Steer-by-wire steering feel simulator, vehicle, and steering wheel resistance control method

Abstract

The present application provides a steer-by-wire steering feel simulator, a vehicle, and a steering wheel resistance control method. The steer-by-wire steering feel simulator comprises a housing, a connecting shaft, and a control circuit; an accommodating cavity is provided inside the housing, the accommodating cavity is filled with a magnetorheological fluid, and a limiting structure is provided in the accommodating cavity; one end of the connecting shaft is connected to a steering wheel, the other end of the connecting shaft is placed in the accommodating cavity and is provided with a blade, and the connecting shaft is capable of rotating to drive the blade to agitate the magnetorheological fluid; the control circuit is capable of controlling the resistance of the magnetorheological fluid to the rotation of the blade, and when the magnetorheological fluid is solidified, the solidified magnetorheological fluid works in conjunction with the limiting structure to limit the rotation of the blade relative to the housing.

Description

Steer-by-wire feel simulator, vehicle and steering wheel resistance control methods Cross-references to related applications

[0001] This application claims priority to Chinese patent application No. 202510071556.8, filed on January 16, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to, but is not limited to, the field of vehicle steering device technology, and particularly to a steer-by-wire feel simulator and a method for controlling vehicle and steering wheel resistance. Background Technology

[0003] The vehicle uses steer-by-wire technology to control its direction. Steer-by-wire technology eliminates the mechanical connection between the steering wheel and the steering wheels, freeing it from the limitations of mechanical components and using electrical energy to achieve steering. Summary of the Invention

[0004] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0005] At least one embodiment of this application provides a steer-by-wire feel simulator, a vehicle, and a steering wheel resistance control method.

[0006] A first aspect of this application provides a steer-by-wire simulator, including a housing, a connecting shaft, and a control circuit. The housing has an internal cavity filled with magnetorheological fluid, and a limiting structure is provided within the cavity. One end of the connecting shaft is connected to a steering wheel, and the other end of the connecting shaft is placed within the cavity and has a fan blade. The connecting shaft is rotatable to drive the fan blade to agitate the magnetorheological fluid. The control circuit is configured to control the resistance of the magnetorheological fluid to the rotation of the fan blade, and the magnetorheological fluid, when solidified, cooperates with the limiting structure to restrict the rotation of the fan blade relative to the housing.

[0007] Optionally, a hollow upper cylinder is connected to the housing, and the upper cylinder is sleeved on the outside of the connecting shaft.

[0008] Optionally, the upper column includes a base and a bracket. The base is connected to the housing to form a placement space between the base and the housing, and the control circuit is disposed in the placement space. The bracket is connected to the side of the base facing away from the housing, and the end of the connecting shaft away from the receiving cavity passes through the base and extends into the interior of the bracket.

[0009] Optionally, the upper cylinder is provided with a positioning notch, and the housing is provided with a positioning protrusion, the positioning protrusion being inserted into the positioning notch.

[0010] Optionally, a bearing is provided between the housing and the connecting shaft, and the connecting shaft is sealed to the inner ring of the bearing.

[0011] Optionally, the connecting shaft includes a mounting base and a main shaft portion, one side of the mounting base is connected to the main shaft portion, and the other side of the mounting base is connected to the fan blade; the mounting base is placed on the inner ring of the bearing and drives the inner ring to rotate, and the mounting base is sealed to the inner ring of the bearing.

[0012] Optionally, the control circuit includes a coil and an electronic control unit, the coil being sleeved on the connecting shaft, and the electronic control unit being electrically connected to the coil so that the electronic control unit controls the current passing through the coil.

[0013] Optionally, the fan blades extend radially along the connecting shaft.

[0014] Optionally, the limiting structure includes a plurality of positioning grooves, which are radially disposed on the inner wall of the receiving cavity along the connecting shaft, and are spaced apart circumferentially along the receiving cavity.

[0015] Optionally, the housing includes a box body and a cover plate, the box body has an interior space, and one side of the box body has a box opening, the cover plate covers the box opening so that the cover plate and the box body together form the receiving cavity.

[0016] A second aspect of this application provides a vehicle including a steer-by-wire feel simulator as described in any of the preceding claims.

[0017] A third aspect of this application provides a steering wheel resistance control method applied to a steer-by-wire feel simulator as described in any of the preceding claims. The method includes: determining the resistance to steering wheel rotation based on the rotation angle of the steering wheel relative to an initial position; increasing the current intensity in the control circuit when it is necessary to increase the resistance to steering wheel rotation; decreasing the current intensity in the control circuit when it is necessary to decrease the resistance to steering wheel rotation; and increasing the current in the control circuit above a set current when it is necessary to limit the steering wheel's continued rotation after rotating it by a set angle, so as to solidify the magnetorheological fluid.

