CN118289086B

CN118289086B - Drive-by-wire steering variable transmission ratio control method, control system and vehicle

Info

Publication number: CN118289086B
Application number: CN202410716575.7A
Authority: CN
Inventors: 王德平; 高尚; 赵慧超; 侯杰; 禹真; 常秀岩; 曹龙; 何畅; 李春善; 张鸿
Original assignee: FAW Group Corp
Current assignee: FAW Group Corp
Priority date: 2024-06-04
Filing date: 2024-06-04
Publication date: 2024-08-30
Anticipated expiration: 2044-06-04
Also published as: CN118289086A

Abstract

The invention discloses a control method, a control system and a vehicle for a drive-by-wire steering variable transmission ratio, and belongs to the technical field of vehicles, wherein the control method for the drive-by-wire steering variable transmission ratio inputs acquired state information of the vehicle into a redundancy check control algorithm for redundancy processing, and provides high-safety redundancy control information so as to improve safety; and the redundant control information is output to obtain driving mode cyclic check output and vehicle speed information cyclic check output, then the content of the check output is subjected to variable transmission ratio decision calculation, the decided variable transmission ratio is used as external output to perform variable transmission ratio control, the variable transmission ratio function of steer-by-wire is realized, and the problem of vehicle stability caused by variable transmission ratio output under the conditions of different driving modes switching and different vehicle speeds of a steer-by-wire control system is solved by designing a steer-by-wire variable transmission ratio control strategy for improving the vehicle stability, so that the potential vehicle instability risk is avoided.

Description

Drive-by-wire steering variable transmission ratio control method, control system and vehicle

Technical Field

The invention relates to the technical field of vehicles, in particular to a drive-by-wire steering gear ratio control method, a control system and a vehicle thereof.

Background

For the steer-by-wire system, as the mechanical connection of the intermediate shaft is canceled between the road feel simulator and the steer-by-wire actuator, the steer-by-wire system can perform variable transmission ratio control, and the variable transmission ratio control can provide different vehicle corner outputs through different driver inputs under different driving modes, different vehicle speeds and the like. However, the current variable transmission ratio decision algorithm has the problem of common pain points, and under the condition of switching driving modes and obviously changing the vehicle speed, the steering angle of the variable transmission ratio output at the moment has deviation, so that a driver can feel obvious phenomena of vehicle instability, excessive steering, insufficient steering and the like, and the risk of vehicle instability exists.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the invention provides the drive-by-wire steering gear ratio control method, which can effectively avoid potential vehicle instability risks and improve the user driving experience of the drive-by-wire steering control system.

The invention further provides a steering-by-wire control system, a vehicle controller and a vehicle comprising the steering-by-wire control system.

According to the first aspect of the embodiment of the invention, the drive-by-wire steering ratio control method comprises the following steps:

Acquiring state information of a vehicle, and inputting the state information into a redundancy check control algorithm to perform redundancy processing to obtain redundancy control information;

Performing output processing according to the redundant control information to obtain driving mode cyclic check output and vehicle speed information cyclic check output;

performing variable transmission ratio decision calculation according to the driving mode cyclic check output and the vehicle speed information cyclic check output to obtain a decided variable transmission ratio;

And controlling the variable transmission ratio of the linear steering system by using the decided variable transmission ratio.

The drive-by-wire steering ratio-changing control method provided by the embodiment of the invention has at least the following beneficial effects:

The acquired state information of the vehicle is input into a redundancy check control algorithm to carry out redundancy processing, and high-safety redundancy control information is provided to improve safety; and the redundant control information is output to obtain driving mode cyclic check output and vehicle speed information cyclic check output, then the content of the check output is subjected to variable transmission ratio decision calculation, the decided variable transmission ratio is used as external output to perform variable transmission ratio control, the variable transmission ratio function of steer-by-wire is realized, and the steering-by-wire variable transmission ratio control strategy for improving the stability of the vehicle is designed, so that the problem of vehicle stability caused by variable transmission ratio output under the conditions of switching different driving modes and changing different vehicle speeds of a steering-by-wire control system is solved, the potential risk of instability of the vehicle is avoided, and the driving experience of a user is improved.

According to some embodiments of the present invention, the state information includes a driving mode, a driving mode switching request, and a steering wheel angle, and the performing output processing according to the redundant control information to obtain a driving mode cycle check output and a vehicle speed information cycle check output includes:

determining a current driving mode of the vehicle according to the driving mode;

when the driving mode switching request is received, judging whether the current steering wheel angle is in a first preset range or not by using a driving mode cycle checking algorithm;

Executing switching of a driving mode of the vehicle when the steering wheel angle is within the first preset range;

and when the steering wheel angle exceeds the first preset range, maintaining the current driving mode of the vehicle.

According to some embodiments of the present invention, the state information includes a vehicle speed and a steering wheel angle, and the outputting according to the redundant control information to obtain a driving mode cycle check output and a vehicle speed information cycle check output includes:

acquiring the current vehicle speed;

When a control command of the vehicle speed is received, judging whether the current steering wheel angle is in a second preset range or not by utilizing a vehicle speed circulation checking algorithm;

When the steering wheel angle is within the second preset range, updating the vehicle speed;

And when the steering wheel angle exceeds the second preset range, maintaining the current vehicle speed.

According to some embodiments of the invention, when the steering wheel angle is within the second preset range, after updating the vehicle speed, the method further includes:

acquiring the updated vehicle speed and the vehicle speed at the previous moment, and comparing the updated vehicle speed with the vehicle speed at the previous moment;

and continuously executing updating of the vehicle speed when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the last moment is in a third preset range.

And when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the last moment exceeds the third preset range, controlling the current vehicle speed according to a vehicle speed following algorithm so as to control the variation range of the vehicle speed.

