angle, an additional factor, and a four-wheel steering pre-bias angle; The four-wheel steering pre-bias angle is determined according to the mapping relationship, the four-wheel reference steering angle and the additional factors.

[0009] In some technical solutions, determining the steering mode according to the reference vehicle speed and the preset vehicle speed includes: When the reference vehicle speed is less than the preset vehicle speed, determining the steering mode as counter-steering; When the reference vehicle speed is greater than or equal to the preset vehicle speed, the steering mode is determined to be same-direction steering.

[0010] In some technical solutions, the vehicle center of mass turning radius expression in different steering modes is constructed based on the actual steering angle of the four wheels, the vehicle wheelbase and the distance from the vehicle center of mass to the rear axle; The expressions for the four-wheel steering radius in different steering modes are constructed based on the actual steering angles of the four wheels and the vehicle wheelbase.

[0011] In some technical solutions, the vehicle center of mass turning radius expression under different steering modes is constructed based on the actual steering angle of the four wheels, the vehicle wheelbase and the distance from the vehicle center of mass to the rear axle, including: According to the actual steering angles of the four wheels, construct the expression of the average steering angle of the front axle And the average steering angle of the rear axle is expressed as ; According to the steering mode, the average steering angle of the front axle is expressed as , the average steering angle of the rear axle and vehicle wheelbase l , respectively construct the vertical distance expression from the rear axle to the vehicle steering center l a , Expression for the lateral distance from the rear axle center to the steering center l b ; According to the vertical distance expression from the rear axle to the vehicle steering center l a , Expression for the lateral distance from the rear axle center to the steering center l b , Distance from vehicle center of mass to rear axle l r, construct the vehicle center of mass turning radius expression under different turning modes R g ; The four-wheel steering radius expressions of different steering modes are constructed according to the actual steering angles of the four wheels and the vehicle wheelbase, and include: According to the actual steering angles of the four wheels, construct the expression of the average steering angle of the front axle And the average steering angle of the rear axle is expressed as ; According to the steering mode, the average steering angle of the front axle is expressed as , the average steering angle of the rear axle and vehicle wheelbase l , construct the vertical distance expression from the rear axle to the vehicle steering center l a ; According to the vertical distance expression from the rear axle to the vehicle steering center l a , actual steering angle of four wheels, vehicle wheelbase l , construct the expression of four-wheel steering radius in different steering modes R i .

[0012] In some technical solutions, determining the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes includes: Determining the vehicle center of mass turning radius according to the actual steering angles of the four wheels, the steering mode and expressions for the vehicle center of mass turning radius under different steering modes; Determining a four-wheel steering radius according to the four-wheel actual steering angle, the steering mode and expressions of the four-wheel steering radius under different steering modes; The four-wheel target speeds are determined according to the vehicle center-of-mass turning radius, the four-wheel turning radius and the reference vehicle speed.

[0013] In a second aspect, the present application provides a distributed electric drive electronic differential control device, comprising: A four-wheel actual steering angle determination module, used to determine the four-wheel actual steering angle according to the four-wheel reference steering angle and additional factors; the additional factors include road adhesion coefficient and / or tire slip rate; A steering mode determination module, used for determining a steering mode according to a reference vehicle speed and a preset vehicle speed; A four-wheel target speed determination module is used to determine the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes; The four-wheel speed correction module is used to correct the four-wheel speeds according to the four-wheel target speeds and the four-wheel reference speeds.

[0014] In a third aspect, the present application provides an electronic device, including: at least one processor, and a memory communicatively coupled to at least one of the processors; The memory stores instructions that can be executed by at least one of the processors, and the instructions are executed by at least one of the processors so that at least one of the processors can perform the above method.

[0015] In a fourth aspect, the present application provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to enable a computer to execute the above method.

