Electric control steer-by-wire device and control method thereof

Abstract

The invention discloses an electric adjusting steer-by-wire device and a control method thereof. The electric adjusting steer-by-wire device comprises a steering wheel and a steering column, the first end of the steering column is connected with the steering wheel, and the second end of the steering column is connected with a road feeling simulation motor; the steering column comprises a sliding mechanism, a first axis in the axial direction of the sliding stroke is limited through the sliding mechanism, a second axis is limited through a rotating mechanism, and the second axis and the first axis are arranged in different planes. The steering wheel slides along a first axis to limit a first activity space and rotates around a second axis to limit a second activity space; the first motor is connected to the steering column and provides a second motor for driving the steering wheel in the first moving space through the sliding mechanism, and is connected to the steering column and provides a second motor for driving the steering wheel in the second moving space through the rotating mechanism. According to the invention, a wider steering wheel adjusting range is provided, and more accurate road feeling simulation is realized while steer-by-wire is realized.

Description

Technical Field

[0001] This invention relates to the field of automotive steering control technology, specifically to an electrically adjustable steer-by-wire device and its control method. Background Technology

[0002] Most existing car steering systems do not use steer-by-wire; instead, they utilize a traditional steering column, which is physically connected to the steering wheel via an intermediate shaft. The steering wheel provides force feedback to the steering column, which is then amplified proportionally by a power steering motor and output to the wheels to achieve the steering function.

[0003] The steer-by-wire system eliminates the intermediate shaft and uses a road feel simulation motor at the end of the steering column to ensure that the driver's steering feel is consistent with that of a traditional steering system. When the steering wheel is turned, the motor collects signals and controls the steering gear to adjust the rotation of the two tires. However, the existing technology has the disadvantages of time delay and inaccurate feedback for road feel feedback with steering wheel adjustment function. It cannot achieve the same steering feedback as traditional mechanical systems, which will increase the occurrence of misoperation to some extent.

[0004] Furthermore, in existing technologies, the steering wheel adjustment in both axes of the steer-by-wire system is usually achieved through independent mechanisms, resulting in a relatively small adjustment range.

[0005] Therefore, there is an urgent need to provide an electrically adjustable steer-by-wire device and its control method to achieve more accurate road feel feedback and a wider steering wheel adjustment range. Summary of the Invention

[0006] To address the above problems, the present invention provides an electrically adjustable steer-by-wire device and its control method.

[0007] A first aspect of the invention includes a steering wheel, and further includes: A steering column, the first end of which is connected to the steering wheel, and the second end of which is connected to the road feel simulation motor; The steering column includes a first axis defined by a sliding mechanism and having its sliding stroke axial direction defined therethrough, and a second axis defined by a rotating mechanism, wherein the second axis and the first axis are arranged in opposite directions. The steering wheel slides along the first axis to define a first space of movement, and rotates about the second axis to define a second space of movement. A first motor, connected to the steering column, provides drive for the steering wheel in the first active space via a sliding mechanism; The second motor, connected to the steering column, provides drive to the steering wheel in the second active space via a rotation mechanism.

[0008] In a preferred embodiment, the first motor is connected to the outer wall of the steering column via a first fixing member, and the drive end of the first motor is connected to a first lead screw. The first lead screw is limited by a first slider, and the first slider is fixedly connected to the steering column. The first lead screw drives the sliding mechanism to slide along the first axis.

[0009] In a preferred embodiment, the second motor is connected to the outer wall of the steering column via a second fixing member, and the driving end of the second motor is connected to one end of the second lead screw, while the other end of the second lead screw is connected to the rotating mechanism, driving the rotating mechanism to rotate around the second axis.

[0010] In a preferred embodiment, the steering column includes a first column and a second column, the first column being sleeved within the second column, and the first movable space being limited by the sliding stroke of the second column within the first column.

[0011] In a preferred embodiment, the rotating mechanism includes a second slider, a hinge, and a fixed support. The second slider is connected to the hinge via a second connector. The fixed support is rotatably connected to the outer wall of the second column. The hinge has a hinge point coaxial with the rotation point of the fixed support, which is the second axis. One end of the hinge is fixedly connected to the outer wall.

