Wire-controlled steering feel feedback method, wire-controlled steering system, vehicle and electronic equipment

Abstract

The present invention proposes a steer-by-wire feel feedback method, a steer-by-wire system, a vehicle and an electronic device, and belongs to the field of vehicle braking technology. The method includes: obtaining the current speed of the vehicle in which the steer-by-wire system is located; obtaining the current steering wheel limit position according to the vehicle speed, the current variable transmission ratio ratio of the steer-by-wire system and the maximum rack position of the lower steering; obtaining the terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel; and feeding back the terminal protection torque to the feel motor to instruct the feel motor to rotate according to the terminal protection torque. In this way, in the process of obtaining the current steering wheel limit position, the influence of the real-time vehicle speed, the variable transmission ratio ratio and the maximum rack position of the lower steering are taken into account, so that the real-time steering wheel limit position that changes with the vehicle speed is more accurate, and then the feel feedback is performed in the form of a slow decrease in the steering wheel limit position, which greatly optimizes the feel feedback effect.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle braking, and in particular to a steering-by-wire feel feedback method, a steering-by-wire system, a vehicle and an electronic device. Background Art

[0002] Steer-by-wire technology is an advanced automotive steering system that eliminates the mechanical connection between the upper steering system (including the steering wheel) and the lower steering system (including the steering wheel). The driver's operating actions are converted into electrical signals through sensors, which are analyzed and processed and then directly transmitted to the actuator through wires.

[0003] The upper steering feel motor is a device used in the wire control steering system to simulate the driver's feel feedback in the traditional steering system. During the steering process, the motor simulates the steering resistance through electrical signals, provides the driver with road feedback, prompts the driver's current steering wheel angle limit, and protects the terminal mechanical structure, thereby improving the driving experience. However, the feedback accuracy of the feel motor in the related technology is poor, which seriously affects driving safety and driving experience. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a steer-by-wire feel feedback method, a steer-by-wire system, a vehicle and an electronic device, which improve the feedback accuracy of the feel motor and greatly optimize the feel feedback effect.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present invention provides a method for feedback of a steer-by-wire feel, which is applied to a master controller of a steer-by-wire system, wherein the steer-by-wire system further comprises a tactile motor in communication with the master controller, and the method comprises:

[0007] Obtaining a current speed of the vehicle in which the steer-by-wire system is located;

[0008] Obtaining a current steering wheel limit position according to the vehicle speed, a current variable transmission ratio of the steer-by-wire system, and a maximum rack position of the lower steering;

[0009] Obtaining a terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel;

[0010] The terminal protection torque is fed back to the hand-feel motor to instruct the hand-feel motor to rotate according to the terminal protection torque.

[0011] Optionally, the step of obtaining the current steering wheel limit position according to the vehicle speed, the current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering comprises:

[0012] Obtaining a current unrestricted limit position of the steering wheel according to a current variable transmission ratio of the steer-by-wire system and a maximum rack position of the lower steering;

[0013] The current steering wheel limit position is obtained according to the unrestricted limit position and the angle limit of the vehicle speed.

[0014] Optionally, the step of obtaining the current steering wheel limit position according to the unrestricted limit position and the angle limit of the vehicle speed comprises:

[0015] Based on the vehicle speed and a preset angle change curve, obtaining the angle change rate corresponding to the vehicle speed; wherein the angle change curve is obtained by fitting according to calibration data;

[0016] The current steering wheel limit position is obtained according to the angle change rate and the unrestricted limit position.

[0017] Optionally, the step of obtaining the current steering wheel limit position according to the angle change rate and the unrestricted limit position comprises:

[0018] Obtaining an angle change value according to the angle change rate and the control cycle duration;

[0019] The angle change value and the unrestricted limit position are summed to obtain the current steering wheel limit position.

[0020] Optionally, the step of obtaining the terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel includes:

[0021] Obtaining the current end position distance of the steering wheel according to the steering wheel limit position and the current angle of the steering wheel;

[0022] Based on the terminal position distance, a terminal protection torque is obtained.