[0016] Compared with the prior art, the beneficial effects of this application are: The distributed electric drive electronic differential control method provided by the present application includes: determining the actual steering angle of the four wheels according to the four-wheel reference steering angle and additional factors; the additional factors include the road adhesion coefficient and / or the tire slip rate; determining the steering mode according to the reference vehicle speed and the preset vehicle speed; determining the four-wheel target wheel speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes; correcting the four-wheel wheel speed according to the four-wheel target wheel speed and the four-wheel reference wheel speed. This method comprehensively considers the influence of the four-wheel actual steering angle, steering mode, etc. on the four-wheel target wheel speed, and the calculated four-wheel target wheel speed is more accurate. Based on the obtained four-wheel target wheel speed and the four-wheel reference wheel speed, effective feedback control is implemented, and the four-wheel wheel speed can be accurately corrected, so that the actual motion trajectory of the vehicle is more consistent with the ideal target trajectory.

[0017] Furthermore, the present application determines the four-wheel steering pre-bias angle based on the four-wheel reference steering angle and additional factors, taking into account the influence of more practical additional factors on the vehicle steering angle. In this way, the calculation accuracy of the four-wheel target wheel speed can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a flow chart of the distributed electric drive electronic differential control method provided by the present application; Figure 2 It is a structural schematic diagram of the distributed electric drive electronic differential control device provided by the present application; Figure 3 It is a structural schematic diagram of the electronic device provided by this application. DETAILED DESCRIPTION

[0020] The following is a description of exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0021] As mentioned in the background technology, the prior art has problems such as difficulty in calculating the four-wheel target wheel speed and feedback control between the four-wheel target wheel speed and the actual wheel speed, and deviation between the ideal target trajectory of the vehicle and the actual motion trajectory. In this regard, the present application takes into account the influence of the four-wheel actual steering angle, steering mode, etc. on the four-wheel target wheel speed, and calculates the four-wheel actual steering angle and steering mode based on the input steering signal (including the four-wheel reference steering angle, additional factors, reference vehicle speed and preset vehicle speed, etc.), thereby making the calculated four-wheel target wheel speed more accurate, and finally implementing effective feedback control based on the obtained four-wheel target wheel speed and the four-wheel reference wheel speed, which can accurately correct the four-wheel wheel speed and make the actual motion trajectory of the vehicle more consistent with the ideal target trajectory. The present application is further described in detail below in conjunction with the embodiments.

[0022] Example 1 Figure 1 This is a flow chart of a distributed electric drive electronic differential control method provided in this embodiment. The method can be executed by a distributed electric drive electronic differential control device. The device can be composed of software and / or hardware and is generally integrated in an electronic device. The electronic device can be a VDC (Vehicle Dynamics Control) or an ECU (Electronic Control Unit). For ease of understanding, each step in the control method of this embodiment takes VDC as the execution subject.

[0023] like Figure 1 As shown, this embodiment provides a distributed electric drive electronic differential control method, comprising the following steps: S110. Determine the actual steering angle of the four wheels according to the four-wheel reference steering angle and additional factors; the additional factors include the road adhesion coefficient and / or the tire slip rate.

[0024] Among them, the four-wheel reference steering angle is the steering angle of the four wheels sent by the EPS (Electric Power Steering). The road adhesion coefficient refers to the adhesion ability of the tire on different road surfaces, which is equivalent to the friction coefficient. The value of the road adhesion coefficient is mainly determined by factors such as the material of the road, the condition of the road surface, and the tire structure, tread pattern, and material. The tire slip rate is the slip between the tire footprint and the road surface when the tire brakes or accelerates when driving straight. The road adhesion coefficient and tire slip rate are collected by the chassis area controller. The four-wheel actual steering angle is the steering angle of the four wheels of the vehicle during the actual steering process, which comprehensively considers the four-wheel reference steering angle and additional factors.

[0025] In an optional implementation manner, determining the actual steering angles of the four wheels according to the four-wheel reference steering angles and additional factors includes: Determine the four-wheel steering pre-bias angle according to the four-wheel reference steering angle and additional factors; The four-wheel actual steering angle is determined according to the four-wheel reference steering angle and the four-wheel steering pre-bias angle.