[0012] As a preferred embodiment, the length of the first lead screw is set to 160-200mm, and the sliding stroke length is less than or equal to the length of the first lead screw.

[0013] A second aspect of the present invention provides a control method for an electrically adjustable steer-by-wire device, comprising the following steps: S1. Obtain the time series parameter set when the motor adjusts the steering wheel, and preprocess it to obtain a parameter set including the actual contact area of ​​the steering column and the corresponding friction force change; S2. Determine the steering wheel's adjustment trajectory along the steering column axis relative to the previous time step at each moment corresponding to the time series parameter set, as well as the steering wheel's adjustment trajectory along the steering column axis. S3. Feedback signal to the device to keep the motor-driven steering wheel performing adjustment actions along the adjustment trajectory of the steering wheel along the steering column axis at the current time relative to the previous time and the adjustment trajectory of the steering wheel along the steering column axis. S4. Obtain the steering wheel attitude change coefficient when the motor adjusts along the steering column axis of the steering wheel relative to the previous time within the first time interval of the current time and multiple past time intervals. S5. Based on the adjustment trajectory of the steering wheel along the steering column axis and the change parameters of the steering wheel along the steering column axis at the current moment relative to the previous moment within the first time interval, determine the steering wheel attitude change coefficient at the current moment and multiple future moments within the second time interval. S6. Feed back the attitude change coefficient to a specified time in the future, and execute steering feedback control at the specified time.

[0014] Compared with the prior art, the present invention has the following advantages: This invention, through the arrangement of a first motor and a first lead screw, enables the first slider to have a sliding stroke corresponding to the first lead screw, thereby allowing the steering wheel to be adjusted in the axial direction within an adjustment range corresponding to the length of the first lead screw. Simultaneously, since the second motor of this invention drives the rotation of the entire steering column via a rotating mechanism, after the steering wheel is adjusted in the axial direction, it has a variable adjustment range around the axial direction, thus making the steering wheel adjustment range wider and more suitable for people of different heights.

[0015] This invention further obtains the mechanical response parameters of the first and second axes of the steering wheel, and dynamically adjusts the mechanical response parameters of the current stroke through the set contact elements. Using both as pre-adjustment parameters, the parameters of the first and second motors are adjusted in advance when future road conditions occur, so as to obtain accurate steering wheel feedback without delay and achieve more precise feedback control. Attached Figure Description

[0016] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0017] Figure 1 This is a structural schematic diagram of the electronically controlled steering device provided by the present invention from one perspective.

[0018] Among them, 1. Steering column; 2. First end; 3. Second end; 4. First motor; 5. Second motor; 6. First lead screw; 7. Second lead screw; 8. First slider; 9. Second slider; 10. First connector; 11. Second connector; 12. Hinge; 13. Fixed support; 14. Slider; 15. Slide groove; 16. First column; 17. Second column. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1

[0021] This disclosure provides an electrically adjustable steer-by-wire device, including a steering wheel (not shown in the figure), such as... Figure 1 As shown, it also includes a steering column 1, a first motor 4, and a second motor 5.

[0022] The steering column 1 of this embodiment has a first end 2 connected to a steering wheel and a second end 3 connected to a road feel simulation motor (not shown in the figure). The steering column 1 includes a first column 16 and a second column 17. The first column 16 is sleeved inside the second column 17, and the first column 16 slides within the second column 17 via a sliding mechanism. Specifically, in this embodiment, the steering column 1 has a first axis whose axial direction is defined by a sliding mechanism, and a second axis whose axial direction is defined by a rotation mechanism, and the second axis and the first axis are arranged in opposite directions.

[0023] The sliding mechanism of this embodiment includes a slider 14 and a groove 15. The slider 14 is fixedly connected to the outer tube wall of the first column 16, and the groove 15 is opened along the outer tube wall of the second column 17. The slider 14 slides in the groove 15 to allow the first column 16 to slide within the second column 17. In this embodiment, the length of the groove 15 is the length of the sliding stroke.

