Steer-by-wire system, end point limiting device and control method of road feeling simulator of steering-by-wire system and vehicle

Abstract

The invention discloses a steer-by-wire system, an endpoint limiting device of a road feeling simulator of the steer-by-wire system, a control method and a vehicle, and belongs to the technical field of steer-by-wire, the steer-by-wire system comprises a fixing frame of a hollow structure, and a first through hole and a second through hole are formed in the top surface and the bottom surface of the fixing frame respectively; the limiting nut is arranged in the fixing frame, a threaded hole of the limiting nut is opposite to the first through hole and the second through hole, and a vertical limiting groove penetrating through the top face and the bottom face of the limiting nut is formed in the peripheral face of the limiting nut; the limiting column is located in the limiting groove, the two ends of the limiting column are fixedly connected with the fixing frame, and the limiting nut is slidably connected with the limiting column; the two limiting blocks are symmetrically arranged on the two sides of the limiting nut respectively, the side faces, close to the limiting nut, of the limiting blocks are in a concave isosceles trapezoid shape, the two opposite ends of the limiting nut are located between the upper inclined face parts and the lower inclined face parts of the two limiting blocks respectively, and the limiting blocks are slidably connected with the fixing frame; the driving assembly is used for driving the limiting block to move. The limiting effect is improved, and the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of steer-by-wire, and in particular to an endpoint limiting device and a control method of a steer-by-wire system and a road feel simulator thereof, and a vehicle. Background Art

[0002] As a future trend in steering technology and a must-have for autonomous driving, steer-by-wire is being actively researched and developed by various OEMs and steering component companies. The endpoint limits of the road feel simulator for steer-by-wire are currently fixed. To achieve endpoint limits at different speeds, the road feel simulation motor must be able to provide a counter-torque greater than 30 Nm, which places high demands on the output torque of the road feel simulation motor. On the one hand, the higher requirements for the road feel simulation motor are more expensive, and on the other hand, the time required for the road feel simulation motor to provide a large counter-torque is limited, resulting in excess torque being wasted. During use, when the driver's operating force is too great, the endpoint limits implemented by the road feel simulation motor are prone to failure, resulting in poor limiting effect. Summary of the Invention

[0003] To address at least one aspect of the above-mentioned problems, the present invention provides a steer-by-wire system, an endpoint limiting device of a road feel simulator thereof, a control method, and a vehicle.

[0004] In the first aspect, the present application provides an endpoint limit device for a wire-controlled steering road feel simulator, comprising a fixing frame, a limit assembly, a drive assembly and a control component; the fixing frame is a hollow structure, comprising a top surface and a bottom surface parallel to the XY plane and arranged oppositely, and two side surfaces parallel to the YZ plane and arranged oppositely, and both side surfaces of the fixing frame are arranged between the top surface and the bottom surface; a first through hole and a second through hole are respectively provided at opposite positions of the middle area of ​​the top surface and the middle area of ​​the bottom surface of the fixing frame; a bearing is fixedly connected in the second through hole; the limit assembly is arranged in the fixing frame, and the limit assembly comprises a limit nut, a limit column and two limit blocks; the limit The nut is arranged in the fixing frame, and the threaded hole of the limiting nut is arranged opposite to the first through hole and the second through hole, and the threaded hole of the limiting nut matches the steering shaft of the wire-controlled steering, so that when the steering shaft of the wire-controlled steering passes through the first through hole and the threaded hole of the limiting nut in sequence and is connected to the bearing, the steering shaft is threadedly connected to the limiting nut; at least two limiting grooves extending along the Z direction and passing through the top and bottom surfaces thereof are provided on the outer circumference of the limiting nut, and the two limiting grooves are arranged opposite to each other; at least two limiting posts are provided, and the size of the limiting posts matches the size of the limiting grooves, and the limiting posts extend along the Z direction, and the two limiting posts are respectively located in the two limiting grooves, and the top of the limiting posts The bottom end is fixedly connected to the top and bottom surfaces of the fixing frame respectively, and the outer peripheral surface of the limit nut is slidably connected to the limit column along the Z direction through the limit groove; the two limit blocks are both arranged in the fixing frame and symmetrically arranged on both sides of the limit nut along the X direction and are respectively located between the limit nut and the side surfaces of the two fixing frames; the side of the limit block close to the limit nut is in the shape of an inward-concave isosceles trapezoid, and the side of the limit block close to the limit nut includes an upper inclined surface, a middle surface and a lower inclined surface, the middle surface is parallel to the YZ plane, the top and bottom end of the middle surface are respectively connected to the bottom end of the upper inclined surface and the top end of the lower inclined surface, and the angle between the upper inclined surface and the middle surface is the same as the angle between the lower inclined surface and the middle surface. The included angles of the intermediate surfaces are all obtuse angles; the opposite ends of the limit nut along the X direction are respectively located between the upper inclined surface and the lower inclined surface of the two limit blocks; the top surface and the bottom surface of the limit block are respectively connected to the top surface and the bottom surface of the fixing frame to slide toward or away from the limit nut along the X direction; two groups of drive components are provided, which are respectively arranged between the two side surfaces of the fixing frame and the two limit blocks, and are used to drive the two limit blocks to move toward or away from the limit nut along the X direction; the output end of the control component is respectively connected to the two groups of drive components, and the input end of the control component is used to be connected to the CAN line of the vehicle, and is used to control the operation of the drive component according to the vehicle speed signal on the CAN line of the vehicle.