According to some embodiments of the invention, the state information includes steering wheel angle, the driving mode cyclic check output includes a driving mode processed by a driving mode cyclic check algorithm, and the vehicle speed information cyclic check output includes a vehicle speed processed by a vehicle speed cyclic check algorithm;

And performing variable transmission ratio decision calculation according to the driving mode cyclic check output and the vehicle speed information cyclic check output to obtain a decided variable transmission ratio, wherein the method comprises the following steps of:

And taking the driving mode, the vehicle speed and the steering wheel rotation angle as variables, respectively inputting the variables into a variable transmission ratio decision algorithm for calculation, wherein the variable transmission ratio decision algorithm is used for taking the variables as the input and carrying out variable transmission ratio comprehensive control output so as to obtain different variable transmission ratios.

According to some embodiments of the present invention, the status information includes vehicle bus information, redundant communication bus information, and an inter-board communication status, and the inputting the status information to a redundancy check control algorithm for redundancy processing, to obtain redundancy control information includes:

when the signal content of the vehicle bus information and the validity of the bus state are normal, directly outputting the vehicle bus information and the vehicle state;

when one of the signal content and the bus state of the vehicle bus information is abnormal, judging whether the validity of the inter-board communication state is normal or not;

And outputting the redundant communication bus information and the vehicle state when the validity of the communication state between the boards is normal and the signal content of the redundant communication bus information and the validity of the bus state are normal.

According to some embodiments of the present invention, the inputting the status information into a redundancy check control algorithm to perform redundancy processing to obtain redundancy control information, further includes:

outputting a bus and a vehicle fault state when the validity of the inter-board communication state is normal and one of the signal content of the redundant communication bus information and the bus state is abnormal;

and outputting bus and vehicle fault states when the effectiveness of the inter-board communication states is abnormal.

A steer-by-wire control system according to a second aspect of an embodiment of the present invention includes:

the vehicle state observation module is used for acquiring the state information of the vehicle and sending the state information to the redundancy check control module;

the redundancy check control module is used for receiving the state information and inputting the state information into a redundancy check control algorithm for redundancy processing to obtain redundancy control information;

the circulation control algorithm module is used for carrying out output processing according to the redundant control information to obtain driving mode circulation check output and vehicle speed information circulation check output;

The comprehensive decision control algorithm module is used for carrying out variable transmission ratio decision calculation according to the driving mode cyclic check output and the vehicle speed information cyclic check output to obtain a decided variable transmission ratio; and performing variable transmission ratio control on the steering system by utilizing the determined variable transmission ratio.

The steer-by-wire control system provided by the embodiment of the invention has at least the following beneficial effects:

The method comprises the steps of inputting state information of a vehicle, which is acquired by a vehicle state observation module, into a redundancy check control module, and performing redundancy processing on the state information by using a redundancy check control algorithm, so that high-safety redundancy control information is provided, and safety is improved; and the redundant control information is output through a circulation control algorithm module to obtain driving mode circulation check output and vehicle speed information circulation check output, then the content after check output is subjected to variable transmission ratio decision calculation through a comprehensive decision control algorithm module, the decided variable transmission ratio is used as external output to perform variable transmission ratio control, the variable transmission ratio function of steer-by-wire is realized, and the steering-by-wire variable transmission ratio control strategy for improving the stability of the vehicle is designed, so that the problem of vehicle stability caused by variable transmission ratio output under the conditions of switching different driving modes and changing different vehicle speeds of a steering-by-wire control system is solved, the potential risk of vehicle instability is avoided, and the driving experience of a user is improved.

According to some embodiments of the invention, the status information includes a driving mode, a driving mode switching request, and a steering wheel angle, and the cyclic control algorithm module includes a driving mode cyclic control algorithm module for:

According to some embodiments of the invention, the status information includes vehicle speed and steering wheel angle, and the cycle control algorithm module includes a vehicle speed cycle control algorithm module for:

acquiring the current vehicle speed;

According to some embodiments of the invention, the vehicle speed cycle control algorithm module is further configured to:

When the vehicle speed difference between the updated vehicle speed and the vehicle speed at the last moment is in a third preset range, continuing to update the vehicle speed;

The comprehensive decision control algorithm module is also used for:

A vehicle controller according to a third aspect of embodiments of the invention includes at least one processor; and a memory storing instructions that, when executed by the at least one processor, perform the steer-by-wire ratio control method of the first aspect of the embodiments described above.

The vehicle controller according to the embodiment of the invention has at least the following beneficial effects:

the vehicle controller executes the drive-by-wire steering variable transmission ratio control method of the embodiment, can realize the variable transmission ratio function of drive-by-wire steering, solves the problem of vehicle stability caused by variable transmission ratio output under the conditions of different driving modes switching and different vehicle speeds of the drive-by-wire steering control system by designing a drive-by-wire steering variable transmission ratio control strategy for improving the vehicle stability, avoids potential vehicle instability risk and improves the driving experience of users.

A vehicle according to a fourth aspect of an embodiment of the present invention includes the steer-by-wire control system according to the second aspect of the embodiment described above, or the vehicle controller according to the third aspect of the embodiment described above.

Because the vehicle adopts all the technical schemes of the steer-by-wire control system or the vehicle controller of the above embodiments, the vehicle has at least all the beneficial effects brought by the technical schemes of the above embodiments, and the description thereof is omitted.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

FIG. 1 is a block diagram of a main controller in a steer-by-wire control system according to an embodiment of the present invention;

FIG. 2 is an overall control logic diagram of a steer-by-wire ratio control method according to an embodiment of the present invention;

FIG. 3 is a flow chart of a steer-by-wire ratio control method according to an embodiment of the present invention;

FIG. 4 is a control flow diagram of a redundancy check control algorithm in one embodiment of the present invention;

FIG. 5 is a control flow diagram of a driving pattern loop checking algorithm in an embodiment of the invention;

FIG. 6 is a control flow diagram of a vehicle speed loop verification algorithm in an embodiment of the invention;

FIG. 7 is a flow chart of variable ratio control in an embodiment of the invention;

FIG. 8 is a control logic diagram of a variable ratio decision algorithm in accordance with one embodiment of the present invention.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

In the description of the present invention, it should be understood that the azimuth or positional relationship indicated by the terms upper, lower, etc. are based on the azimuth or positional relationship shown in the drawings, and are merely for convenience of description and simplification of the description, and are not indicative or implying that the apparatus or element in question must have a specific azimuth, be constructed and operated in a specific azimuth, and thus should not be construed as limiting the present invention.