[0024] The steering wheel slides along the first axis to define the first range of motion, and rotates around the second axis to define the second range of motion.

[0025] The first motor 4 of this embodiment is connected to the steering column 1 and provides drive for the steering wheel in the first active space via a sliding mechanism. The second motor 5 of this embodiment is connected to the steering column 1 and provides drive for the steering wheel in the second active space via a sliding mechanism.

[0026] In a preferred embodiment of this disclosure, the first motor 4 is connected to the outer wall of the steering column 1 via a first fixing member, specifically to the outer wall of the second column 17. The drive end of the first motor 4 is connected to the first lead screw 6, and the first lead screw 6 is rotatably connected to the first slider 8. The first slider 8 is fixedly connected to the steering column 1 via a first connecting member 10. Specifically, the first slider 8 is connected to the outer wall of the first column 16. The first lead screw 6 drives the sliding mechanism to slide along the first axis. When the first lead screw 6 rotates, the first slider 8, in coordination with its rotation, is displaced along the length direction of the first lead screw 6, causing the first column 16 to slide along the second column 17 (that is, the slider slides along the groove 15).

[0027] In a preferred embodiment of this disclosure, the second motor 5 is connected to the outer wall of the steering column 1 via a second fixing member, and the driving end of the second motor 5 is connected to one end of the second lead screw 7, while the other end of the second lead screw 7 is connected to a rotating mechanism, driving the rotating mechanism to rotate around the second axis.

[0028] In this embodiment, the rotating mechanism includes a second slider 9, a hinge 12, and a fixed support 13. The second slider 9 is connected to the hinge 12 via a second connector 11. The fixed support 13 is rotatably connected to the outer wall of the second column 17. The hinge 12 has a hinge point coaxial with the rotation point of the fixed support 13, and this axis is the second axis. One end of the hinge 12 is fixedly connected to the outer wall. When one end of the fixed support 13 is fixed, the second lead screw 7 rotates under the drive of the second motor 5, causing the second slider 9 to move along the second lead screw 7. When the second slider 9 moves along the length direction, the linear motion of the second slider 9 will be converted into rotation along the hinge point by the first connecting member 10. At the same time, since the first lead screw 6, the first connecting member 10, the first slider 8 and the second column 17 of the steering column 1 are fixedly connected, when the second slider 9 moves, the first lead screw 6, the first connecting member 10 and the first slider 8 will also rotate synchronously. At this time, the limit displacement of the second end 3 is the second active space. Based on this, a wider adjustment range is formed when the second active space changes with the first active space.

[0029] As a preferred embodiment, the length of the second lead screw 7 is set to 160-200mm, and the sliding stroke length is less than or equal to the length of the first lead screw.

[0030] As a preferred embodiment, the contact surfaces of the first column 16 and the second column 17 are provided with multiple sets of continuously or spaced buffer members (not shown in the figure). Specifically, in this embodiment, the buffer members are provided on the contact surfaces of the first column 16 and the second column 17, spaced apart along the axial direction, and the friction coefficients of the buffer members at different axial positions are set to be different or the same. When the first column 16 moves to the corresponding position of the second column 17, the increased number of contacting buffer members leads to an increase in friction, thereby providing different resistance when the first column 16 slides along the second column 17. At the same time, the provision of buffer members can directly reduce the contact between the first column 16 and the second column 17, slow down the wear of the first column 16 and the second column 17, and facilitate maintenance and replacement.

[0031] The connection of the steering wheel in this embodiment is briefly described. The steering wheel is rotatably connected to the first end 2 of the steering column 1 relative to the first column 16. At least one angle sensor is provided in the steering column to sample the rotation angle of the steering wheel to realize steer-by-wire. In the art, the rotational connection of the steering wheel relative to the first column is a conventional technical means, which will not be described in detail here.

[0032] In this embodiment, the arrangement of the first motor 4 and the first lead screw 6 allows the first slider 8 to have a sliding stroke corresponding to the first lead screw 7, thereby enabling the steering wheel to be adjusted in the axial direction within an adjustment range corresponding to the length of the first lead screw 6. Simultaneously, since the second motor 5 in this embodiment drives the rotation of the entire steering column via a rotating mechanism, the change in position of the first end 2 after adjustment in the axial length direction of the steering wheel results in a variable adjustment range around the axial direction, thus making the steering wheel adjustment range more extensive and suitable for users of different heights.