[0005] Preferably, the connection between the top surface of the limit nut located between the upper inclined portion and the lower inclined portion of the limit block and the outer peripheral surface is a first inclined surface parallel to the upper inclined portion, and the connection between the bottom surface of the limit nut located between the upper inclined portion and the lower inclined portion of the limit block and the outer peripheral surface is a second inclined surface parallel to the lower inclined portion.

[0006] Preferably, the drive assembly includes a motor, a screw and a nut; the motor is fixedly connected to the side of the fixed frame; the nut is a ball nut, and the nut is coaxially fixedly connected to the rotor of the motor; the screw is a ball screw, which extends along the X direction, is passed through the nut, and cooperates with the nut; the first end of the screw is fixedly connected to the limit block.

[0007] Preferably, the control component includes two controllers, which are respectively fixedly connected to the motors in the two groups of drive assemblies or both are fixedly connected to the fixing frame. The two controllers are respectively electrically connected to the motors in the two groups of drive assemblies for controlling the operation of the motors; both controllers are connected to the vehicle CAN line.

[0008] Preferably, shock-absorbing pads are fixedly laid on the sides of the two limiting blocks close to the limiting nuts.

[0009] Preferably, sliders are fixedly connected to the top and bottom surfaces of the limit block; slide grooves extending along the X direction are provided on the top surface of the fixing frame at opposite sides of the first through hole, and slide grooves extending along the X direction are provided on the bottom surface of the fixing frame at opposite sides of the second through hole; the slider on the top surface of the limit block is located in the slide groove on the top surface of the fixing frame, and the slider on the bottom surface of the limit block is located in the slide groove on the bottom surface of the fixing frame, and the slider and the slide groove are slidably connected along the X direction.

[0010] Preferably, the fixing frame is a hollow rectangular tube structure surrounded by its top surface, bottom surface and two side surfaces, the top ends of the two side surfaces of the fixing frame are respectively fixedly connected to the two ends of the top surface of the fixing frame along the X direction, and the bottom ends of the two side surfaces of the fixing frame are respectively fixedly connected to the two ends of the bottom surface of the fixing frame along the X direction.