[0018] Optionally, when it is necessary to limit the continued rotation of the steering wheel when it is rotated to a set angle, the current in the control circuit is increased to a set current or higher to solidify the magnetorheological fluid. This includes: when the steering wheel is rotated to a set number of revolutions and the direction of force on the steering wheel is in the same direction as the rotation direction of the steering wheel, the current in the control circuit is increased to a set current or higher to solidify the magnetorheological fluid.

[0019] Optionally, the method further includes: when the steering wheel is rotated to the set number of revolutions and the direction of force on the steering wheel is opposite to the direction of rotation of the steering wheel, reducing the current in the control circuit so that the steering wheel can rotate toward the initial position.

[0020] This application provides a steer-by-wire feel simulator, a vehicle, and a steering wheel resistance control method. The steer-by-wire feel simulator includes a housing, a connecting shaft, and a control circuit. The housing has an internal cavity filled with magnetorheological fluid and a limiting structure within it. One end of the connecting shaft connects to the steering wheel, and the other end is placed within the cavity and has blades. The connecting shaft can rotate to drive the blades to agitate the magnetorheological fluid. The control circuit is configured to control the resistance of the magnetorheological fluid to the rotation of the blades. When the magnetorheological fluid solidifies, it cooperates with the limiting structure to restrict the rotation of the blades relative to the housing. By adjusting the current in the control circuit, the fluidity of the magnetorheological fluid can be adjusted, thereby changing the force required for the driver to turn the steering wheel, resulting in different feel when the driver turns the steering wheel. The control circuit solidifies the magnetorheological fluid, restricting the rotation of the blades and preventing the steering wheel from continuing to rotate, thus limiting the number of steering wheel rotations. By coordinating the control circuit, connecting shaft, magnetorheological fluid in the cavity, and limiting structure, the steer-by-wire feel simulator can conveniently change the steering wheel rotation resistance to simulate the feel, and also limit the number of steering wheel rotations. This eliminates the need for a motor with a reduction mechanism and a limiting device on the steering wheel to restrict the number of steering wheel rotations, simplifying the structure of the vehicle steering system and improving vehicle assembly efficiency.

[0021] After reading and understanding the accompanying diagrams and detailed descriptions, the other aspects can be understood. Attached Figure Description

[0022] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0023] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0024] Figure 1 is a schematic diagram of the steer-by-wire feel simulator described in an embodiment of this application.

[0025] Figure 2 is a cross-sectional schematic diagram of the steer-by-wire feel simulator described in an embodiment of this application.

[0026] Figure 3 is a cross-sectional view of the housing described in an embodiment of this application.

[0027] Figure 4 is a partial exploded view of the steer-by-wire feel simulator described in the embodiment of this application.

[0028] Figure 5 is a flowchart illustrating the steering wheel resistance control method described in an embodiment of this application.

[0029] Explanation of reference numerals in the attached drawings: 1. Housing; 11. Receiving cavity; 12. Mounting hole; 13. Limiting structure; 131. Positioning groove; 14. Bearing; 15. Positioning protrusion; 16. Cover plate; 17. Box body; 2. Connecting shaft; 21. Main shaft part; 22. Mounting seat; 23. Sealing ring; 3. Control circuit; 31. Coil; 32. Electronic control unit; 4. Fan blade; 5. Upper column cylinder; 51. Base; 511. Positioning notch; 52. Bracket; 53. Placement space. Detailed Implementation

[0030] To better understand the above-mentioned objectives, features, and advantages of this application, the solution of this application will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0031] Numerous specific details are set forth in the following description to provide a thorough understanding of this application, but this application may also be implemented in other ways different from those described herein. The embodiments in the specification are only a part of the embodiments of this application, and not all of them.

[0032] In steer-by-wire technology, there is no rigid connection between the steering wheel and the steering wheels. This means that the resistance to steering wheel rotation cannot reflect changes in rotation, meaning the driver cannot judge the vehicle's steering status by the feel of turning the steering wheel. Therefore, steer-by-wire systems typically incorporate a motor on the steering wheel. This motor, in conjunction with a reduction mechanism, alters the resistance to steering wheel rotation to simulate steering feel. Furthermore, to limit the number of steering wheel rotations, a limiting device is required on the steering wheel's shaft. This limiting device usually includes a rack and pinion. Rotation of the shaft causes relative movement of the rack and pinion; limiting the distance the rack travels limits the number of steering wheel rotations.