[0033] Example 2 This disclosure provides a control method for an electronically controlled adjustable steering device, comprising the following steps: S1. Obtain the first time series parameter set when the road sense simulation motor feeds back to the road surface during the first time period.

[0034] In this embodiment, S1 obtains a first time series parameter set when the road feel simulation motor provides feedback on the road surface through a force sensor and a first attitude sensor. The timing characteristics of the first time series parameter set include a first timing characteristic and a second timing characteristic. The first timing characteristic is a series of consecutive moments or intervals at which the sensor performs sampling at a fixed adjustment position on the rotation trajectory of the steering wheel around the axis of the steering column 1 and / or the axial displacement trajectory of the steering wheel along the axis of the steering column 1 after a preset sampling period. The second timing characteristic is a series of consecutive moments or intervals at which the sensor performs sampling at different adjustment positions on the rotation trajectory of the steering wheel around the axis of the steering column 1 and / or the axial displacement trajectory of the steering wheel along the axis of the steering column 1 after a preset sampling period.

[0035] S2. Obtain the second time series parameter set when the steering wheel performs the first axis and second axis adjustment within the second time period.

[0036] The second time period is defined as the interval from the start of steering wheel adjustment to the end of adjustment. The first axis is the rotation axis of the steering wheel around the center of the steering column 1, and the second axis is the axial displacement axis of the steering wheel along the axis of the steering column 1. The second time series parameter set is collected by the second attitude sensor and position sensor, recording the rotation angle, axial displacement, and contact state parameters of the buffer component of the steering wheel during the second time period. It should be noted that there is a time mapping relationship between the first time period and the second time period. When the road-sensing simulation motor generates feedback at time t in the first time period, if the driver responds to the feedback, there is a corresponding response time t' in the second time period, where t' = t + Δt, and Δt is the driver's response delay, including perception delay and action execution delay; if the driver does not respond to the feedback, there is no response time corresponding to time t in the second time period, or the parameters in this part are redundant parameters.

[0037] S3. Determine the actual contact area and friction coefficient changes when the steering column performs adjustment in the second time series parameter set.

[0038] Specifically, in this embodiment, based on the contact state parameters of the buffer in the second time series parameter set, the dynamic change of the actual contact area between the steering column 1 and the buffer is calculated, and the change value of the friction coefficient is determined according to the material characteristics of the buffer. The change value of the friction coefficient reflects the friction difference of the buffer at different axial positions, so that the feedback force of the road feel simulation motor can accurately match the steering wheel position within a limited range.

[0039] S4. Determine the rotation trajectory of the steering wheel around the steering column axis relative to the previous time step at each moment corresponding to the first time series parameter set, as well as the axial displacement trajectory of the steering wheel along the steering column axis.

[0040] In this embodiment, the rotation trajectory is determined by the change in the steering wheel rotation angle, and the axial displacement trajectory is determined by the axial displacement of the steering wheel. The trajectory determination process takes into account the influence of the change in the friction coefficient of the buffer component on the adjustment path to ensure that the trajectory matches the actual adjustment behavior of the steering wheel.

[0041] S5. Feedback signal to the device to keep the motor-driven steering wheel performing adjustment actions along the rotation trajectory of the steering wheel around the steering column axis at the current moment relative to the previous moment and the axial displacement trajectory of the steering wheel along the steering column axis; at the same time, according to the friction coefficient of the buffer at the current position of the steering wheel, dynamically adjust the feedback force and direction of the road feel simulation motor to ensure that the feedback force and direction can be accurately transmitted to the steering wheel within the limited adjustment range of the road feel simulation motor.

[0042] S6. Obtain the road feel feedback coefficient when the road feel simulation motor feeds back to the road surface along the rotation trajectory and the axial displacement trajectory within the first time interval of the current moment and multiple past moments.