[0011] In the second aspect, the present application provides a control method for an endpoint limit device of a wire-controlled steering road feel simulator, which is used for a control component in an endpoint limit device of a wire-controlled steering road feel simulator as described above, and includes the following steps: receiving current vehicle speed information from the vehicle's CAN line; obtaining the current ideal transmission ratio based on the current vehicle speed information and a preset vehicle speed and ideal transmission ratio curve; calculating the current ideal position of the limit block based on the ideal transmission ratio, the design parameters of the current vehicle wire-controlled steering system, and the design parameters of the endpoint limit device of the current vehicle wire-controlled steering system road feel simulator; sending the current ideal position of the limit block to the drive component, so that the drive component drives the limit block to reach the current ideal position.

[0012] Preferably, when the limiting nut has a first inclined surface and a second inclined surface, the calculation formula for the current ideal position of the limiting block is:

[0013] ,

[0014] Where d represents the current ideal position of the limit block, and the position of the limit block at the minimum distance when the limit nut moves from the upper inclined surface to the lower inclined surface of the limit block is set to 0; i represents the ideal transmission ratio; α represents the maximum turning angle of the inner wheel of the current vehicle, and β represents the maximum turning angle of the outer wheel of the current vehicle. α and β are defined according to the vehicle type; k represents the pitch of the thread at the connection between the limit nut and the steering shaft; Represents the angle between the upper inclined surface and the middle surface of the endpoint limit device of the road feel simulator.

[0015] On the third aspect, the present application provides a wire-controlled steering system, including any of the above-mentioned endpoint limit devices for a wire-controlled steering road feel simulator, the steering shaft passes through the first through hole, the threaded hole of the limit nut and the bearing in sequence, and the steering shaft is threadedly connected to the limit nut; the fixed frame is fixedly connected to the deceleration mechanism of the wire-controlled steering system.

[0016] In a fourth aspect, the present application provides a vehicle comprising a steer-by-wire system as described above, wherein the control component is connected to the vehicle CAN line.

[0017] The steer-by-wire system and its endpoint limiting device and control method for a road feel simulator, as well as the vehicle, of the present invention have the following beneficial effects:

[0018] The present application designs a mechanical endpoint limit device whose endpoint limit changes with vehicle speed, that is, limit blocks with isosceles trapezoidal sides that are concave are designed on both sides of the limit nut. When the steering shaft of the linear steering drives the limit nut to move upward or downward, until the opposite ends of the limit nut abut against the upper inclined surface or lower inclined surface of the two limit blocks, the movement of the limit nut is restricted, thereby limiting the rotation of the steering shaft and playing the role of endpoint limit; the control part and the drive assembly dynamically adjust the position of the limit block according to the vehicle speed, that is, adjust the distance between the limit block and the limit nut in the x direction, thereby adjusting the movable distance of the limit nut between the upper inclined surface and the lower inclined surface of the limit block in the z direction, so that the endpoint limit changes with vehicle speed, which can reduce the requirements for the road feel simulation motor, reduce the parts cost of the wire-controlled steering road feel simulator, and improve the limiting effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To better understand the above and other objects, features, advantages, and functions of the present invention, reference may be made to the embodiments shown in the accompanying drawings. Like reference numerals in the accompanying drawings refer to like components. Those skilled in the art should understand that the accompanying drawings are intended to schematically illustrate preferred embodiments of the present invention and have no limiting effect on the scope of the present invention. The components in the drawings are not drawn to scale.

[0020] Figure 1A schematic structural diagram of an endpoint limiting device for a steer-by-wire road feel simulator according to an embodiment of the present invention is shown;

[0021] Figure 2 An exploded view of an endpoint limiting device for a steer-by-wire road feel simulator according to an embodiment of the present invention is shown;

[0022] Figure 3 A schematic diagram showing the operating principle of an endpoint limiting device for a steer-by-wire road feel simulator according to an embodiment of the present invention is shown;

[0023] Figure 4 A graph showing a preset vehicle speed and an ideal transmission ratio in a method for controlling an endpoint limiter of a steer-by-wire road feel simulator according to an embodiment of the present invention is shown.