In the description of the present invention, plural means two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and the above, below, within, etc. are understood to include the present number. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, it should be noted that terms such as arrangement, installation, connection, etc. should be construed broadly, and those skilled in the art may reasonably determine the specific meaning of the foregoing terms in the present invention in combination with the specific content of the technical solution.

The following description of the embodiments of the present invention will be made with reference to the accompanying drawings, in which it is apparent that the embodiments described below are some, but not all embodiments of the invention.

According to the steer-by-wire control system provided by the embodiment of the invention, the steer-by-wire control system is suitable for a steer-by-wire vehicle, is particularly used for controlling a transmission ratio, and is described below by way of a specific example.

It will be appreciated that the steer-by-wire control system is comprised of three main components, a steering wheel assembly, a steering actuator assembly and a main controller (ECU), as well as associated auxiliary systems. The steering wheel assembly comprises a steering wheel, a steering wheel angle sensor, a torque sensor and a steering wheel aligning torque motor. The main function of the steering wheel assembly is to convert the steering intention of the driver (by measuring the steering wheel angle) into a digital signal and transmit the digital signal to the main controller; and meanwhile, the moment signal sent by the main controller is received to generate a steering wheel aligning moment so as to provide corresponding road feel information for a driver. The steering execution assembly comprises a front wheel steering angle sensor, a steering execution motor, a steering motor controller, a front wheel steering assembly and the like. The steering execution assembly is used for receiving the command of the main controller, and controlling the steering wheels to rotate through the steering motor controller so as to realize the steering intention of a driver.

The main controller analyzes and processes the collected signals, judges the motion state of the vehicle, sends instructions to the steering wheel return positive motor and the steering motor, and controls the work of the two motors so as to reduce the compensation task of a driver on the change of the steering characteristic of the vehicle along with the change of the vehicle speed and lighten the burden of the driver. Meanwhile, the controller can also recognize the operation instruction of the driver and judge whether the steering operation of the driver is reasonable in the current state. When the vehicle is in an unstable state or the driver gives out an error command, the steer-by-wire control system can shield the error steering operation of the driver, and automatically perform stability control, so that the vehicle is restored to the stable state as soon as possible.

The steering control system by wire detects steering data of a driver through a sensor, then transmits signals to an ECU on the vehicle through a data bus, and obtains feedback commands from the steering control system; the steer-by-wire control system also obtains steering commands from the steering mechanism for the driver and obtains wheel conditions from the steering system, thereby commanding movement of the entire steering system. The steering system controls the wheels to rotate to a required angle, and feeds back the rotation angle and the rotation torque of the wheels to the rest of the system, such as a steering control mechanism, so that a driver obtains road feel, and the magnitude of the road feel can be controlled by the steering control system according to different conditions, thereby having the effects of improving the safety performance of the vehicle, improving the driving characteristics and the like.

Because the mechanical connection of the intermediate shaft is canceled between the road feel simulator and the drive-by-wire steering actuator, the drive-by-wire steering system can perform variable transmission ratio control, and the variable transmission ratio control can provide different vehicle corner outputs through different inputs of a driver under different driving modes, different vehicle speeds and the like. In the related art, the problem of common pain points exists in a variable transmission ratio decision algorithm, under the condition that a driving mode is switched and the vehicle speed is obviously changed, the steering angle of execution of variable transmission ratio output at the moment has deviation, a driver can feel obvious phenomena of vehicle instability, excessive steering, insufficient steering and the like, and a new control algorithm is required to be designed to solve the problem of the pain points so as to solve the potential risk of vehicle instability and improve the driving experience of a user.

Referring to fig. 1 and fig. 2, in the embodiment of the present invention, a main controller is provided with a vehicle state observation module, a redundancy check control module, a cycle control algorithm module and a comprehensive decision control algorithm module, where the vehicle state observation module is used to obtain state information of a vehicle, the state information of the vehicle can be understood as input information of a driver and the vehicle, and mainly includes contents such as a driving mode, a vehicle speed, a steering wheel angle, a steering wheel rotation speed, vehicle bus information, redundant communication bus information, etc., and the vehicle state observation module processes the state information, such as screening, integration, etc., and inputs the processed state information to the redundancy check control module.

Referring to fig. 1 and 2, after receiving the processed state information, the redundancy check control module inputs the state information into a redundancy check control algorithm to perform redundancy processing, so as to obtain redundancy control information, and provide high-safety redundancy control information for a subsequent functional module, so as to improve safety. Specifically, the redundancy check control algorithm is used for performing redundancy check on information such as driving mode, vehicle speed, steering wheel angle, steering wheel rotating speed, vehicle bus information, redundancy communication bus information and the like.

For example, the redundant driving mode is obtained by performing redundancy processing on the driving mode, the redundant steering wheel angle is obtained by performing redundancy processing on the steering wheel angle, and then the redundant driving mode and the redundant steering wheel angle are output to the subsequent functional modules. The redundant control information may also include, by way of example only, communication redundancy, power redundancy, and the like.

Referring to fig. 1 and 2, the redundancy check control module outputs redundancy control information to the circulation control algorithm module, and performs output processing on the redundancy control information by using the circulation control algorithm module, for example, the redundancy check control algorithm performs redundancy check processing on a driving mode, a vehicle speed, a steering wheel angle and a steering wheel rotating speed to obtain a redundancy driving mode, a redundancy vehicle speed, a redundancy steering wheel angle and a redundancy steering wheel rotating speed, and the circulation control algorithm module calculates according to the redundancy driving mode, the redundancy vehicle speed, the redundancy steering wheel angle and the redundancy steering wheel rotating speed, and can output and obtain driving mode circulation check output and vehicle speed information circulation check output.

Referring to fig. 1 and 2, the circulation control algorithm module inputs the obtained driving mode circulation check output and the vehicle speed information circulation check output to the comprehensive decision control algorithm module, the driving mode circulation check output and the vehicle speed information circulation check output can be understood as contents of check output, the comprehensive decision control algorithm module receives the contents of check output to perform variable transmission ratio decision calculation, the decided variable transmission ratio can be understood as a preferred variable transmission ratio, the decided variable transmission ratio is used as a final algorithm calculation value to be output to other systems, the variable transmission ratio control is performed on the steering system, and the variable transmission ratio function of the steering by wire is realized.