[0033] However, the motor and limit device on the steering wheel occupy a lot of space and make the overall structure of the steering wheel and steer-by-wire system complicated, affecting the assembly efficiency of the vehicle's steering system.

[0034] In view of this, at least one embodiment of this application provides a steer-by-wire feel simulator, a vehicle and a steering wheel resistance control method.

[0035] As shown in Figures 1 to 4, a first aspect of this application provides a steer-by-wire simulator, including a housing 1, a connecting shaft 2, and a control circuit 3. The housing 1 has an internal cavity 11 filled with magnetorheological fluid, and a limiting structure 13 is provided within the cavity 11. One end of the connecting shaft 2 is connected to a steering wheel, and the other end of the connecting shaft 2 is placed within the cavity 11 and has a fan blade 4. The connecting shaft 2 can rotate to drive the fan blade 4 to agitate the magnetorheological fluid. The control circuit 3 is configured to control the resistance of the magnetorheological fluid to the rotation of the fan blade 4, and when the magnetorheological fluid is solidified, it cooperates with the limiting structure 13 to restrict the rotation of the fan blade 4 relative to the housing 1.

[0036] Specifically, the interior of the housing 1 is hollow, forming a receiving cavity 11. The receiving cavity 11 can be a cylindrical cavity or a cavity of other shapes. The housing 1 has a through hole communicating with the receiving cavity 11 as a mounting hole 12, and the connecting shaft 2 passes through the mounting hole 12, with a sealed connection between the connecting shaft 2 and the inner wall of the mounting hole 12. In some embodiments, the mounting hole 12 can be a circular hole, with the outer circumferential surface of the connecting shaft 2 abutting against the inner wall of the mounting hole 12, so as to seal the connection between the connecting shaft 2 and the inner wall of the mounting hole 12, thereby preventing the magnetorheological fluid in the receiving cavity 11 from leaking through the mounting hole 12.

[0037] In other embodiments, a bearing 14 may be provided in the mounting hole 12, with the outer ring of the bearing 14 being sealed to the inner wall of the mounting hole 12. The connecting shaft 2 is provided inside the inner ring of the bearing 14 and is sealed to the inner ring of the bearing 14. When the inner ring of the bearing 14 rotates relative to the outer ring, the connecting shaft 2 can rotate relative to the housing 1.

[0038] The aforementioned magnetorheological fluid exhibits low-viscosity Newtonian fluid characteristics under zero magnetic field conditions, while exhibiting high viscosity and low flowability under a strong magnetic field. There is a correlation between the viscosity of the magnetorheological fluid and the magnetic flux; the higher the magnetic flux, the lower the flowability. Magnetorheological fluids can transform from freely flowing liquids to semi-solids or even solids within milliseconds, exhibiting strong controllable rheological properties. The transformation process of magnetorheological fluids is instantaneous, and they also possess low energy consumption, leading to some applications in automotive steering systems.

[0039] The aforementioned steering wheel has a drive shaft, and rotating the steering wheel will drive the drive shaft to rotate. When the drive shaft is connected to the connecting shaft 2, rotating the drive shaft of the steering wheel will drive the connecting shaft 2 to rotate synchronously. One end of the connecting shaft 2 is provided with a fan blade 4 inside the receiving cavity 11, and the fan blade 4 is in contact with the magnetorheological fluid inside the receiving cavity 11. In some embodiments, the magnetorheological fluid can fill the receiving cavity 11, so that the magnetorheological fluid can envelop the fan blade 4. In other embodiments, there can be a space between the magnetorheological fluid and the receiving cavity 11, and the fan blade 4 is always completely located inside the magnetorheological fluid, and the magnetorheological fluid and the limiting structure 13 are always in contact.

[0040] When the connecting shaft 2 rotates, the fan blade 4 rotates within the magnetorheological fluid in the receiving cavity 11. Without an external magnetic field, the magnetorheological fluid has low viscosity, resulting in low resistance to the rotation of the fan blade 4. When an external magnetic field is applied to the magnetorheological fluid, the resistance to rotation increases. When the magnetic field strength applied to the magnetorheological fluid exceeds a certain value, the magnetorheological fluid solidifies and transforms into a solid structure. The solidified magnetorheological fluid can encapsulate the fan blade 4, forming a bulk structure with the solidified fluid. Because the magnetorheological fluid fills the receiving cavity 11, it maintains constant contact with the limiting structure 13. The bulk structure formed by the fan blade 4 and the magnetorheological fluid is then engaged with the limiting structure 13, restricting its rotation within the receiving cavity 11. In this way, after the magnetorheological fluid solidifies, it is engaged with the limiting structure 13 to restrict the fan blade 4 from rotating in the receiving cavity 11, so that the connecting shaft 2 cannot rotate relative to the housing 1 after the magnetorheological fluid solidifies, thereby achieving the effect of restricting the steering wheel from continuing to rotate.