[0024] Description of reference numerals:

[0025] 1. Fixing frame; 11. First through hole; 12. Second through hole; 13. Slide groove; 2. Bearing; 3. Limiting nut; 31. Threaded hole; 32. Limiting groove; 33. First inclined surface; 34. Second inclined surface; 4. Limiting column; 5. Limiting block; 51. Upper inclined surface; 52. Middle surface; 53. Lower inclined surface; 54. Slider; 55. Shock-absorbing pad; 61. Motor; 611. Fixing bolt; 62. Screw; 71. First buckle; 72. Second buckle; 73. Third buckle; 8. Controller; 9. Steering shaft. DETAILED DESCRIPTION

[0026] The following description of exemplary embodiments of the present disclosure is made in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding. These details should be considered as merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0027] As used herein, the term "including" and its variations represent open inclusion, i.e., "including but not limited to." Unless otherwise stated, the term "or" means "and / or." The term "based on" means "based at least in part on." The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment." The term "another embodiment" means "at least one additional embodiment." The terms "first," "second," etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0028] In order to at least partially solve one or more of the above problems and other potential problems, the embodiments of the present disclosure provide an endpoint limiting device for a steer-by-wire road feel simulator, such as Figures 1 to 3 As shown, it includes a fixing frame 1, a limiting component, a driving component and a control component.

[0029] like Figure 2 As shown, the fixing frame 1 is a hollow structure, comprising a top surface and a bottom surface that are parallel to the XY plane and opposite to each other, and two side surfaces that are parallel to the YZ plane and opposite to each other, with both side surfaces of the fixing frame 1 being disposed between the top surface and the bottom surface, wherein the X direction is the length direction of the fixing frame 1, the Y direction is the width direction of the fixing frame 1, and the Z direction is the height direction of the fixing frame 1. Specifically, the fixing frame 1 is a closed structure with a hollow interior, or a structure with a hollow interior and open ends along the Y direction. The cross-section of the fixing frame 1 along the XZ plane is a polygon such as a rectangle or an octagon, or the fixing frame 1 has two side surfaces that are parallel to each other and perpendicular to the top and bottom surfaces, and the connection between the top surface and the side surfaces and between the bottom surface and the side surfaces is a circular arc transition structure. Preferably, the fixing frame 1 is a hollow rectangular tube structure enclosed by its top surface, bottom surface, and two side surfaces, with the top ends of the two side surfaces of the fixing frame 1 being fixedly connected to the ends of the top surface of the fixing frame 1 along the X direction, and the bottom ends of the two side surfaces of the fixing frame 1 being fixedly connected to the ends of the bottom surface of the fixing frame 1 along the X direction. A first through hole 11 and a second through hole 12 are respectively provided at opposite positions of the middle area of ​​the top surface and the middle area of ​​the bottom surface of the fixing frame 1; a bearing 2 is fixedly connected to the second through hole 12. Specifically, the bearing 2 is preferably a needle bearing 2, and the bearing 2 is pressed into the second through hole 12 by an interference fit.

[0030] The limiting assembly is arranged in the fixing frame 1, and the limiting assembly includes a limiting nut 3, a limiting column 4 and two limiting blocks 5; the limiting nut 3 is arranged in the fixing frame 1, and the axial direction of the limiting nut 3 is the Z direction. The size of the limiting nut 3 along the Z direction is smaller than the distance between the top and bottom surfaces of the fixing frame 1, and the threaded hole 31 of the limiting nut 3 is arranged opposite to the first through hole 11 and the second through hole 12. The threaded hole 31 of the limiting nut 3 matches the steering shaft 9 of the wire-controlled steering, so that when the steering shaft 9 of the wire-controlled steering passes through the first through hole 11 and the threaded hole 31 of the limiting nut 3 and is connected to the bearing 2 in sequence, the steering shaft 9 is threadedly connected to the limiting nut 3. Preferably, a first buckle 71 is connected to the area where the steering shaft 9 extends out of the bearing 2 to prevent the steering shaft 9 from falling out; at least two limiting grooves 32 extending along the Z direction and passing through its top and bottom surfaces are provided on the outer peripheral surface of the limiting nut 3, and the two limiting grooves 32 are arranged opposite to each other.