According to the drive-by-wire steering control system, the drive mode and the vehicle speed can be verified through designing the drive-by-wire steering variable transmission ratio control strategy, the drive mode circulation verification output and the vehicle speed information circulation verification output are obtained, the drive-by-wire steering function is realized through the decided variable transmission ratio, the drive-by-wire steering control system has good variable transmission ratio characteristics, meanwhile, good vehicle stability is provided, the problem of vehicle stability caused by variable transmission ratio output under the condition that the drive-by-wire steering control system is switched in different drive modes and different vehicle speeds is solved, potential vehicle instability risks are avoided, and the driving experience of a user is improved.

Referring to FIG. 2, in some embodiments, the loop control algorithm module includes a driving mode loop control algorithm module for calculating an acquisition driving mode loop check output and a vehicle speed loop control algorithm module for calculating an acquisition vehicle speed information loop check output.

Specifically, the driving mode cycle control algorithm module is configured to determine a current driving mode of the vehicle according to the driving mode, the state information of the vehicle includes information such as the driving mode, a driving mode switching request, a steering wheel angle, and the like, and the current driving mode of the vehicle can be determined according to the driving mode input by the driver or the state of the vehicle; when the driving mode circulation control algorithm module receives a driving mode switching request sent by a driver, the driving mode of the vehicle is not immediately switched, and whether the current steering wheel angle is in a first preset range is judged by using a driving mode circulation check algorithm; when the steering wheel angle is within a first preset range, switching the driving mode of the vehicle is executed at the moment; when the steering wheel angle exceeds the first preset range, the current driving mode of the vehicle is maintained, that is, the switching of the driving mode is not performed.

It can be understood that the driving mode circulation control algorithm module is used for receiving different driving mode switching request inputs, and switching the driving mode only when a certain condition is met, so that the problem of vehicle stability caused in the driving mode switching process is solved, and the vehicle stability is improved. The specific implementation process comprises the following steps: the driving mode circulation control algorithm module receives the information such as steering wheel rotation angle, driving mode switching request and the like provided by the redundancy check control module, enters a driving mode circulation check algorithm when receiving the driving mode switching request command, judges whether the current steering wheel rotation angle range is in a first preset range, and aims to perform driving mode switching only in a central area range so as to ensure the consistency of variable transmission ratio output, thereby improving the stability of the vehicle.

When the steering wheel angle range is within a first preset range, switching of driving modes is executed, when the steering wheel angle range exceeds the first preset range, the condition that a driver operates at a large angle at the moment is indicated, the driving mode at the last moment is executed in the running process of the program, so that consistency of driving behaviors is ensured, driving mode circulation control is realized through the judging process, and the influence of variable transmission ratio output of different driving modes on vehicle stability is avoided. For example, the current driving mode is an energy-saving mode, when a command for switching to the movement mode is received, whether the current steering wheel angle range is within a first preset range is judged, if the steering wheel angle range is within the first preset range, switching to the movement mode is directly executed, and otherwise, switching operation is not executed.

It should be noted that when the steering wheel angle is greater than 90 ° it is understood that the driver may operate at a large steering angle, in this embodiment, the first preset range may be set to 90 ° or less, that is, when the driving mode switching request command is received and the steering wheel angle range is 90 ° or less, the switching driving mode is executed, and the first preset range is specifically selected according to the actual use requirement of the actual vehicle.

Referring to fig. 2, in some embodiments, the vehicle speed cycle control algorithm module is configured to first obtain a current vehicle speed, determine a state of the vehicle speed, where the state information of the vehicle includes information such as the vehicle speed and a steering wheel angle, and when the vehicle speed cycle control algorithm module receives a vehicle speed change request sent by a driver, the vehicle speed cycle control algorithm module does not immediately execute updating of the vehicle speed, but uses a vehicle speed cycle checking algorithm to determine whether the current steering wheel angle is within a second preset range; when the steering wheel angle is within a second preset range, updating the vehicle speed is performed at the moment; when the steering wheel angle exceeds the second preset range, the current vehicle speed is maintained, that is, the update of the vehicle speed is not performed. Wherein the driver can send different vehicle speed change requests to the vehicle by changing the pedal.

It can be understood that the vehicle speed circulation control algorithm module is used for receiving different vehicle speed inputs, and the vehicle speed change is performed under certain conditions, so that the problem of vehicle stability caused in the process of driving vehicle speed change is solved, and the vehicle stability is improved. The specific implementation process comprises the following steps: the vehicle speed circulation control algorithm module receives the information of steering wheel rotation angle, vehicle speed and the like provided by the redundancy check control module, enters a vehicle speed circulation check algorithm when receiving a vehicle speed change request, judges whether the current steering wheel rotation angle range is in a second preset range, and performs vehicle speed change only in a central area range so as to ensure the consistency of variable transmission ratio output, thereby improving the vehicle stability.

When the steering wheel angle range is within a second preset range, updating the vehicle speed; when the steering wheel angle range exceeds a second preset range, the driver is shown to change the vehicle speed under the large angle operation working condition, and the vehicle speed at the last moment is executed in the process of the program operation, so that the consistency of driving behaviors is ensured, and meanwhile, a certain stable state can be kept in the process of rapid change of the vehicle speed. For example, the preceding vehicle speed runs at a low speed, when commands of different vehicle speeds are input, it is determined whether the current steering wheel angle range is within a second preset range, if the steering wheel angle range is within the second preset range, updating the vehicle speed is directly performed, otherwise, updating operation is not performed.

It should be noted that when the steering wheel angle is greater than 90 ° it is understood that the driver may operate at a large steering angle, in which the second preset range may be set to 90 ° or less, that is, when the vehicle speed change request command is received and the steering wheel angle range is 90 ° or less, the update of the vehicle speed is performed, and the second preset range may be the same as or different from the first preset range, and the second preset range is specifically selected according to the actual use requirement of the actual vehicle.