[0026] Among them, the four-wheel steering pre-bias angle is the lateral offset angle generated by the four wheels of the vehicle during the steering process.

[0027] This implementation first determines the four-wheel steering pre-bias angle based on the four-wheel reference steering angle and additional factors. The pre-bias angle can offset the influence of the sideslip angle generated by the wheels in actual movement. The actual four-wheel steering angle determined based on the pre-bias angle and the four-wheel reference steering angle is more accurate.

[0028] Optionally, the four-wheel steering pre-bias angle may be calculated using the following formula: 1， 2， 3， 4 ;in, is the actual steering angle on the inside of the front axle, is the reference steering angle on the inside of the front axle, 1 The front axle inner steering pre-bias angle; is the actual steering angle of the outer side of the front axle, is the reference steering angle of the outer side of the front axle, 2 It is the outer steering pre-bias angle of the front axle; is the actual steering angle on the inside of the rear axle, is the reference steering angle of the inner side of the rear axle; 3 is the rear axle inner steering pre-bias angle, is the actual steering angle of the outer side of the rear axle, is the reference steering angle of the outer side of the rear axle, 4 The inner and outer sides are related to the steering center position. The side of the vehicle close to the steering center is the inner side, and the side away from the steering center is the outer side. If the vehicle turns left, the left side is the inner side and the right side is the outer side.

[0029] In an optional implementation manner, determining the four-wheel steering pre-bias angle according to the four-wheel reference steering angle and the additional factors includes: Obtaining a mapping relationship between a four-wheel reference steering angle, an additional factor, and a four-wheel steering pre-bias angle; The four-wheel steering pre-bias angle is determined according to the mapping relationship, the four-wheel reference steering angle and the additional factors.

[0030] This implementation first obtains the mapping relationship between the four-wheel reference steering angle, the additional factor and the four-wheel steering pre-bias angle, and then determines the four-wheel steering pre-bias angle by combining the four-wheel reference steering angle and the additional factor in the mapping relationship. This method is simple and reliable.

[0031] Optionally, the mapping relationship can be determined by calibration, for example, the vehicle is subjected to a turning test under different additional factors (such as different road surfaces, different tires) and different vehicle speeds to obtain an actual slip angle, which is the pre-slip angle. Optionally, the mapping relationship can be in the form of a table or a formula (the dependent variable is the four-wheel steering pre-slip angle, and the independent variables are the four-wheel reference steering angle and the additional factors).

[0032] S120: Determine a steering mode according to a reference vehicle speed and a preset vehicle speed.

[0033] The steering modes include same-direction steering and different-direction steering. Same-direction steering means that the front and rear wheels are steering in the same direction, and different-direction steering means that the front and rear wheels are steering in different directions. The reference vehicle speed is the vehicle speed calculated based on the four-wheel reference wheel speeds. The calculation method can be any achievable one, and this embodiment does not impose any special restrictions. The preset vehicle speed is the vehicle speed used to distinguish whether the vehicle is steering in the same direction or steering in different directions, and can be set in the VDC.

[0034] In an optional implementation manner, determining the steering mode according to the reference vehicle speed and the preset vehicle speed includes: When the reference vehicle speed is less than the preset vehicle speed, determining the steering mode as counter-steering; When the reference vehicle speed is greater than or equal to the preset vehicle speed, the steering mode is determined to be same-direction steering.

[0035] In this embodiment, when the reference vehicle speed is less than the preset vehicle speed, the vehicle steering mode is the front and rear wheels turning in opposite directions, thereby reducing the turning radius. When the reference vehicle speed is greater than or equal to the preset vehicle speed, the vehicle steering mode is the front and rear wheels turning in the same direction, thereby increasing the turning radius to enhance vehicle stability.