[0031] At least two limiting columns 4 are provided, the size of the limiting columns 4 matches the size of the limiting groove 32, the limiting columns 4 extend along the Z direction, and the two limiting columns 4 are respectively located in the two limiting grooves 32. The top and bottom ends of the limiting columns 4 are respectively fixedly connected to the top and bottom surfaces of the fixing frame 1 through the second buckle 72, and the outer peripheral surface of the limiting nut 3 is slidably connected to the limiting column 4 along the Z direction through the limiting groove 32.

[0032] The two limit blocks 5 are both arranged in the fixing frame 1 and are symmetrically arranged on both sides of the limit nut 3 along the X direction and are respectively located between the limit nut 3 and the side surfaces of the two fixing frames 1; the side surface of the limit block 5 close to the limit nut 3 is in the shape of an isosceles trapezoid inwardly concave along the cross section of the XZ plane, and the side surface of the limit block 5 close to the limit nut 3 includes an upper inclined surface 51, an intermediate surface 52 and a lower inclined surface 53, the intermediate surface 52 is parallel to the YZ plane, and the top and bottom ends of the intermediate surface 52 are respectively connected to the bottom end of the upper inclined surface 51 and the top end of the lower inclined surface 53, and the angle between the upper inclined surface 51 and the intermediate surface 52 and the angle between the lower inclined surface 53 and the intermediate surface 52 are both obtuse angles, such as Figure 3 As shown in γ, preferably, the angle between the upper inclined surface 51 and the middle surface 52 is equal to the angle between the lower inclined surface 53 and the middle surface 52; in a preferred embodiment, shock-absorbing pads 55 are fixedly laid on the sides of the two limit blocks 5 close to the limit nut 3. The opposite ends of the limit nut 3 along the X direction are respectively located between the upper inclined surface 51 and the lower inclined surface 53 of the two limit blocks 5; the top surface and the bottom surface of the limit block 5 are respectively connected to the top surface and the bottom surface of the fixing frame 1 along the X direction so as to slide close to or away from the limit nut 3. Specifically, sliders 54 are fixedly connected to the top and bottom surfaces of the limit block 5; the top surface of the fixing frame 1 is provided with sliding grooves 13 extending along the X direction on both sides of the opposite sides of the first through hole 11, and the bottom surface of the fixing frame 1 is provided with sliding grooves 13 extending along the X direction on both sides of the opposite sides of the second through hole 12; the slider 54 on the top surface of the limit block 5 is located in the sliding groove 13 on the top surface of the fixing frame 1, and the slider 54 on the bottom surface of the limit block 5 is located in the sliding groove 13 on the bottom surface of the fixing frame 1, and the slider 54 is slidably connected to the sliding groove 13 along the X direction.

[0033] In a preferred embodiment, the connection between the top surface of the limit nut 3 located between the upper inclined portion 51 and the lower inclined portion 53 of the limit block 5 and the outer peripheral surface is a first inclined surface 33 parallel to the upper inclined portion 51, and the connection between the bottom surface of the limit nut 3 located between the upper inclined portion 51 and the lower inclined portion 53 of the limit block 5 and the outer peripheral surface is a second inclined surface 34 parallel to the lower inclined portion 53.

[0034] During the rotation of the steering shaft 9, the limit nut 3 is driven to move upward or downward along the Z direction. When the opposite ends of the limit nut 3 abut against the upper inclined surface 51 or the lower inclined surface 53 of the two limit blocks 5, the limit nut 3 stops moving upward or downward, restricting the axial shaft from continuing to rotate in the same direction, thereby realizing the end point limit function.