[0023] Optionally, the step of obtaining the terminal protection torque based on the terminal position distance includes:

[0024] Querying the reference torque and damping coefficient corresponding to the end position distance from the preset torque table and damping table respectively;

[0025] Obtaining a damping torque according to the damping coefficient and the current rotation speed of the steering wheel;

[0026] According to the reference torque and the damping torque, a terminal protection torque is obtained.

[0027] Optionally, the step of obtaining the current unrestricted limit position of the steering wheel according to the current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering comprises:

[0028] The current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering are multiplied to obtain the current unrestricted limit position of the steering wheel.

[0029] In a second aspect, the present invention provides a steer-by-wire feel feedback device, which is applied to a master controller of a steer-by-wire system, wherein the steer-by-wire system further comprises a feel motor communicatively connected to the master controller, and the steer-by-wire feel feedback device comprises a torque calculation module and a feel feedback module;

[0030] The torque calculation module is used to obtain the current speed of the vehicle in which the wire steering system is located; obtain the current steering wheel limit position according to the vehicle speed, the current variable transmission ratio of the wire steering system and the maximum rack position of the lower steering; obtain the terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel;

[0031] The hand feeling feedback module is used to feed back the terminal protection torque to the hand feeling motor to instruct the hand feeling motor to rotate according to the terminal protection torque.

[0032] In a third aspect, the present invention provides a wire-controlled steering system, comprising a master controller and a tactile motor communicatively connected to the master controller, wherein the tactile motor is arranged on a steering wheel, and the master controller is used to implement the wire-controlled steering tactile feedback method as described in the first aspect.

[0033] In a fourth aspect, the present invention provides an electronic device, comprising a processor and a memory, wherein the memory stores a computer program executable by the processor, and the processor can execute the computer program to implement the wire-controlled steering feel feedback method as described in the first aspect.

[0034] In a fifth aspect, the present invention provides a vehicle, comprising the steer-by-wire system as described in the third aspect, or the electronic device as described in the fourth aspect.

[0035] The embodiment of the present invention provides a steer-by-wire feel feedback method, steer-by-wire system, vehicle and electronic equipment, the method comprising: obtaining the current speed of the vehicle in which the steer-by-wire system is located; obtaining the current steering wheel limit position according to the vehicle speed, the current variable transmission ratio ratio of the steer-by-wire system and the maximum rack position of the lower steering; obtaining the terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel; and feeding back the terminal protection torque to the feel motor to instruct the feel motor to rotate according to the terminal protection torque. In this way, in the process of obtaining the current steering wheel limit position, the influence of the real-time vehicle speed, the variable transmission ratio ratio and the maximum rack position of the lower steering are taken into account, so that the real-time steering wheel limit position that changes with the vehicle speed is more accurate, and then the feel feedback is performed in the form of a slow drop in the steering wheel limit position, which greatly optimizes the feel feedback effect.

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 A schematic diagram of the system architecture of a steer-by-wire system provided in an embodiment of the present invention is shown.

[0039] Figure 2 A schematic diagram of a module architecture of an electronic device provided by an embodiment of the present invention is shown.

[0040] Figure 3 A schematic flow chart of a method for providing steer-by-wire feel feedback according to an embodiment of the present invention is shown.

[0041] Figure 4 Shows Figure 3 Schematic diagram of the process flow of some sub-steps of step 13.

[0042] Figure 5 Shows Figure 4 A flowchart of some sub-steps of step 133 in FIG.

[0043] Figure 6 Shows Figure 3 Schematic diagram of the process of some sub-steps of step 15.

[0044] Figure 7 Shows Figure 6A flowchart of some sub-steps of step 153.

[0045] Figure 8 A schematic diagram of the module architecture of a steer-by-wire feel feedback device provided in an embodiment of the present invention is shown.