In order to maintain a certain stable state in the rapid change process of the vehicle speed, the vehicle speed circulation control algorithm module is also used for executing the process of acquiring the updated vehicle speed and the vehicle speed at the last moment and comparing the updated vehicle speed with the vehicle speed at the last moment; when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous moment is in a third preset range, the vehicle speed change amplitude in the process of rapidly changing the vehicle speed is not excessive, and the vehicle speed updating can be continuously carried out at the moment; and when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous moment exceeds a third preset range, the vehicle speed change range in the process of rapid vehicle speed change is excessively large, and the current vehicle speed is controlled according to a vehicle speed following algorithm at the moment so as to control the vehicle speed change range and avoid the influence on the stability of the vehicle due to the excessively rapid vehicle speed change. The third preset range may be set to 10km/h, 15km/h, 18 km/h, or the like, for example, when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous time is 15km/h or less, the updating of the vehicle speed is continued.

It should be noted that, the vehicle speed following algorithm may adjust the vehicle speed according to the movement information such as the position, the speed, the acceleration, etc., for example, the speed increasing rate or the speed decreasing rate of the vehicle speed is controlled according to the acceleration and the current speed; there are also a number of factors to be considered, such as the performance of the vehicle itself, road conditions, traffic signals, external disturbances, etc. The vehicle speed circulation control is realized through the judging process, and the influence of variable transmission ratio output of different vehicle speeds on the stability of the vehicle is avoided. In some embodiments, the movement state data of the front vehicle can also be obtained in real time, and the driving strategy to be adopted by the following vehicle can be calculated according to the data, so that the following vehicle can closely follow the front vehicle and keep proper following distance, speed and the like.

Referring to fig. 8, in some embodiments, the integrated decision control algorithm module receives the driving mode cyclic check output and the vehicle speed information cyclic check output by the driving mode cyclic control algorithm module and the vehicle speed cyclic control algorithm module, performs variable transmission ratio decision algorithm control, and outputs a variable transmission ratio for steering, thereby providing a good variable transmission ratio driving experience for a user. The specific implementation process comprises the following steps: the comprehensive decision control algorithm module receives the driving mode, the vehicle speed and other information provided by the driving mode circulation control algorithm module and the vehicle speed circulation control algorithm module, and designs a variable transmission ratio decision algorithm according to different driving modes, vehicle speeds and steering wheel angles as inputs.

It can be understood that the relation between the variable transmission ratio and the driving mode, the vehicle speed and the steering wheel rotation angle is clarified through the comprehensive decision control algorithm module, so that the problem of vehicle stability caused by variable transmission ratio output under the conditions of switching of different driving modes and different vehicle speeds in the steer-by-wire can be solved, potential vehicle instability risks are avoided, and vehicle stability and user driving experience are improved.

The steer-by-wire ratio control method according to the embodiment of the present invention, which is applied to the steer-by-wire control system of the above embodiment, is described with reference to fig. 2 to 8, and with particular reference to the system schematic diagram shown in fig. 1, the steer-by-wire ratio control method will be described below by way of a particular example.

Referring to fig. 2 and 3, the steer-by-wire ratio control method provided by the embodiment of the present invention includes, but is not limited to, the following:

step S100, acquiring state information of a vehicle, and inputting the state information into a redundancy check control algorithm for redundancy processing to obtain redundancy control information;

Step S200, performing output processing according to the redundant control information to obtain driving mode cyclic check output and vehicle speed information cyclic check output;

step S300, carrying out variable transmission ratio decision calculation according to the driving mode cyclic check output and the vehicle speed information cyclic check output to obtain a decided variable transmission ratio;

and step S400, performing variable transmission ratio control on the steering system by utilizing the determined variable transmission ratio.

As can be understood from fig. 1, in step S100, the vehicle state observation module is configured to obtain state information of a vehicle, where the state information of the vehicle may be understood as input information of a driver and the vehicle, and mainly includes contents such as a driving mode, a vehicle speed, a steering wheel angle, a steering wheel rotation speed, vehicle bus information, and redundant communication bus information, and the vehicle state observation module processes the state information.

Referring to fig. 2, it can be understood that after the redundancy check control module receives the processed state information, the state information is input to a redundancy check control algorithm to perform redundancy processing, so as to obtain redundancy control information, and a steer-by-wire redundancy check strategy is adopted to provide high-safety redundancy control information for a subsequent functional module, so as to improve system safety.

Specifically, the redundancy check control algorithm is used for performing redundancy check on information such as driving mode, vehicle speed, steering wheel angle, steering wheel rotating speed, vehicle bus information, redundancy communication bus information and the like. For example, the redundant driving mode is obtained by performing redundancy processing on the driving mode, the redundant steering wheel angle is obtained by performing redundancy processing on the steering wheel angle, and then the redundant driving mode and the redundant steering wheel angle are output to the subsequent functional modules. The redundant control information may also include, by way of example only, communication redundancy, power redundancy, and the like.

In step S200, the redundancy check control module outputs the redundancy control information to the cyclic control algorithm module, and performs output processing on the redundancy control information by using the cyclic control algorithm module, for example, the redundant driving mode, the redundant vehicle speed, the redundant steering wheel angle and the redundant steering wheel rotating speed are obtained after the redundancy check processing is performed on the driving mode, the vehicle speed, the steering wheel angle and the steering wheel rotating speed by using the redundancy check control algorithm, and the cyclic control algorithm module calculates according to the redundant driving mode, the redundant vehicle speed, the redundant steering wheel angle and the redundant steering wheel rotating speed, and can output and obtain the driving mode cyclic check output and the vehicle speed information cyclic check output.

In step S300, the circulation control algorithm module inputs the obtained driving mode circulation check output and the vehicle speed information circulation check output to the comprehensive decision control algorithm module, the driving mode circulation check output and the vehicle speed information circulation check output can be understood as contents of check output, the comprehensive decision control algorithm module receives the contents of check output to perform variable transmission ratio decision calculation, a decided variable transmission ratio is obtained, and the decided variable transmission ratio can be understood as a preferable variable transmission ratio. In step S400, the decided variable transmission ratio is used as a final algorithm calculation value to be outputted to other systems, and the variable transmission ratio control is performed on the steer-by-wire system, so as to realize the variable transmission ratio function of steer-by-wire.