[0035] There are two groups of driving components, which are respectively arranged between the two side surfaces of the fixing frame 1 and the two limit blocks 5, and are used to drive the two limit blocks 5 to approach or move away from the limit nut 3 along the X direction, thereby adjusting the movable distance of the limit nut 3 between the upper inclined surface 51 and the lower inclined surface 53 of the limit block 5 in the Z direction to achieve the adjustment of the endpoint limit. Specifically, the drive assembly includes a motor 61, a screw 62 and a nut; the motor 61 is fixedly connected to the side of the fixing frame 1 by a fixing bolt 611; the nut is a ball nut, and the nut is coaxially fixedly connected to the rotor of the motor 61; the screw 62 is a ball screw 62, which extends along the X direction, is passed through the nut, and cooperates with the nut; the first end of the screw 62 is fixedly connected to the limit block 5 through the shoulder of the screw 62 and the third clip 73, and the second end of the screw 62 passes through the side of the fixing frame 1, the rotor of the motor 61 drives the nut to rotate, and the nut drives the screw 62 to make a linear motion along the X direction, thereby driving the limit block 5 to approach or move away from the limit nut 3 along the X direction.

[0036] In the process of designing the device of the present application, the screw 62 has a travel range of The calculation process is as follows:

[0037] because ,and ,but ,in, represents the ideal transmission ratio, Represents the total steering wheel angle, Represents the maximum turning angle of the inner wheel of the current vehicle, Represents the maximum turning angle of the outer wheels of the current vehicle, and Defined by vehicle type, is the total number of steering wheel turns.

[0038] like Figure 4 As shown, the curve relationship between vehicle speed and ideal transmission ratio is defined according to the vehicle model. and , so we can know and .

[0039] because ,in represents the distance that the limiting nut 3 moves from the upper inclined portion 51 to the lower inclined portion 53 of the limiting block 5, represents the pitch of the thread at the connection between the limit nut 3 and the steering shaft 9. Therefore, , , represents the maximum distance the limiting nut 3 moves from the upper inclined portion 51 to the lower inclined portion 53 of the limiting block 5, It represents the minimum distance that the limiting nut 3 moves from the upper inclined portion 51 to the lower inclined portion 53 of the limiting block 5 .

[0040] According to the geometric relationship, we can know , then the screw 62 stroke ,in Represents the included angle between the upper inclined surface 51 and the middle surface 52 in the endpoint limit device of the road feel simulator. Design the length of each chute.

[0041] The output end of the control unit is connected to each of the two drive assembly groups, while the input end of the control unit is connected to the vehicle's CAN line. This allows the drive assembly to be controlled based on the vehicle speed signal on the CAN line, thereby adjusting the end limit according to vehicle speed. Specifically, the control unit includes two controllers 8 , each of which is fixedly connected to the motors 61 in the two drive assembly groups or both are fixedly connected to the mounting bracket 1 . The two controllers 8 are electrically connected to the motors 61 in the two drive assembly groups for controlling the operation of the motors 61. Both controllers 8 are connected to the vehicle's CAN line for receiving the vehicle speed signal from the CAN line.

[0042] The present application also provides a control method for an endpoint limit device of a wire-controlled steering road feel simulator, which is used for a control component in any of the above-mentioned endpoint limit devices of a wire-controlled steering road feel simulator, comprising the following steps: receiving current vehicle speed information from a CAN line of a vehicle; obtaining a current ideal transmission ratio based on a preset vehicle speed and ideal transmission ratio curve according to the current vehicle speed information, specifically, the preset vehicle speed and ideal transmission ratio curve is defined according to the vehicle model, such as Figure 4 As shown, the horizontal axis is the vehicle speed and the vertical axis is the ideal transmission ratio; according to the ideal transmission ratio, the design parameters of the current vehicle's wire-controlled steering system, and the design parameters of the endpoint limit device of the current vehicle's wire-controlled steering system road feel simulator, the current ideal position of the limit block 5 is calculated; the current ideal position of the limit block 5 is sent to the drive component, so that the drive component drives the limit block 5 to the current ideal position.