[0046] Explanation of the reference numerals: 10 - wire-controlled steering system; 110 - main controller; 120 - speed sensor; 130 - hand-feel motor; 140 - steering wheel; 150 - steering wheel angle sensor; 160 - front wheel angle sensor; 170 - steering execution motor; 180 - steering motor controller; 190 - front wheel steering assembly; 20 - electronic device; 210 - memory; 220 - processor; 230 - communication module; 30 - wire-controlled steering feel feedback device; 310 - torque calculation module; 320 - hand-feel feedback module. DETAILED DESCRIPTION

[0047] The transmission ratio change characteristics of the wire-controlled steering system are closely related to the vehicle speed and steering wheel angle. Different vehicle speeds and steering wheel angles correspond to different steering wheel extreme positions (i.e., steering wheel extreme angles). When the driver switches the variable transmission ratio mode of the wire-controlled steering system in a multi-mode driving mode, for example, when there are extreme angles such as 180° and 270° for the maximum steering wheel angle, the maximum extreme angle of the steering wheel changes with the switching of the variable transmission ratio mode. At different extreme end positions, the hand-feel motor is required to provide end force feedback to remind the driver that the steering has reached the extreme position. However, the relevant technology does not consider all the influencing factors of the full end extreme position, resulting in poor feedback accuracy of the hand-feel motor, which seriously affects driving safety and driving experience.

[0048] In response to the above problems, the present invention provides a concept of wire-controlled steering feel feedback, which takes into account the influence of vehicle speed changes, variable transmission ratio and maximum rack position of lower steering on the steering wheel limit position, greatly improves the feedback accuracy of the feel motor, and enhances driving safety and driving experience.

[0049] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0051] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0052] The wire control steering feel method provided by the embodiment of the present invention can be applied to Figure 1 In the illustrated steer-by-wire system 10, the steer-by-wire system 10 includes a master controller 110, a speed sensor 120, a hand-feel motor 130, a steering wheel 140, a steering wheel angle sensor 150, a front wheel angle sensor 160, a steering actuator motor 170, a steering motor controller 180, and a front wheel steering assembly 190. The master controller 110 is respectively connected to the hand-feel motor 130, the speed sensor 120, the steering wheel angle sensor 150, the front wheel angle sensor 160, and the steering motor controller 180 in a wired manner.

[0053] The steering wheel 140, the angle sensor, the torque sensor and the hand-feel motor 130 constitute an upper steering subsystem, and the front wheel angle sensor 160, the steering actuator motor 170, the steering motor controller 180 and the front wheel steering assembly 190 constitute a lower steering subsystem. The output shaft of the hand-feel motor 130 is connected to the steering wheel 140 through a transmission assembly, and the speed sensor 120 is arranged at any position of the vehicle where the wire control steering system 10 is located.

[0054] The speed sensor 120 is used to measure the vehicle speed in real time and transmit the speed to the main controller 110 .

[0055] The steering wheel angle sensor 150 is used to measure the current angle of the steering wheel 140 in real time.

[0056] The front wheel steering angle sensor 160 is used to collect the steering angle signal of the front wheel in real time and transmit it to the main controller 110 so as to understand the current steering state of the wheel.

[0057] The steering motor controller 180 is responsible for controlling the operation of the front wheel steering motor.

[0058] The front wheel steering motor is used to drive the front wheel steering assembly 190 to perform steering action according to the instruction of the steering motor controller 180 to realize the driver's steering intention. The front wheel steering assembly 190 includes a steering knuckle, a steering tie rod, etc., which convert the driving torque of the front wheel steering motor into the actual steering action of the wheel.

[0059] The overall controller 110 is used to implement steering control and the wire control online hand feel feedback method provided in the embodiment of the present invention.

[0060] The hand-feel motor 130 is used to generate a terminal protection torque according to the instruction of the main controller 110 to provide the driver with corresponding road feeling information, simulating the road surface feedback in the traditional wire-controlled steering system 10.

[0061] The master controller 110 may be a programmable logic controller, a field programmable gate array or any other programmable control device.

[0062] Please refer to Figure 2 , is a schematic diagram of a module architecture of an electronic device 20, the electronic device 20 may be Figure 1 The main controller 110 in the wire control steering system 10 is shown. The electronic device 20 includes a memory 210, a processor 220 and a communication module 230. The memory 210, the processor 220 and the communication module 230 are electrically connected to each other directly or indirectly to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines.

[0063] The memory 210 is used to store programs or data and can be, but not limited to, a random access memory, a read-only memory, a programmable read-only memory, an erasable read-only memory, an electrically erasable read-only memory, and the like.