According to the drive-by-wire steering control system, the drive mode and the vehicle speed can be verified by designing the drive-by-wire steering variable transmission ratio control strategy, the drive mode circulation verification output and the vehicle speed information circulation verification output are output, and the drive-by-wire steering function is realized by the determined variable transmission ratio, so that the drive-by-wire steering control system has good variable transmission ratio characteristics, good vehicle stability is provided, the problem of vehicle stability caused by variable transmission ratio output under the condition that the drive-by-wire steering control system is switched in different drive modes and different vehicle speeds is changed is solved, potential vehicle instability risks are avoided, and the driving experience of a user is improved.

Referring to fig. 4, in some embodiments, the step S100 specifically includes, but is not limited to, the following:

step S110, judging the validity of signal content and the validity of bus state for the bus information of the vehicle, the redundant communication bus information and the communication state between boards;

Step S120, when the signal content of the vehicle bus information and the validity of the bus state are normal, the vehicle bus information and the vehicle state are directly output;

Step S130, judging whether the validity of the inter-board communication state is normal or not when one of the signal content of the vehicle bus information and the bus state is abnormal;

Step S140, when the validity of the communication state between boards is normal, and the signal content of the redundant communication bus information and the validity of the bus state are normal, the redundant communication bus information and the vehicle state are output;

step S150, when the validity of the communication state between boards is normal, and one of the signal content of the redundant communication bus information and the bus state is abnormal, outputting a bus and a vehicle fault state;

step S160, outputting a bus and a vehicle failure state when there is an abnormality in the validity of the inter-board communication state.

It can be understood that the state information acquired by the vehicle state observation module includes vehicle bus information, redundant communication bus information and an inter-board communication state, and the redundancy check control module inputs the state information to the redundancy check control algorithm to perform redundancy processing so as to acquire the redundancy control information.

Specifically, the redundancy check control module receives the vehicle bus information, the redundant communication bus information, the inter-board communication state and other related state and fault information provided by the vehicle state observation module, wherein the redundant communication bus is also called an auxiliary bus; the master controller judges the signal content validity and the bus state validity, and if the signal content validity and the bus state validity of the vehicle bus are normal, the master controller directly outputs the vehicle bus information and the vehicle state; if the signal content validity and the bus state validity of the vehicle bus are abnormal, continuing to judge the validity of the inter-board communication state; outputting a bus and a vehicle fault state if the validity of the inter-board communication state is abnormal; if the validity of the inter-board communication state is normal, continuing to judge the signal content validity and the bus state validity of the redundant communication bus information; if the signal content validity and the bus state validity of the redundant communication bus are normal, outputting the redundant communication bus information and the vehicle state; outputting a bus and a vehicle fault state if the signal content validity and the bus state validity of the redundant communication bus have an abnormality; and through the redundancy control algorithm, a final redundancy result is determined and a redundancy strategy is output. The steer-by-wire redundancy check strategy is adopted to provide high-safety redundancy control information for the subsequent functional modules so as to improve the system safety.

Referring to fig. 5, in some embodiments, the step S200 specifically includes, but is not limited to, the following:

step S210, determining the current driving mode of the vehicle according to the driving mode;

step S220, when a driving mode switching request is received, judging whether the current steering wheel angle is in a first preset range or not by using a driving mode cycle checking algorithm;

Step S230, when the steering wheel angle is within a first preset range, the driving mode of the vehicle is switched;

in step S240, when the steering wheel angle exceeds the first preset range, the current driving mode of the vehicle is maintained.

It may be understood that the circulation control algorithm module includes a driving mode circulation control algorithm module and a vehicle speed circulation control algorithm module, and the steps S210 to S240 are executed by the driving mode circulation control algorithm module, and the driving mode circulation check output can be calculated and obtained by the driving mode circulation control algorithm module.

Specifically, in step S210, the current driving mode of the vehicle may be determined according to the driving mode input by the driver or the state of the vehicle, which includes an energy saving mode, a normal mode, a sport mode, an off-road mode, and the like. In step S220, when the driving mode cycle control algorithm module receives the driving mode switching request sent by the driver, the driving mode switching of the vehicle is not immediately executed, but the driving mode cycle check algorithm is used to determine whether the current steering wheel angle is within the first preset range; when the steering wheel angle is within a first preset range, switching the driving mode of the vehicle is executed at the moment; when the steering wheel angle exceeds the first preset range, the current driving mode of the vehicle is maintained, that is, the switching of the driving mode is not performed.

Describing a specific example, the driving mode cycle control algorithm module receives the information such as the steering wheel angle, the driving mode switching request and the like provided by the redundancy check control module, and in step S220, when the driving mode switching request command is received, it is determined whether the current steering wheel angle range is within the first preset range by using the driving mode cycle check algorithm, and the purpose of the algorithm is to perform the driving mode switching only within the central area range, so as to ensure the consistency of the variable transmission ratio output, thereby improving the vehicle stability.

In step S230, when the steering wheel angle range is within the first preset range, a switched driving mode is performed; in step S240, when the steering wheel angle range exceeds the first preset range, it indicates that the driver is in the large angle operating condition at this time, and the driving mode at the last moment is executed during the running process of the program, so as to ensure the consistency of the driving behavior, and the driving mode circulation control is implemented through the above-mentioned judging process, so that the influence of the variable transmission ratio output of different driving modes on the stability of the vehicle is avoided. For example, the current driving mode is a normal mode, when a command for switching to the sport mode is received, whether the current steering wheel angle range is within a first preset range is judged, if the steering wheel angle range is within the first preset range, switching to the sport mode is directly executed, and otherwise, switching operation is not executed.

Referring to fig. 6, in some embodiments, the step S200 specifically includes, but is not limited to, the following:

step S250, obtaining the current vehicle speed;

Step S260, when a control command of the vehicle speed is received, judging whether the current steering wheel angle is in a second preset range by utilizing a vehicle speed circulation checking algorithm;

step S270, when the steering wheel angle is in the second preset range, the vehicle speed is updated;

in step S280, when the steering wheel angle exceeds the second preset range, the current vehicle speed is maintained.