[0043] In a preferred embodiment, when the limiting nut 3 has a first inclined surface 33 and a second inclined surface 34, the calculation formula for the current ideal position of the limiting block 5 is:

[0044] ,

[0045] Wherein, d represents the current ideal position of the limit block 5, and the position of the limit block 5 at the minimum distance when the limit nut 3 moves from the upper inclined portion 51 to the lower inclined portion 53 of the limit block 5 is set to 0; i represents the ideal transmission ratio; α represents the maximum turning angle of the inner wheel of the current vehicle, and β represents the maximum turning angle of the outer wheel of the current vehicle, and α and β are defined according to the vehicle type; k represents the pitch of the thread at the connection between the limit nut 3 and the steering shaft 9; represents the included angle between the upper inclined surface 51 and the middle surface 52 of the endpoint limit device of the road feel simulator, as shown in FIG. Figure 3 shown.

[0046] The present application also provides a wire-controlled steering system, including any of the above-mentioned endpoint limit devices for a wire-controlled steering road feel simulator, wherein the steering shaft 9 passes through the first through hole 11 and the threaded hole 31 of the limit nut 3 in sequence and is connected to the bearing 2, and the steering shaft 9 is threadedly connected to the limit nut 3. Preferably, the steering shaft 9 passes through the bearing 2, and is connected to a first buckle 71 in the area where the steering shaft 9 extends out of the bearing 2 to prevent the steering shaft 9 from falling out; the fixing frame 1 is fixedly connected to the deceleration mechanism of the wire-controlled steering system.

[0047] The present application also provides a vehicle, including the above-mentioned wire-controlled steering system, wherein the control component is connected to the vehicle CAN line, specifically, both controllers 8 are connected to the vehicle CAN line.

[0048] While various embodiments of the present disclosure have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand this document.

Claims

1. An endpoint limiter for a steer-by-wire road feel simulator, characterized by: The invention comprises a fixing frame, a limiting assembly, a driving assembly and a control component; the fixing frame is a hollow structure, and a first through hole and a second through hole are respectively provided at opposite positions of the top surface and the bottom surface thereof; a bearing is fixedly connected in the second through hole; the limiting assembly is arranged in the fixing frame, and the limiting assembly comprises a limiting nut, a limiting column and two limiting blocks; the threaded hole of the limiting nut is arranged opposite to the first through hole and the second through hole, and matches the steering shaft of the wire-controlled steering; a limiting groove is provided on the outer circumference of the limiting nut, extending along the Z direction and passing through the top and bottom surfaces thereof; the limiting column is located in the limiting groove, and the two ends of the limiting column are respectively fixed to the top and bottom surfaces of the fixing frame, and the limiting nut is slidably connected to the limiting column along the Z direction through the limiting groove; the two limiting blocks are symmetrically arranged in the limiting The limiting nuts are on both sides along the X direction; the side of the limiting block close to the limiting nut is in the shape of an inward-concave isosceles trapezoid, which includes an upper inclined surface, a middle surface and a lower inclined surface, the middle surface is parallel to the YZ plane, and the angle between the upper inclined surface and the middle surface and the angle between the lower inclined surface and the middle surface are both obtuse angles; the two ends of the limiting nut along the X direction are respectively located between the upper inclined surface and the lower inclined surface of the two limiting blocks; the top surface and the bottom surface of the limiting block are respectively connected to the top surface and the bottom surface of the fixing frame in a sliding direction close to or away from the limiting nut; the driving assembly is used to drive the two limiting blocks to approach or move away from the limiting nut along the X direction; the control component is connected to the driving assembly and the vehicle CAN line, and is used to control the operation of the driving assembly according to the vehicle speed signal of the vehicle CAN line.

2. The endpoint limit device for a steer-by-wire road feel simulator according to claim 1, characterized in that: The connection between the top surface of the limiting nut located between the upper inclined portion and the lower inclined portion of the limiting block and the outer peripheral surface is a first inclined surface parallel to the upper inclined portion, and the connection between the bottom surface of the limiting nut located between the upper inclined portion and the lower inclined portion of the limiting block and the outer peripheral surface is a second inclined surface parallel to the lower inclined portion.