[0064] The processor 220 is used to read / write data or programs stored in the memory 210 and execute corresponding functions. For example, Figure 1 In the illustrated steer-by-wire system 10 , the processor 220 of the master controller 110 reads the computer program stored in the memory 210 to implement the steer-by-wire feel feedback method provided in the embodiment of the present invention.

[0065] The communication module 230 is used to establish a communication connection between the electronic device 20 and other devices, and to send and receive data. For example, Figure 1 In the illustrated steer-by-wire system 10 , the master controller 110 is communicatively connected to the hand-feel motor 130 , the speed sensor 120 , etc. via the communication module 230 .

[0066] It should be understood that Figure 2The structure shown is only a schematic diagram of the structure of the electronic device 20. The electronic lock Hebei may also include Figure 2 More or fewer components as shown, or with Figure 2 Different configurations are shown. Figure 2 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0067] In order to improve the poor feedback accuracy of the hand-feel motor 130 in the wire-controlled steering system 10, and avoid the problem that the feedback of the hand-feel motor 130 is poor due to the change of vehicle speed, that is, the terminal protection torque suddenly changes, and then leads to self-steering and steering violation behavior, which affects driving safety and driving experience, the embodiment of the present invention provides a weight-controlled wire-controlled steering feel feedback method, referring to Figure 3 , including steps 11 to 17. So that: Figure 1 In the steer-by-wire system 10 shown in FIG. Figure 2 In the structure shown, when the processor 220 executes the computer program stored in the memory 210, steps 11 to 17 are implemented to more accurately perform the hand feel feedback of the steer-by-wire system 10.

[0068] Step 11, obtaining the current speed of the vehicle in which the steer-by-wire system is located.

[0069] Step 13, obtaining the current steering wheel limit position according to the vehicle speed, the current variable transmission ratio of the wire control steering system and the maximum rack position of the lower steering.

[0070] Step 15, obtaining the terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel.

[0071] Step 17, feeding back the terminal protection torque to the hand-feel motor to instruct the hand-feel motor to rotate according to the terminal protection torque.

[0072] Among them, the maximum rack position of the lower steering (also known as the maximum rack position of the lower steering) refers to the maximum displacement that the front wheel rack can achieve on the rack rod. The variable transmission ratio (also known as the variable transmission ratio) refers to the steering transmission ratio that can be dynamically adjusted according to the vehicle speed, steering requirements and driving conditions. It is a dynamically adjusted steering transmission ratio that changes according to changes in vehicle speed and driving conditions. The steering wheel limit position can be understood as the maximum angle that the front wheel can turn after a steering control is executed to apply steering force to the front wheel, under the influence of the feedback force of the front wheel in contact with the road, steering resistance and return torque, etc., that is, the maximum steering angle.

[0073] For example, in combination Figure 1In the steer-by-wire system 10 shown, after the vehicle is started and the steer-by-wire system 10 enters the working state, the speed sensor 120 obtains the current speed of the vehicle in real time and transmits the speed to the master controller 110. The master controller 110 obtains the current steering wheel limit position in real time according to the current vehicle speed, the variable transmission ratio and the maximum rack position of the lower steering. Furthermore, according to the steering wheel limit position and the current angle of the steering wheel 140, the terminal protection torque is obtained and the terminal protection torque is fed back to the hand feel motor 130. The hand feel motor 130 outputs the terminal protection torque so that the steering wheel 140 simulates the road surface feedback in the traditional steer-by-wire system 10 so that the driver can feel the steering resistance, that is, the road feel.

[0074] The variable transmission ratio mode changes with the angle and vehicle speed. For example, when driving in a fixed circle at a low speed, the variable transmission ratio changes due to the decrease in vehicle speed, which in turn causes the steering wheel limit position (i.e., the upper steering virtual end position) to change. Therefore, if all influencing factors are not considered, the vehicle speed changes too quickly, which will cause the steering wheel limit position to change, resulting in a sudden change in the steering wheel 140 feel torque, which will cause the driver to have a certain pulling feeling, seriously affecting the driving feel experience. At the same time, due to the failure to obtain accurate feel feedback in time, it is very easy to over-control and cause the vehicle to self-steer, turn against demand, and other behaviors, thereby reducing driving safety.