[0036] S130, determining the four-wheel target speeds according to the four-wheel actual steering angles, the reference vehicle speed, the steering mode, vehicle center of mass steering radius expressions under different steering modes, and four-wheel steering radius expressions under different steering modes.

[0037] Among them, the vehicle center of mass turning radius expression under different steering modes is the calculation method of the vehicle center of mass turning radius under different steering modes. The four-wheel turning radius expression under different steering modes is the calculation method of the turning radius of the four wheels of the vehicle under different steering modes.

[0038] In an optional implementation, the vehicle center of mass turning radius expression in different steering modes is constructed based on the actual steering angle of the four wheels, the vehicle wheelbase and the distance from the vehicle center of mass to the rear axle; The expressions for the four-wheel steering radius in different steering modes are constructed based on the actual steering angles of the four wheels and the vehicle wheelbase.

[0039] The vehicle wheelbase is the distance between the front axle and the rear axle of the vehicle. This embodiment constructs the above two expressions according to different parameters, and when used, the required parameter values ​​are input into the corresponding expressions to obtain the relevant turning radius.

[0040] In an optional implementation manner, the vehicle center of mass turning radius expression in different steering modes is constructed based on the actual steering angle of the four wheels, the vehicle wheelbase and the distance from the vehicle center of mass to the rear axle, including: According to the actual steering angles of the four wheels, construct the expression of the average steering angle of the front axle And the average steering angle of the rear axle is expressed as ; According to the steering mode, the average steering angle of the front axle is expressed as , the average steering angle of the rear axle and vehicle wheelbase l , respectively construct the vertical distance expression from the rear axle to the vehicle steering center l a , Expression for the lateral distance from the rear axle center to the steering center l b ; According to the vertical distance expression from the rear axle to the vehicle steering center l a , Expression for the lateral distance from the rear axle center to the steering center l b , Distance from vehicle center of mass to rear axlel r , construct the vehicle center of mass turning radius expression under different turning modes R g ; The four-wheel steering radius expressions of different steering modes are constructed according to the actual steering angles of the four wheels and the vehicle wheelbase, and include: According to the actual steering angles of the four wheels, construct the expression of the average steering angle of the front axle And the average steering angle of the rear axle is expressed as ; According to the steering mode, the average steering angle of the front axle is expressed as , the average steering angle of the rear axle and vehicle wheelbase l , construct the vertical distance expression from the rear axle to the vehicle steering center l a ; According to the vertical distance expression from the rear axle to the vehicle steering center l a , actual steering angle of four wheels, vehicle wheelbase l , construct the expression of four-wheel steering radius in different steering modes R i .

[0041] This embodiment provides a more specific construction method for the vehicle center of mass turning radius expression under different steering modes and the four-wheel turning radius expression under different steering modes. Among them, the vertical distance from the rear axle to the vehicle turning center is the distance from the vehicle turning center point perpendicular to the extension line of the rear axle, and the lateral distance from the rear axle center to the turning center is the horizontal distance between the rear axle center point and the turning center point.

[0042] Alternatively, the expression for the average steering angle of the front axle is for: .

[0043] Rear axle average steering angle expression for: .

[0044] In the case of same-direction steering, , ; , , , , , R1, R2, R3, R4 represent the turning radius of the front axle inner side, front axle outer side, rear axle inner side, and rear axle outer side wheel respectively, R g Represents the turning radius of the vehicle's center of mass.

[0045] In case of opposite direction steering: , .

[0046] , , , , .

[0047] The above expression is actually optimized based on the Ackerman model. Compared with the traditional Ackerman model, it can accurately calculate the four-wheel steering angle for different steering modes to obtain a more accurate target trajectory.

[0048] In an optional implementation, determining the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes includes: Determining the vehicle center of mass turning radius according to the actual steering angles of the four wheels, the steering mode and expressions for the vehicle center of mass turning radius under different steering modes; Determining a four-wheel steering radius according to the four-wheel actual steering angle, the steering mode and expressions of the four-wheel steering radius under different steering modes; The four-wheel target speeds are determined according to the vehicle center-of-mass turning radius, the four-wheel turning radius and the reference vehicle speed.