3. The endpoint limit device for a steer-by-wire road feel simulator according to claim 1, characterized in that: The drive assembly includes a motor, a screw and a nut; the motor is fixedly connected to the side of the fixed frame; the nut is a ball nut, and the nut is coaxially fixedly connected to the rotor of the motor; the screw is a ball screw, which extends along the X direction, passes through the nut, and cooperates with the nut; the first end of the screw is fixedly connected to the limit block.

4. The endpoint limit device for a steer-by-wire road feel simulator according to claim 1, characterized in that: Shock-absorbing pads are fixedly laid on the sides of the two limiting blocks close to the limiting nuts.

5. The endpoint limit device for a steer-by-wire road feel simulator according to claim 1, characterized in that: Slide blocks are fixedly connected to the top and bottom surfaces of the limit block; slide grooves extending along the X direction are provided on the top surface of the fixing frame on opposite sides of the first through hole, and slide grooves extending along the X direction are provided on the bottom surface of the fixing frame on opposite sides of the second through hole; the slide block on the top surface of the limit block is located in the slide groove on the top surface of the fixing frame, and the slide block on the bottom surface of the limit block is located in the slide groove on the bottom surface of the fixing frame, and the slide block and the slide groove are slidably connected along the X direction.

6. The endpoint limit device for a steer-by-wire road feel simulator according to claim 1, characterized in that: The fixing frame is a hollow rectangular tube structure surrounded by its top surface, bottom surface and two side surfaces. The top ends of the two side surfaces of the fixing frame are respectively fixedly connected to the two ends of the top surface of the fixing frame along the X direction, and the bottom ends of the two side surfaces of the fixing frame are respectively fixedly connected to the two ends of the bottom surface of the fixing frame along the X direction.

7. A control method for an endpoint limiter for a steer-by-wire road feel simulator, used as a control element in the endpoint limiter for a steer-by-wire road feel simulator according to any one of claims 1 to 6, characterized in that: The following steps are involved: Receive current vehicle speed information from the vehicle's CAN line; According to the current vehicle speed information, based on the preset vehicle speed and ideal transmission ratio curve, the current ideal transmission ratio is obtained; Calculate the current ideal position of the limit block based on the ideal transmission ratio, the design parameters of the current vehicle's steer-by-wire system, and the design parameters of the endpoint limit device of the current vehicle's steer-by-wire system road feel simulator; The current ideal position of the limit block is sent to the driving component, so that the driving component drives the limit block to reach the current ideal position.

8. The control method for the endpoint limit device of a steer-by-wire road feel simulator according to claim 7, characterized in that: When the limiting nut has a first inclined surface and a second inclined surface, the calculation formula for the current ideal position of the limiting block is: ， Where d represents the current ideal position of the limit block, and the position of the limit block at the minimum distance when the limit nut moves from the upper inclined surface to the lower inclined surface of the limit block is set to 0; i represents the ideal transmission ratio; α represents the maximum turning angle of the inner wheel of the current vehicle, and β represents the maximum turning angle of the outer wheel of the current vehicle. α and β are defined according to the vehicle type; k represents the pitch of the thread at the connection between the limit nut and the steering shaft; Represents the angle between the upper inclined surface and the middle surface of the endpoint limit device of the road feel simulator.

9. A steer-by-wire system, characterized in that: It comprises an endpoint limit device for a wire-controlled steering road feel simulator as described in any one of claims 1 to 6, wherein the steering shaft passes through the first through hole and the threaded hole of the limit nut in sequence and is connected to the bearing, and the steering shaft is threadedly connected to the limit nut; and the fixing frame is fixedly connected to the deceleration mechanism of the wire-controlled steering system.

10. A vehicle, characterized in that: Including a wire-controlled steering system as described in claim 9, the control component is connected to the vehicle CAN line.

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