[0075] Therefore, in the above steps 11 to 17, various factors affecting the steering wheel limit position are taken into consideration, namely, the real-time vehicle speed, the transmission ratio, and the maximum rack position of the lower steering wheel, so that the real-time steering wheel limit position that changes with the vehicle speed is more accurate, avoiding the sudden change of the terminal protection torque due to the influence of the vehicle speed, and realizing the hand feeling feedback in the form of slow drop of the steering wheel limit position, which greatly optimizes the hand feeling feedback effect. At the same time, it can avoid the self-steering and steering against demand caused by the sudden change of the terminal protection torque, greatly improving driving safety.

[0076] Among them, the method of obtaining the current steering wheel limit position in step 13 can be flexibly selected. For example, it can be calculated using a pre-trained model, or it can be obtained after processing according to preset rules. The implementation method is not limited.

[0077] In order to obtain a more accurate current steering wheel limit position, in step 13, the idea of ​​obtaining the unrestricted limit position based on the variable transmission ratio and the lower steering maximum rack position is introduced, and then the steering wheel limit position is obtained in combination with the angle limit of the vehicle speed. Figure 4 The process of obtaining the current steering wheel limit position in step 13 includes steps 131 to 133.

[0078] Step 131, obtaining the current unrestricted limit position of the steering wheel according to the current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering.

[0079] Step 133, obtaining the current steering wheel limit position according to the unrestricted limit position and the angle limit of the vehicle speed.

[0080] The pre-configured driving mode table may be queried to use the variable transmission ratio corresponding to the current driving mode of the vehicle as the current variable transmission ratio. The variable transmission ratio may also be calculated using a variable transmission ratio formula based on the current vehicle speed. For example, the variable transmission ratio formula may be: ,in, and Characterizes the proportionality coefficient, Indicates vehicle speed. Characterizes the vehicle wheelbase, Characterizes the vehicle wheelbase, Characterizes the lateral steady-state acceleration coefficient, Characterizes the self-aligning torque coefficient, Characterizes the lateral acceleration of the vehicle. The above two methods are only examples, and their implementation methods are not limited.

[0081] Similarly, the pre-configured driving mode table may be queried, and the maximum rack position of the lower steering corresponding to the current driving mode of the vehicle may be used as the current maximum rack position of the lower steering. Alternatively, the current maximum rack position of the lower steering may be calculated using a formula, for example, the calculation formula may be: ,in, Indicates the maximum rack position of the current down-steering, Characterizes the total length of the front wheel rack (i.e. steering wheel rack), Characterizes the number of teeth on the front wheel rack, The above method is only an example, and its implementation method is not limited.

[0082] In step 131, after obtaining the current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering, the two are multiplied to obtain the current unrestricted limit position of the steering wheel.

[0083] In addition, the above-mentioned calculation method of the unrestricted limit position is only an example. When the setting of the variable transmission ratio is different, the current unrestricted limit position of the steering wheel can also be obtained by dividing the two.

[0084] After obtaining the current unrestricted limit position of the steering wheel, in step 133, the vehicle speed can be input into the pre-trained angle limit model, and the angle limit model can be used to output the angle limit corresponding to the vehicle speed, and the angle limit is added to the unrestricted limit position to obtain the current steering wheel limit position. Alternatively, the angle limit value corresponding to the current vehicle speed can be queried from a pre-configured angle limit table, and then added to the unrestricted limit position to obtain the current steering wheel limit position. The above two methods are only examples, and their implementation methods are not limited.

[0085] In order to make the acquired steering wheel limit position closer to the actual steering angle of the front wheels after the influence of the variable transmission ratio, the lower steering maximum rack position and the vehicle speed, the idea of ​​calculating the current steering wheel limit position based on the angle change rate corresponding to the vehicle speed and the unlimited limit position is introduced in step 133. Figure 5 The implementation process of step 133 includes steps 1331 to 1333.

[0086] Step 1331, based on the vehicle speed and a preset angle change curve, obtain the angle change rate corresponding to the vehicle speed. The angle change curve is obtained by fitting based on calibration data.

[0087] Step 1333, obtaining the current steering wheel limit position according to the angle change rate and the unrestricted limit position.