It can be understood that the steps S250 to S280 are executed by the vehicle speed circulation control algorithm module, the current vehicle speed can be obtained by the vehicle speed circulation control algorithm module, the state of the vehicle speed is judged, the state information of the vehicle includes information such as the vehicle speed and the steering wheel angle, when the vehicle speed change request sent by the driver is received, the update of the vehicle speed is not immediately executed, and the vehicle speed circulation check algorithm is utilized to judge whether the current steering wheel angle is in the second preset range; when the steering wheel angle is within a second preset range, updating the vehicle speed is performed at the moment; when the steering wheel angle exceeds the second preset range, the current vehicle speed is maintained, that is, the update of the vehicle speed is not performed. Wherein the driver can send different vehicle speed change requests to the vehicle by changing the pedal.

Describing a specific example, the vehicle speed cycle control algorithm module receives the information such as the steering wheel angle and the vehicle speed provided by the redundancy check control module, and in step S260, when a vehicle speed change request is received, the vehicle speed cycle control algorithm is entered to determine whether the current steering wheel angle range is within a second preset range, and the purpose of the algorithm is to perform the execution of the vehicle speed change only within the central area range, so as to ensure the consistency of the variable transmission ratio output, thereby improving the vehicle stability. That is, the vehicle speed change is performed only when a certain condition is satisfied, so as to solve the problem of vehicle stability caused during the driving speed change.

In step S270, when the steering wheel angle range is within the second preset range, updating the vehicle speed is performed; in step S280, when the steering wheel angle range exceeds the second preset range, it indicates that the driver is performing a change in vehicle speed under the large angle operating condition, and the vehicle speed at the previous moment is executed during the running process of the program, so as to ensure consistency of driving behavior, and meanwhile, in order to maintain a certain stable state during the rapid change of vehicle speed. For example, the preceding vehicle speed runs at a low speed, when commands of different vehicle speeds are input, it is determined whether the current steering wheel angle range is within a second preset range, if the steering wheel angle range is within the second preset range, updating the vehicle speed is directly performed, otherwise, updating operation is not performed.

Referring to fig. 6, in some embodiments, after performing step S270, further includes:

Step S271, obtaining and comparing the updated vehicle speed and the vehicle speed at the previous moment;

Step S272, when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous moment is in a third preset range, continuing to execute the updating of the vehicle speed;

Step S273, when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous moment exceeds the third preset range, the current vehicle speed is controlled according to the vehicle speed following algorithm so as to control the variation range of the vehicle speed.

It can be understood that in step S271, the updated vehicle speed and the vehicle speed at the previous moment are obtained and compared; in step S272, when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous moment is within the third preset range, it indicates that the magnitude of the vehicle speed change during the rapid vehicle speed change is not excessive, and at this time, the update of the vehicle speed can be continuously performed; when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous moment exceeds a third preset range, the vehicle speed change range in the process of rapid vehicle speed change is excessively large, and the current vehicle speed is controlled according to a vehicle speed following algorithm at the moment so as to control the vehicle speed change range, and the problem that the stability of the vehicle is affected due to excessively rapid vehicle speed change is avoided, so that a certain stable state can be maintained in the process of rapid vehicle speed change. The third preset range may be set to 10km/h, 15km/h, 18 km/h, etc., for example, when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the previous time is less than or equal to 15km/h, the update of the vehicle speed is continuously performed, ensuring that the vehicle speed can be changed smoothly.

Referring to fig. 7, the step S300 specifically includes, but is not limited to, the following:

step S310, receiving driving mode cyclic check output and vehicle speed information cyclic check output;

Step S320, taking the driving mode, the vehicle speed and the steering wheel rotation angle as variables, respectively inputting the variables into a variable transmission ratio decision algorithm for calculation, wherein the variable transmission ratio decision algorithm is used for taking the variables as the input and performing variable transmission ratio comprehensive control output so as to obtain different variable transmission ratios.

Referring to fig. 8, it may be understood that the driving mode cycle check output includes a driving mode obtained by processing a driving mode cycle check algorithm, the vehicle speed information cycle check output includes a vehicle speed obtained by processing a vehicle speed cycle check algorithm, the integrated decision control algorithm module designs a variable transmission ratio decision algorithm according to different driving modes, vehicle speeds and steering wheel angles as inputs, and when receiving information such as the driving modes and the vehicle speeds, the variable transmission ratio decision algorithm may implement control output with the three variables as inputs, and then implement variable transmission ratio integrated control, thereby implementing different variable transmission ratios. The relation of the variable transmission ratio along with the driving mode, the vehicle speed and the steering wheel rotation angle is clarified through the comprehensive decision control algorithm module, the problem of vehicle stability caused by variable transmission ratio output under the conditions of switching of different driving modes and different vehicle speeds in the steer-by-wire mode can be solved, potential vehicle instability risks are avoided, and vehicle stability and user driving experience are improved.

In addition, an embodiment of the present invention further provides a vehicle controller, including: at least one processor; and a memory storing instructions that, when executed by the at least one processor, perform the steer-by-wire ratio control method of the above embodiment.

The processor and memory in the vehicle controller may be connected by a bus, for example. The memory, as a non-transitory computer readable storage medium, may be used to store non-transitory software programs as well as non-transitory computer executable programs. In addition, the memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk memory, flash memory device, or other non-transitory solid state storage device. In some embodiments, the memory optionally includes memory remotely located relative to the control processor, which may be connected to the controller via a network.

The non-transitory software programs and instructions required to implement the control methods of the above embodiments are stored in the memory, and when executed by the processor, the control methods of the above embodiments are performed, for example, the method steps S100 to S400 in fig. 3, the method steps S110 to S160 in fig. 4, the method steps S210 to S240 in fig. 5, the method steps S250 to S273 in fig. 6, and the like described above are performed.