[0049] This implementation first calculates the vehicle center of mass turning radius and the four-wheel turning radius based on specific parameter values ​​and corresponding expressions, and then further calculates the four-wheel target wheel speed in combination with the reference vehicle speed.

[0050] Optionally, the four-wheel target speed The following formula can be used for calculation: , r is the effective rolling radius of the wheel, v is the reference speed, v i is the four-wheel linear speed, i =1,2,3,4.

[0051] S140: Correct the four-wheel speeds according to the four-wheel target speeds and the four-wheel reference speeds.

[0052] The four-wheel reference wheel speed can be obtained from EPS. After obtaining the four-wheel target wheel speed, the torque of the four wheels is adjusted independently so that the four-wheel target wheel speed tends to the four-wheel reference wheel speed, thereby correcting the four-wheel speed, realizing the electronic differential function, and meeting the dynamic requirements of four-wheel steering.

[0053] Optionally, the above correction process may adopt PID control (Proportion-Integral-Differential) control.

[0054] Optionally, the torque adjustment value during the correction process may also adopt a pre-calibrated value.

[0055] The above-mentioned distributed electric drive electronic differential control method includes: determining the actual steering angle of the four wheels according to the four-wheel reference steering angle and additional factors; the additional factors include the road adhesion coefficient and / or the tire slip rate; determining the steering mode according to the reference vehicle speed and the preset vehicle speed; determining the four-wheel target wheel speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes; correcting the four-wheel wheel speed according to the four-wheel target wheel speed and the four-wheel reference wheel speed. This method comprehensively considers the influence of the four-wheel actual steering angle, steering mode, etc. on the four-wheel target wheel speed, and the calculated four-wheel target wheel speed is more accurate. Based on the obtained four-wheel target wheel speed and the four-wheel reference wheel speed, effective feedback control is implemented, and the four-wheel wheel speed can be accurately corrected, so that the actual motion trajectory of the vehicle is more consistent with the ideal target trajectory.

[0056] Furthermore, the present application determines the four-wheel steering pre-bias angle based on the four-wheel reference steering angle and additional factors, taking into account the influence of more practical additional factors on the vehicle steering angle. In this way, the calculation accuracy of the four-wheel target wheel speed can be further improved.

[0057] Example 2 like Figure 2 As shown, this embodiment provides a distributed electric drive electronic differential control device, including: A four-wheel actual steering angle determination module 201 is used to determine the four-wheel actual steering angle according to the four-wheel reference steering angle and additional factors; the additional factors include road adhesion coefficient and / or tire slip rate; A steering mode determination module 202, for determining a steering mode according to a reference vehicle speed and a preset vehicle speed; A four-wheel target speed determination module 203 is used to determine the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes; The four-wheel speed correction module 204 is used to correct the four-wheel speeds according to the four-wheel target speeds and the four-wheel reference speeds.

[0058] The device is used to execute the above method, and thus has at least functional modules and beneficial effects corresponding to the above method.

[0059] Example 3 like Figure 3 As shown, this embodiment provides an electronic device, including: at least one processor; and a memory communicatively connected to at least one of the processors; wherein, The memory stores instructions executable by at least one of the processors, and the instructions are executed by at least one of the processors to enable at least one of the processors to perform the above method. At least one processor in the electronic device can perform the above method, and thus has at least the same advantages as the above method.

[0060] Optionally, the electronic device also includes interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. The various components are connected to each other using different buses and can be installed on a common mainboard or installed in other ways as needed. The processor can process instructions executed in the electronic device, including instructions stored in or on a memory to display graphical information of a GUI (Graphical User Interface) on an external input / output device (such as a display device coupled to an interface). In other embodiments, if necessary, multiple processors can be used together with multiple memories, and / or multiple buses can be used together with multiple memories. Similarly, multiple electronic devices can be connected (for example, as a server array, a group of blade servers, or a multi-processor system), and each device provides some necessary operations. Figure 3 A processor 301 is taken as an example.