[0088] The rate of change of the angle corresponding to the vehicle speed is the rate of change of the steering wheel limit position caused by the vehicle speed. In the steer-by-wire system, the steering wheel limit position actually simulates the road feedback after executing a front wheel steering control (i.e., the feedback force of the tire contacting the road surface, as well as steering resistance and return torque, etc.). Therefore, the rate of change of the angle corresponding to the vehicle speed can also be understood as the limit value of the angle change of the steering wheel caused by the vehicle speed at that speed (i.e., the feedback force of the front wheel contacting the road surface, steering resistance and return torque, etc.).

[0089] For each vehicle or each steer-by-wire system, a calibration experiment can be conducted on the effect of vehicle speed on the steering wheel angle (or steering wheel extreme position) to obtain multiple calibration data (each calibration data includes vehicle speed and the angle change value caused by vehicle speed). The calibration data is then curve-fitted to obtain an angle change curve that characterizes the relationship between vehicle speed and angle change, and the angle change curve is deployed in the master controller of the steer-by-wire system. Thus, by querying the angle change curve based on the current vehicle speed, the current angle change rate can be obtained.

[0090] After obtaining the angle change rate corresponding to the vehicle speed, in step 1333, according to the angle change rate and the control cycle duration, the angle change value, i.e., the angle change value caused by the vehicle speed, can be obtained by multiplying the angle change rate and the control cycle duration. Then, the angle change value and the unrestricted limit position are summed to obtain the current steering wheel limit position.

[0091] In the above manner, in the process of calculating the steering wheel limit position, not only the unrestricted limit position of the variable transmission ratio and the maximum rack position of the lower steering are considered, but also the angle change value that changes with the vehicle speed is considered, thereby reducing the error, thereby making the steering wheel limit position closer to the actual road feedback, and greatly improving the accuracy of the steering wheel limit position.

[0092] After the precise steering wheel limit position is obtained in the above manner, the method of obtaining the terminal protection torque in step 15 can be flexibly selected. For example, a preset calculation rule can be used for calculation, or a pre-trained torque fitting model can be used for acquisition, and the implementation method is not limited.

[0093] For example, refer to Figure 6 The process of obtaining the terminal protection torque in step 15 includes steps 151 to 153.

[0094] Step 151, obtaining the end position distance of the current steering wheel according to the steering wheel limit position and the current angle of the steering wheel.

[0095] Step 153, based on the terminal position distance, obtain the terminal protection torque.

[0096] Among them, based on the terminal position distance, the method of obtaining the terminal protection torque can be flexibly selected. For example, the terminal position distance can be multiplied by a preset damping coefficient to obtain the terminal protection torque. It is also possible to take a picture of the road environment on which the vehicle is traveling to obtain an environmental picture, and obtain the vehicle's state value (such as variable transmission mode, vehicle speed, etc.), input the environmental picture, state value and terminal position distance into the pre-trained torque fitting model, and obtain the terminal protection torque output by the torque fitting model. The above methods are only examples, and their implementation methods are not limited.

[0097] In order to make the terminal protection torque closer to the actual road feel, the reference torque and damping torque corresponding to the terminal position distance are introduced in step 153 to comprehensively obtain the concept of the terminal protection torque. Figure 7 , step 153 includes the following steps 1531 to 1535.

[0098] Step 1531, respectively query the reference torque and damping coefficient corresponding to the end position distance from the preset torque table and damping table.

[0099] Step 1533, obtaining the damping torque according to the damping coefficient and the current rotation speed of the steering wheel.

[0100] Step 1535, obtaining the terminal protection torque according to the reference torque and the damping torque.

[0101] Among them, the torque table and the damping table can be tables obtained after processing the calibration data. The torque table records the reference torque corresponding to various terminal position distances, and the reference torque refers to the reference protection torque corresponding to the terminal position distance. The damping table records the damping coefficient corresponding to various terminal position distances. Therefore, by querying the torque table and the damping table, the reference torque and the damping coefficient can be obtained.

[0102] The damping torque can be obtained by multiplying the damping coefficient by the current speed of the steering wheel. The terminal protection torque can be obtained by summing the damping torque and the reference torque.