[0043] S7. Based on the change parameters of the rotation trajectory of the steering wheel around the steering column axis at the current moment relative to the previous moment and the axial displacement trajectory of the steering wheel along the steering column axis within the first time interval, determine the road feel feedback coefficient for the current moment and multiple future moments within the second time interval.

[0044] S8. Feed back the road feel feedback coefficient to a specified time at multiple future times, and execute steering feedback control at the specified time. In this embodiment, by dynamically adjusting the road feel feedback intensity and direction, synchronous adaptation with changes in steering wheel position is achieved, ensuring that road feel feedback is transmitted within a limited range.

[0045] As a preferred embodiment of S1, the preprocessing in this embodiment includes preprocessing of temporal features, including at least filtering redundant parameters and retaining parameters. When the device in this embodiment receives any feedback signal, it determines the retaining parameters by using the timestamp of the road surface feedback from the road sensing simulation motor. Specifically, it includes the following steps: When the first attitude sensor detects the start feedback command of the road-sensing simulated motor, it records the start time stamp of parameter acquisition. ; When the second attitude sensor detects an adjustment movement of the steering wheel, it records the end time stamp of parameter acquisition. ; Get to From all the parameters between them, the starting point of the second time series feature is determined. , to The parameters between these parameters are reserved. It should be noted that the driver's response to the road feel simulation motor is selective: not all road feel feedback will trigger the driver's adjustment action.

[0046] When the second attitude sensor does not detect steering wheel adjustment action, or When the preset threshold is reached, it indicates that the driver has not responded effectively to the road feel feedback, and all parameters corresponding to the feedback signal are defined as redundant parameters.

[0047] Redundant parameters mainly arise from two types of situations: (1) The intensity of the road feel feedback was lower than the driver’s perception threshold, and the driver failed to notice the change in feedback. (2) The driver's attention was distracted, and he failed to respond to road feedback in a timely manner. Eliminating redundant parameters can effectively reduce the amount of data processing and improve the accuracy of road feedback.

[0048] As a further preferred method for implementing S1 in this embodiment, a parameter modeling algorithm is used to generate a friction force change parameter model. In this embodiment, the parameter set includes at least the dynamic change information of the actual contact area of ​​the steering column 1 and the real-time quantitative information of the friction force, wherein the friction force change information and the change of contact area are as follows: When the steering wheel moves along the axis of steering column 1, the change in the compression of the buffer causes a dynamic change in the contact area. Changes in contact area cause response delay: If the contact area changes abruptly, the coefficient of friction drops rapidly, the road feel feedback is drastically reduced, and the driver's perception delay is shortened. If the contact area changes gradually, the coefficient of friction transitions smoothly, and the driver's perception delay is prolonged. This embodiment quantifies the change in friction coefficient using the Hertz contact model: ,in, for Constant friction coefficient As the reference friction coefficient, This represents the change in contact area. This is the initial contact area. This is the material coefficient of the buffer component.

[0049] It is particularly important to emphasize that changes in the actual contact area between the steering column 1 and the buffer directly lead to changes in driver response delay, specifically manifested as follows: When the steering wheel is adjusted quickly, the contact area changes abruptly (such as when the contact area decreases by more than 20% during a sharp turn), the coefficient of friction drops rapidly, the road feel feedback changes significantly, and the driver can quickly perceive and respond to it, with a response delay that is usually short (≤150ms). When the steering wheel is slowly adjusted, the contact area changes gradually (e.g., the contact area decreases by less than 5% when turning the steering wheel slowly), the coefficient of friction transitions smoothly, the change in road feel feedback is not obvious, the driver has difficulty perceiving it, and the response delay is usually long (≥300ms). When the change in contact area is at a critical state (such as a change in contact area of ​​about 10%), the change in the coefficient of friction causes the change in road feel feedback intensity to approach the driver's perception threshold, and the response delay shows large fluctuations (150-500ms). At this time, the system predicts the driver's possible response behavior through historical data.

[0050] In this embodiment, the parameter set includes at least the dynamic change information of the actual contact area of ​​the steering column 1 and the real-time quantitative information of the friction force. The friction force change information takes into account the difference in friction coefficient caused by the buffer set in Embodiment 1, so that the feedback force of the road feel simulation motor can accurately adapt to the steering wheel position within a limited range.