[0041] The aforementioned control circuit 3 can be mounted on the housing 1 or on the connecting shaft 2. When the control circuit 3 is energized, it generates a magnetic field. An increase in the current within the control circuit 3 increases the strength of the generated magnetic field; a decrease in the current within the control circuit 3 decreases the strength of the generated magnetic field. The magnetic field generated by the control circuit 3 passes through the housing 1 and is applied to the magnetorheological fluid within the receiving cavity 11. Adjusting the magnitude of the current within the control circuit 3 controls the strength of the magnetic field applied to the magnetorheological fluid, thereby adjusting the fluidity of the magnetorheological fluid.

[0042] The aforementioned limiting structure 13 can be a groove or a protrusion on the inner wall of the receiving cavity 11. The receiving cavity 11 is filled with magnetorheological fluid, allowing the fluid to fill the groove or enclose the protrusion. When the magnetorheological fluid can flow, the limiting structure 13 does not restrict its flow; when the magnetorheological fluid solidifies, the solid structure formed by the fluid will insert into the groove or engage with the protrusion, preventing the solidified fluid from rotating within the receiving cavity 11.

[0043] The aforementioned housing 1 can be connected to the vehicle's internal frame structure or to a bracket inside the vehicle used to mount the steering wheel, preventing the housing 1 from rotating inside the vehicle. When the magnetorheological fluid solidifies and cannot rotate within the receiving cavity 11, the fan blade 4 is encased in the solidified magnetorheological fluid, preventing the connecting shaft 2 from rotating relative to the housing 1. At this time, the rotation of the steering wheel connected to the connecting shaft 2 is restricted; that is, after the steering wheel rotates a set number of times, the current in the control circuit 3 will increase above the set value, causing the magnetorheological fluid to solidify and restricting further rotation of the steering wheel.

[0044] In practical use, the steer-by-wire feel simulator provided in this application embodiment connects the connecting shaft 2 to the steering wheel. When the steering wheel rotates, it drives the connecting shaft 2 to rotate, which in turn drives the fan blade 4 to rotate within the receiving cavity 11, thus agitating the magnetorheological fluid. Using the steering wheel position during straight-line driving as the initial position, the current in the control circuit 3 is adjusted according to the rotation angle of the steering wheel relative to the initial position. The magnetic field generated by the control circuit 3 is applied to the magnetorheological fluid, changing its fluidity and thus altering the force required for the driver to turn the steering wheel, thereby changing the feel of the steering wheel and simulating the steering feel operation.

[0045] The greater the current in control circuit 3, the lower the fluidity of the magnetorheological fluid, and the greater the resistance to steering wheel rotation. When the steering wheel is rotated a set number of times, for example, one and a half rotations, which is equivalent to the steering wheel rotating 540° in one direction relative to its initial position, the current in control circuit 3 increases to a value greater than the set value, causing the magnetorheological fluid to solidify and preventing the fan blades 4 from rotating within the receiving cavity 11. At this point, the steering wheel can no longer rotate.

[0046] The steer-by-wire simulator provided in this embodiment includes a housing 1, a connecting shaft 2, and a control circuit 3. The housing 1 has an internal cavity 11 filled with magnetorheological fluid, and a limiting structure 13 is provided within the cavity 11. One end of the connecting shaft 2 is connected to a steering wheel, and the other end is placed within the cavity 11 and has a fan blade 4. The connecting shaft 2 can rotate to drive the fan blade 4 to agitate the magnetorheological fluid. The control circuit 3 is configured to control the resistance of the magnetorheological fluid to the rotation of the fan blade 4. When the magnetorheological fluid is solidified, it cooperates with the limiting structure 13 to restrict the rotation of the fan blade 4 relative to the housing 1. By adjusting the current in the control circuit 3, the fluidity of the magnetorheological fluid can be adjusted, thereby changing the force required for the driver to turn the steering wheel, resulting in different steering wheel feel. The control circuit 3 solidifies the magnetorheological fluid, restricting the rotation of the fan blade 4 and preventing the steering wheel from continuing to rotate, thus limiting the number of steering wheel rotations. Through the cooperation of the control circuit 3, the connecting shaft 2, the magnetorheological fluid in the cavity 11, and the limiting structure 13, the steer-by-wire feel simulator can conveniently change the steering wheel rotation resistance to simulate the feel, and can also limit the number of steering wheel rotations. This eliminates the need to install a motor with a reduction mechanism and a limiting device on the steering wheel to limit the number of steering wheel rotations, thus simplifying the structure of the vehicle steering system and improving vehicle assembly efficiency.