[0103] Through the above method, when calculating the terminal protection torque, both the damping coefficient of the steering wheel at different speeds and the reference torque are taken into account, so that the terminal protection torque is more accurate, thereby making the final feel feedback closer to the actual road feel feedback.

[0104] In order to further optimize the hand-feel feedback and reduce the error, the influence of the road condition can also be considered in the process of calculating the terminal protection torque. For example, a road surface image of the road where the vehicle is located can be obtained, and the road surface image can be identified using a recognition model to obtain the road condition type (for example, snow, muddy, dry asphalt, etc.). Then, the conversion ratio corresponding to the road condition type is queried from the preset conversion coefficient table, and then the reference torque and the damping torque are summed to obtain the original torque, and then the conversion ratio is multiplied by the original torque to obtain the final terminal protection torque.

[0105] In this way, the impact of road conditions on steering is taken into account in the road feel feedback, making the feedback of the hand feel motor closer to the real road feel, further optimizing the road feel feedback effect and improving driving experience and driving safety.

[0106] Based on the same concept as the above-mentioned wire control steering feel feedback method, refer to Figure 8 The embodiment of the present invention further provides a wire-controlled steering feel feedback device 30, which can be applied to Figure 1 The overall controller 110 of the steer-by-wire system 10 shown includes a torque calculation module 310 and a hand-feel feedback module 320 .

[0107] The torque calculation module 310 is used to: obtain the current speed of the vehicle in which the wire-controlled steering system is located; obtain the current steering wheel limit position based on the vehicle speed, the current variable transmission ratio of the wire-controlled steering system and the maximum rack position of the lower steering; obtain the terminal protection torque based on the steering wheel limit position and the current angle of the steering wheel.

[0108] The hand feeling feedback module 320 is used to feed back the terminal protection torque to the hand feeling motor to instruct the hand feeling motor to rotate according to the terminal protection torque.

[0109] The above-mentioned wire control steering feel feedback device 30, under the coordinated action of the torque calculation module 310 and the feel feedback module 320, takes into account various changing factors of the steering wheel limit position - real-time vehicle speed, variable transmission ratio and maximum rack position of the lower steering, so as to make the real-time steering wheel limit position that changes with the vehicle speed more accurate, avoid the instantaneous sudden change of the terminal protection torque due to the influence of the vehicle speed, and realize the feel feedback in the form of slow drop of the steering wheel limit position, which greatly optimizes the feel feedback effect. At the same time, it can avoid the self-steering, steering against demand and other behaviors caused by the sudden change of the terminal protection torque, greatly improving driving safety.

[0110] For the specific implementation and effect of the wire-controlled steering feel feedback device 30, please refer to the description of the implementation of the wire-controlled steering feel feedback method above. For example, for the specific implementation and effect of the torque calculation module 310, please refer to the description of the relevant contents of steps 11 to 15 above. For the specific implementation and effect of the feel feedback module 320, please refer to the description of the relevant contents of step 17 above, which will not be repeated here.

[0111] In addition, each module of the above-mentioned wire control steering feel feedback device 30 can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor 220 in the electronic device 20 in the form of hardware, or can be stored in the memory 210 of the electronic device 20 in the form of software, so that the processor 220 can call and execute the operations corresponding to the above-mentioned modules to implement the wire control steering feel feedback method provided above.

[0112] The embodiment of the present invention further provides a wire-controlled steering system 10, such as Figure 1 The steer-by-wire system 10 shown includes a master controller 110 and a tactile motor 130 communicatively connected to the master controller 110 . The tactile motor 130 is disposed on a steering wheel 140 . The master controller 110 is used to implement the tactile feedback method for steer-by-wire provided above.

[0113] An embodiment of the present invention also provides an electronic device 20, including a processor 220 and a memory 210, wherein the memory 210 stores a computer program that can be executed by the processor 220, and the processor 220 can execute the computer program to implement the wire-controlled steering feel feedback method as provided above.

[0114] An embodiment of the present invention further provides a vehicle, comprising the steer-by-wire system 10 as provided above, or the electronic device 20 as provided above.

[0115] The embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by the processor 220, the method for steer-by-wire feel feedback as proposed in the embodiment of the present invention is implemented.