[0051] The rotation trajectory of the steering wheel around the axis of steering column 1 at the current moment relative to the previous moment is determined by acquiring the contact area and friction information of the steering wheel within the rotation adjustment range. Multiple segments with friction changes within a preset threshold are selected to determine this adjustment trajectory. The axial displacement trajectory of the steering wheel along the axis of steering column 1 is further determined based on the position of the steering wheel's rotation trajectory around the axis of steering column 1 at the current moment relative to the previous moment. Specifically, in this embodiment, after maintaining the centerline of the steering wheel adjustment at the middle position of the maximum adjustment range, the position of the axial displacement trajectory of the steering wheel along the axis of the steering column 1 is determined based on the current position of the rotation trajectory of the steering wheel around the axis of the steering column 1 relative to the previous moment. This achieves real-time adaptation of the motor to the steering wheel adjustment range. The specific calculation formula is as follows: ,in, This is the position of the axial centerline. The current rotation angle, This is the coupling coefficient; it increases when the contact area decreases, leading to a decrease in the friction coefficient. This value makes the axial displacement trajectory more sensitive.

[0052] Based on the correlation between the first and second time series parameter sets, the change in contact area in historical data is recorded. Corresponding actual response delay The mapping relationship; Establish a response delay prediction model: ( (Road condition information, driver's historical response characteristics); when a new change in contact area is detected, the system calculates the expected response delay using a predictive model. ; In road feel feedback control, advance Time-based feedback adjustment is implemented to compensate for driver response delays; For feedback signals identified as redundant parameters (i.e., situations where the driver does not respond), the system automatically reduces the priority of this type of feedback and appropriately weakens the intensity of such signals in subsequent feedback to avoid interfering with the driver's operation.

[0053] In practice, the response delay prediction model is implemented through the following steps: Record the change in contact area during each road feel feedback. coefficient of friction Traffic information and actual response delay ; Build using machine learning algorithms (such as random forests or neural networks) , Equal parameters and Nonlinear mapping relationship; When a new change in contact area is detected, the current parameters are input into the prediction model to obtain the expected response delay. ; In road feel feedback control, advance The timing-based feedback adjustment ensures that the road feel feedback reaches the expected state at the actual moment the driver responds.

[0054] This response delay prediction mechanism, combined with redundant parameter identification, allows the system to adjust road feel feedback in advance for predictable response behaviors, improving response synchronization. For redundant parameters (i.e., situations where the driver does not respond), the system automatically adjusts the feedback strategy to avoid excessive feedback interfering with the driver. By continuously learning the driver's response characteristics, the system continuously optimizes the prediction model to achieve personalized road feel feedback adaptation.

[0055] After determining the predicted response delay value, the road feel feedback coefficient is determined within a second time interval between the current moment and multiple past moments, based on the change parameters of the contact area information and friction force information of the steering wheel's rotation trajectory around the steering column 1 axis and the axial displacement trajectory of the steering wheel along the steering column 1 axis relative to the previous moment. Since the sensor can obtain the contact area information and friction force information of the steering wheel's rotation trajectory around the steering column 1 axis and the axial displacement trajectory of the steering wheel along the steering column 1 axis relative to the previous moment in advance, the advance adjustment time is calculated based on the predicted response delay value. At the advance adjustment time, a sequence of steering feedback control commands (including steering feedback control commands for multiple specified moments) is sent to ensure that when the device reaches the corresponding adjustment position at the specified moment, the road feel simulation motor has started and completed steering feedback control, thereby realizing continuous feedback control of the device during the adjustment process and ensuring that the steering wheel can achieve accurate road feel feedback and angle control at each adjustment position.