[0061] The memory 302, as a computer-readable storage medium, can be used to store software programs, computer executable programs and modules, such as the program instructions / modules corresponding to the distributed electric drive electronic differential control method in the embodiment of the present application (for example, the four-wheel actual steering angle determination module, the steering mode determination module, the four-wheel target wheel speed determination module, and the four-wheel wheel speed correction module in the distributed electric drive electronic differential control device). The processor 301 executes various functional applications and data processing of the device by running the software programs, instructions and modules stored in the memory 302, that is, realizing the above-mentioned distributed electric drive electronic differential control method.

[0062] The memory 302 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system and at least one application required for a function; the data storage area may store data created according to the use of the terminal, etc. In addition, the memory 302 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some instances, the memory 302 may further include a memory remotely arranged relative to the processor 301, and these remote memories may be connected to the device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0063] The electronic device may further include: an input device 303 and an output device 304. The processor 301, the memory 302, the input device 303 and the output device 304 may be connected via a bus or other means. Figure 3 The example of connecting through bus is taken in the following.

[0064] The input device 303 can receive input digital or character information, and the output device 304 can include a display device, an auxiliary lighting device (e.g., LED), and a tactile feedback device (e.g., a vibration motor), etc. The display device can include, but is not limited to, a liquid crystal display (LCD), a light emitting diode (LED) display, and a plasma display. In some embodiments, the display device can be a touch screen.

[0065] Example 4 This embodiment provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to enable a computer to execute the above method. The computer instructions on the computer-readable storage medium are used to enable a computer to execute the above method, and thus have at least the same advantages as the above method.

[0066] The medium in this application may adopt any combination of one or more computer-readable media. The medium may be a computer-readable signal medium or a computer-readable storage medium. The medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination thereof. More specific examples of the medium (a non-exhaustive list) include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this document, the medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, device, or device.

[0067] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0068] The program code contained on the computer-readable medium can be transmitted using any appropriate medium, including but not limited to wireless, wire, optical cable, RF (Radio Frequency), etc., or any suitable combination of the above.

[0069] Computer program code for performing the operation of the present application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages, such as Java, Smalltalk, C++, and conventional procedural programming languages, such as "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (e.g., using an Internet service provider to connect through the Internet).

[0070] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this application can be executed in parallel, sequentially or in different orders, as long as the expected results of the technical solution disclosed in this application can be achieved, and this document is not limited here.

[0071] The above specific implementations do not constitute a limitation on the protection scope of this application. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included in the protection scope of this application.

Claims

1. A distributed electric drive electronic differential control method, characterized in that: include: Determine the actual steering angle of the four wheels according to the four-wheel reference steering angle and additional factors; The additional factors include road adhesion coefficient and / or tire slip rate; Determine a steering mode according to a reference vehicle speed and a preset vehicle speed; Determine the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes; The four-wheel speeds are corrected according to the four-wheel target speeds and the four-wheel reference speeds.

2. The distributed electric drive electronic differential control method according to claim 1, characterized in that: Determining the actual steering angles of the four wheels according to the four-wheel reference steering angles and additional factors includes: Determine the four-wheel steering pre-bias angle according to the four-wheel reference steering angle and additional factors; The four-wheel actual steering angle is determined according to the four-wheel reference steering angle and the four-wheel steering pre-bias angle.

3. The distributed electric drive electronic differential control method according to claim 2, characterized in that: Determining the four-wheel steering pre-bias angle according to the four-wheel reference steering angle and the additional factors includes: Obtaining a mapping relationship between a four-wheel reference steering angle, an additional factor, and a four-wheel steering pre-bias angle; The four-wheel steering pre-bias angle is determined according to the mapping relationship, the four-wheel reference steering angle and the additional factors.