The above described apparatus embodiments are merely illustrative, wherein the units illustrated as separate components may or may not be physically separate, i.e. may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

The embodiment of the invention also provides a vehicle, which comprises the steer-by-wire control system or the vehicle controller. The vehicle may be a private car such as a sedan, SUV, MPV, or a pick-up card. The vehicle may also be an operator vehicle such as a minibus, bus, minivan or large trailer, etc. The vehicle can be an oil vehicle or a new energy vehicle. When the vehicle is a new energy vehicle, the vehicle can be a hybrid vehicle or a pure electric vehicle.

The vehicle adopts the vehicle controller to execute the drive-by-wire steering transmission ratio control method, the driving mode and the vehicle speed can be checked through designing the drive-by-wire steering transmission ratio control strategy, the driving mode circulation check output and the vehicle speed information circulation check output are obtained, the drive-by-wire steering function is realized through the decided transmission ratio, the drive-by-wire steering control system has good transmission ratio changing characteristics, and meanwhile, the drive-by-wire steering control system is beneficial to providing good vehicle stability, the problem of vehicle stability caused by the transmission ratio changing output under the conditions of different driving modes and different vehicle speeds of the drive-by-wire steering control system can be solved, the potential vehicle instability risk is avoided, and the driving experience of a user is improved.

Because the vehicle adopts all the technical schemes of the vehicle controller in the above embodiments, the vehicle controller at least has all the beneficial effects brought by the technical schemes in the above embodiments, and the description thereof is omitted.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of one of ordinary skill in the art.

Claims

1. A steer-by-wire ratio-change control method, characterized by comprising:

Acquiring state information of a vehicle, inputting the state information into a redundancy check control algorithm for redundancy processing to obtain redundancy control information, wherein the state information comprises a driving mode, a driving mode switching request, a steering wheel angle, a vehicle speed and a steering wheel angle;

performing variable transmission ratio control on the linear steering system by using the determined variable transmission ratio;

the output processing is performed according to the redundant control information to obtain a driving mode cyclic check output and a vehicle speed information cyclic check output, and the method comprises the following steps:

When the driving mode switching request is received, judging whether the current steering wheel angle is in a first preset range or not by using a driving mode cycle checking algorithm; executing switching of a driving mode of the vehicle when the steering wheel angle is within the first preset range; when the steering wheel angle exceeds the first preset range, maintaining the current driving mode of the vehicle;

acquiring the current vehicle speed;

when a control command of the vehicle speed is received, judging whether the current steering wheel angle is in a second preset range or not by utilizing a vehicle speed circulation checking algorithm; when the steering wheel angle is within the second preset range, updating the vehicle speed; acquiring and comparing the updated vehicle speed and the vehicle speed at the last moment, and continuously executing updating of the vehicle speed when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the last moment is in a third preset range; and when the steering wheel angle exceeds the second preset range, maintaining the current vehicle speed.

2. The steer-by-wire ratio control method according to claim 1, characterized in that when the steering wheel angle is within the second preset range, after performing updating of the vehicle speed, further comprising:

3. The drive-by-wire steering ratio control method according to claim 1, wherein the driving pattern circulation check output includes a driving pattern obtained by processing a driving pattern circulation check algorithm, and the vehicle speed information circulation check output includes a vehicle speed obtained by processing a vehicle speed circulation check algorithm;

4. The control method for a steer-by-wire ratio according to claim 1, wherein the status information includes vehicle bus information, redundant communication bus information, and an inter-board communication status, and wherein the inputting the status information to a redundancy check control algorithm for redundancy processing, to obtain the redundant control information, includes:

5. The control method for a steer-by-wire ratio according to claim 4, wherein said inputting the state information to a redundancy check control algorithm for redundancy processing to obtain redundancy control information, further comprising:

6. A steer-by-wire control system, comprising:

The vehicle state observation module is used for acquiring state information of a vehicle and sending the state information to the redundancy check control module, wherein the state information comprises a driving mode, a driving mode switching request, a steering wheel corner, a vehicle speed and a steering wheel corner;

The comprehensive decision control algorithm module is used for carrying out variable transmission ratio decision calculation according to the driving mode cyclic check output and the vehicle speed information cyclic check output to obtain a decided variable transmission ratio; and the gear ratio is controlled by the gear ratio after decision making;

Wherein the circulation control algorithm module comprises a driving mode circulation control algorithm module and a vehicle speed circulation control algorithm module, the driving mode circulation control algorithm module is used for: determining a current driving mode of the vehicle according to the driving mode; when the driving mode switching request is received, judging whether the current steering wheel angle is in a first preset range or not by using a driving mode cycle checking algorithm; executing switching of a driving mode of the vehicle when the steering wheel angle is within the first preset range; when the steering wheel angle exceeds the first preset range, maintaining the current driving mode of the vehicle;

The vehicle speed circulation control algorithm module is used for: acquiring the current vehicle speed; when a control command of the vehicle speed is received, judging whether the current steering wheel angle is in a second preset range or not by utilizing a vehicle speed circulation checking algorithm; when the steering wheel angle is within the second preset range, updating the vehicle speed; acquiring the updated vehicle speed and the vehicle speed at the previous moment, and comparing the updated vehicle speed with the vehicle speed at the previous moment; when the vehicle speed difference between the updated vehicle speed and the vehicle speed at the last moment is in a third preset range, continuing to update the vehicle speed; and when the steering wheel angle exceeds the second preset range, maintaining the current vehicle speed.

7. The steer-by-wire control system of claim 6, wherein the vehicle speed cycle control algorithm module is further configured to:

8. The steer-by-wire control system according to claim 6, wherein the driving pattern cyclic check output includes a driving pattern processed by a driving pattern cyclic check algorithm, and the vehicle speed information cyclic check output includes a vehicle speed processed by a vehicle speed cyclic check algorithm;

The comprehensive decision control algorithm module is also used for:

9. A vehicle controller, characterized by comprising:

At least one processor;

And a memory storing instructions that, when executed by the at least one processor, perform the steer-by-wire ratio control method of any one of claims 1 to 5.

10. A vehicle comprising the steer-by-wire control system according to any one of claims 6 to 8 or the vehicle controller according to claim 9.