[0056] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented using electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods for each specific application to achieve the described functions, but such implementation should not be considered beyond the scope of the embodiments of this disclosure. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the described devices, apparatuses, and units can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0057] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, function, and operation of possible implementations of apparatus, methods, and computer program products according to embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different blocks may also occur in a different order than those disclosed in the description; sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. Each block in a block diagram and / or flowchart, and combinations of blocks in a block diagram and / or flowchart, can be implemented using a dedicated hardware-based device that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

Claims

1. An electrically adjustable steer-by-wire device, including a steering wheel, characterized in that, Also includes: A steering column, the first end of which is connected to the steering wheel, and the second end of which is connected to the road feel simulation motor; The steering column includes a first axis defined by a sliding mechanism and having its sliding stroke axial direction defined therethrough, and a second axis defined by a rotating mechanism, wherein the second axis and the first axis are arranged in opposite directions. The steering wheel slides along the first axis to define a first space of movement, and rotates about the second axis to define a second space of movement. A first motor, connected to the steering column, provides drive for the steering wheel in the first active space via a sliding mechanism; The second motor, connected to the steering column, provides drive to the steering wheel in the second active space via a rotation mechanism.

2. The electrically adjustable steer-by-wire device according to claim 1, characterized in that, The first motor is connected to the outer wall of the steering column via a first fixing member, and the drive end of the first motor is connected to a first lead screw. The first lead screw is limited by a first slider, and the first slider is fixedly connected to the steering column. The first lead screw drives the sliding mechanism to slide along the first axis.

3. The electrically adjustable steer-by-wire device according to claim 1, characterized in that, The second motor is connected to the outer wall of the steering column via the second fixing member, and the driving end of the second motor is connected to one end of the second lead screw, while the other end of the second lead screw is connected to the rotating mechanism, driving the rotating mechanism to rotate around the second axis.

4. The electrically adjustable steer-by-wire device according to claim 2, characterized in that, The steering column includes a first column and a second column, the first column being sleeved within the second column, and the first movable space being limited by the sliding stroke of the second column within the first column.

5. The electrically adjustable steer-by-wire device according to claim 3, characterized in that, The rotating mechanism includes a second slider, a hinge, and a fixed support. The second slider is connected to the hinge via a second connector. The fixed support is rotatably connected to the outer wall of the second column. The hinge has a hinge point coaxial with the rotation point of the fixed support, which is the second axis. One end of the hinge is fixedly connected to the outer wall.

6. The electrically adjustable steer-by-wire device according to claim 4, characterized in that, The length of the first lead screw is set to 160-200mm, and the sliding stroke length is less than or equal to the length of the first lead screw.

7. The electrically adjustable steer-by-wire device according to claim 4, characterized in that, The contact surfaces of the first column and the second column are provided with multiple sets of buffers that are arranged continuously or at intervals.

8. A control method for an electrically adjustable steer-by-wire device, characterized in that, Includes the following steps: S1. Obtain the first time series parameter set when the road sense simulation motor feeds back to the road surface during the first time period; S2. Obtain the second time series parameter set when the steering wheel performs the first axis and second axis adjustment within the second time period; S3. Determine the actual contact area and friction coefficient changes when the steering column performs adjustment in the second time series parameter set; S4. Determine the rotation trajectory of the steering wheel around the steering column axis relative to the previous time at each moment corresponding to the first time series parameter set, and the axial displacement trajectory of the steering wheel along the steering column axis. S5. Feedback signal to the device to keep the motor-driven steering wheel performing adjustment actions along the rotation trajectory of the steering wheel around the steering column axis at the current moment relative to the previous moment and the axial displacement trajectory of the steering wheel along the steering column axis; at the same time, dynamically adjust the feedback force and direction of the road feel simulation motor according to the friction coefficient of the buffer at the current position of the steering wheel. S6. Obtain the road feel feedback coefficient of the road feel simulation motor when it feeds back to the road surface along the rotation trajectory and the axial displacement trajectory within the first time interval of the current moment and multiple past moments; S7. Based on the change parameters of the rotation trajectory of the steering wheel around the steering column axis at the current moment relative to the previous moment and the axial displacement trajectory of the steering wheel along the steering column axis within the first time interval, determine the road feel feedback coefficient at the current moment and multiple future moments within the second time interval. S8. Feed back the road feel feedback coefficient to a specified time at multiple future times, and execute steering feedback control at the specified time.

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