4. The distributed electric drive electronic differential control method according to claim 1, characterized in that: The step of determining the steering mode according to the reference vehicle speed and the preset vehicle speed includes: When the reference vehicle speed is less than the preset vehicle speed, determining the steering mode as counter-steering; When the reference vehicle speed is greater than or equal to the preset vehicle speed, the steering mode is determined to be same-direction steering.

5. The distributed electric drive electronic differential control method according to claim 1, characterized in that: The vehicle center of mass turning radius expression in different steering modes is constructed based on the actual steering angle of the four wheels, the vehicle wheelbase and the distance from the vehicle center of mass to the rear axle; The expressions for the four-wheel steering radius in different steering modes are constructed based on the actual steering angles of the four wheels and the vehicle wheelbase.

6. The distributed electric drive electronic differential control method according to claim 5, characterized in that: The vehicle center of mass turning radius expressions under different steering modes are constructed based on the actual steering angles of the four wheels, the vehicle wheelbase, and the distance from the vehicle center of mass to the rear axle, and include: According to the actual steering angles of the four wheels, construct the expression of the average steering angle of the front axle And the average steering angle of the rear axle is expressed as ; According to the steering mode, the average steering angle of the front axle is expressed as , the average steering angle of the rear axle and vehicle wheelbase l , respectively construct the vertical distance expression from the rear axle to the vehicle steering center l a , Expression for the lateral distance from the rear axle center to the steering center l b ; According to the vertical distance expression from the rear axle to the vehicle steering center l a , Expression for the lateral distance from the rear axle center to the steering center l b , Distance from vehicle center of mass to rear axle l r , construct the vehicle center of mass turning radius expression under different turning modes R g ; The four-wheel steering radius expressions of different steering modes are constructed according to the actual steering angles of the four wheels and the vehicle wheelbase, and include: According to the actual steering angles of the four wheels, construct the expression of the average steering angle of the front axle And the average steering angle of the rear axle is expressed as ; According to the steering mode, the average steering angle of the front axle is expressed as , the average steering angle of the rear axle and vehicle wheelbase l , construct the vertical distance expression from the rear axle to the vehicle steering center l a ; According to the vertical distance expression from the rear axle to the vehicle steering center l a , actual steering angle of four wheels, vehicle wheelbase l , construct the expression of four-wheel steering radius in different steering modes R i .

7. The distributed electric drive electronic differential control method according to claim 1, characterized in that: Determining the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes includes: Determining the vehicle center of mass turning radius according to the actual steering angles of the four wheels, the steering mode and expressions for the vehicle center of mass turning radius under different steering modes; Determining a four-wheel steering radius according to the four-wheel actual steering angle, the steering mode and expressions of the four-wheel steering radius under different steering modes; The four-wheel target speeds are determined according to the vehicle center-of-mass turning radius, the four-wheel turning radius and the reference vehicle speed.

8. A distributed electric drive electronic differential control device, characterized in that: include: A four-wheel actual steering angle determination module, used to determine the four-wheel actual steering angle according to the four-wheel reference steering angle and additional factors; The additional factors include road adhesion coefficient and / or tire slip rate; A steering mode determination module, used for determining a steering mode according to a reference vehicle speed and a preset vehicle speed; A four-wheel target speed determination module is used to determine the four-wheel target speed according to the four-wheel actual steering angle, the reference vehicle speed, the steering mode, the vehicle center of mass steering radius expression under different steering modes, and the four-wheel steering radius expression under different steering modes; The four-wheel speed correction module is used to correct the four-wheel speeds according to the four-wheel target speeds and the four-wheel reference speeds.

9. An electronic device, characterized in that: include: at least one processor, and a memory communicatively coupled to at least one of the processors; The memory stores instructions executable by at least one of the processors, and the instructions are executed by at least one of the processors so that the at least one processor can execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method according to any one of claims 1 to 7.

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