[0116] In summary, the steer-by-wire feel feedback method, steer-by-wire system, vehicle and electronic equipment provided by the embodiments of the present invention have at least the following beneficial effects:

[0117] (I) Taking into account the change of the steering wheel limit position with vehicle speed, the steering wheel limit position is obtained by combining the angle change rate corresponding to the vehicle speed, so that the steering wheel limit position drops slowly, which is closer to the actual road feel and greatly optimizes the hand feel feedback effect;

[0118] (ii) It avoids self-steering, steering against demand and other behaviors caused by sudden changes in the terminal protection torque, making the terminal protection torque closer to the actual road feel, greatly improving driving safety.

[0119] In several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0120] In addition, the functional modules in the various embodiments of the present invention may be integrated together to form an independent part, or each module may exist independently, or two or more modules may be integrated to form an independent part.

[0121] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory, a random access memory, a magnetic disk or an optical disk.

[0122] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for feedback of steering feel by wire, characterized in that: A master controller applied to a wire-controlled steering system, wherein the wire-controlled steering system further comprises a hand-feel motor in communication with the master controller, and the method comprises: Obtaining a current speed of the vehicle in which the steer-by-wire system is located; Obtaining a current steering wheel limit position according to the vehicle speed, a current variable transmission ratio of the steer-by-wire system, and a maximum rack position of the lower steering; Obtaining a terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel; Feeding back the terminal protection torque to the hand-feel motor to instruct the hand-feel motor to rotate according to the terminal protection torque; The step of obtaining the current steering wheel limit position according to the vehicle speed, the current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering comprises: Obtaining a current unrestricted limit position of the steering wheel according to a current variable transmission ratio of the steer-by-wire system and a maximum rack position of the lower steering; Based on the vehicle speed and a preset angle change curve, the angle change rate corresponding to the vehicle speed is obtained; wherein the angle change curve is obtained by fitting according to calibration data, the calibration data includes the vehicle speed and the angle change value caused by the vehicle speed, and the angle change curve represents the relationship between the vehicle speed and the angle change; the angle change rate corresponding to the vehicle speed is the change rate of the steering wheel limit position caused by the vehicle speed; The current steering wheel limit position is obtained according to the angle change rate and the unrestricted limit position.

2. The method for steer-by-wire feel feedback according to claim 1, characterized in that: The step of obtaining the current steering wheel limit position according to the angle change rate and the unrestricted limit position comprises: Obtaining an angle change value according to the angle change rate and the control cycle duration; The angle change value and the unrestricted limit position are summed to obtain the current steering wheel limit position.

3. The method for steer-by-wire feel feedback according to claim 1 or 2, characterized in that: The step of obtaining the terminal protection torque according to the steering wheel limit position and the current angle of the steering wheel comprises: Obtaining the current end position distance of the steering wheel according to the steering wheel limit position and the current angle of the steering wheel; Based on the terminal position distance, a terminal protection torque is obtained.

4. The method for steer-by-wire feel feedback according to claim 3, characterized in that: The step of obtaining the terminal protection torque based on the terminal position distance comprises: Querying the reference torque and damping coefficient corresponding to the end position distance from the preset torque table and damping table respectively; Obtaining a damping torque according to the damping coefficient and the current rotation speed of the steering wheel; The terminal protection torque is obtained according to the reference torque and the damping torque.

5. The method for steer-by-wire feel feedback according to claim 1, characterized in that: The step of obtaining the current unrestricted limit position of the steering wheel according to the current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering comprises: The current variable transmission ratio of the steer-by-wire system and the maximum rack position of the lower steering are multiplied to obtain the current unrestricted limit position of the steering wheel.

6. A wire-controlled steering system, comprising a master controller and a hand-feel motor in communication with the master controller, wherein the hand-feel motor is arranged on a steering wheel, characterized in that: The master controller is used to implement the steering-by-wire feel feedback method according to any one of claims 1 to 5.

7. An electronic device, characterized in that: The invention comprises a processor and a memory, wherein the memory stores a computer program executable by the processor, and the processor can execute the computer program to implement the wire control steering feel feedback method according to any one of claims 1 to 5.

8. A vehicle, characterized in that: It includes the steer-by-wire system as claimed in claim 6, or the electronic device as claimed in claim 7.

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