[0047] As shown in Figures 1, 2, and 4, in some embodiments, a hollow upper cylinder 5 is connected to the housing 1, and the upper cylinder 5 is sleeved on the outside of the connecting shaft 2. This arrangement allows the upper cylinder 5 to protect the connecting shaft 2.

[0048] Specifically, the upper column cylinder 5 can be a hollow cylindrical structure. The upper column cylinder 5 is located on the side of the housing 1 where the mounting hole 12 is located, and the mounting hole 12 is on the inner side of the upper column cylinder 5. The upper column cylinder 5 extends axially along the mounting hole 12. The portion of the connecting shaft 2 outside the housing 1 is inside the upper column cylinder 5, thus protecting the connecting shaft 2. The inner side of the upper column cylinder 5 near the housing 1 can fit against the outer circumferential surface of the connecting shaft 2, giving the upper column cylinder 5 a positioning effect on the connecting shaft 2. The drive shaft of the steering wheel extends into the upper column cylinder 5 and connects to the connecting shaft 2.

[0049] As shown in Figures 1, 2, and 4, in some embodiments, the upper column 5 includes a base 51 and a bracket 52. The base 51 is connected to the housing 1 to form a placement space 53 between the base 51 and the housing 1, and the control circuit 3 is disposed in the placement space 53. The bracket 52 is connected to the side of the base 51 facing away from the housing 1, and the end of the connecting shaft 2 away from the receiving cavity 11 passes through the base 51 and extends into the interior of the bracket 52.

[0050] With this configuration, the placement space 53 formed between the base 51 and the housing 1 can protect the control circuit 3, preventing external collisions or foreign objects from causing the control circuit 3 to break down. The bracket 52 can protect the connecting shaft 2, and the connecting shaft 2 passes through the base 51, so that the base 51 can support the connecting shaft 2, improving the stability of the connecting shaft 2 located outside the housing 1 and preventing the connecting shaft 2 from shaking in the radial direction.

[0051] Specifically, in some embodiments, the base 51 may include a plate and a skirt. The skirt is connected to the edge of the plate and is arranged around the center of the plate. The plate and the side of the housing 1 with the mounting hole 12 are arranged opposite to each other and connected to each other. The skirt is connected to the housing 1, so that the plate, the skirt and the housing 1 together form a placement space 53. The control circuit 3 is arranged in the placement space 53.

[0052] In other embodiments, the base 51 may also be configured as a block structure. The interior of the base 51 is hollow, forming a placement space 53. Two through holes are formed on opposite sides of the block structure, and the two through holes are coaxially arranged with the mounting hole 12. The portion of the connecting shaft 2 outside the housing 1 passes through the two through holes of the base 51.

[0053] A portion of the aforementioned connecting shaft 2 is located in the placement space 53. The control circuit 3 in the placement space 53 can be connected to the base 51 or the housing 1, or the control circuit 3 can be located on the connecting shaft 2 located in the placement space 53.

[0054] The aforementioned bracket 52 can be a frame structure, and an installation channel is formed inside the bracket 52. The portion of the connecting shaft 2 located on the side of the base 51 facing away from the housing 1 can enter the installation channel, and the drive shaft of the steering wheel can be inserted into the installation channel formed by the bracket 52 to connect with the connecting shaft 2. Alternatively, the bracket 52 can also be located on the side of the base 51 facing away from the housing 1, and the bracket 52 can be arranged around the connecting shaft 2 so that when the drive shaft of the steering wheel is connected to the connecting shaft 2, the bracket 52 can protect the connecting shaft 2.

[0055] As shown in Figures 1, 2, and 4, in some embodiments, the upper cylinder 5 is provided with a positioning notch 511, and the housing 1 is provided with a positioning protrusion 15, which is inserted into the positioning notch 511. With this arrangement, when the upper cylinder 5 is connected to the housing 1, the positioning protrusion 15 can first be inserted into the positioning notch 511 to determine the relative position of the upper cylinder 5 and the housing 1, improving the convenience of installing the upper cylinder 5 onto the housing 1.

[0056] Specifically, a positioning notch 511 can be provided at the position of the upper column 5 near the housing 1, and a positioning protrusion 15 is provided on the side of the housing 1 facing the upper column 5. When the upper column 5 is installed on the housing 1, the positioning protrusion 15 is first inserted into the positioning notch 511 to determine the position of the upper column 5 on the housing 1, and then the upper column 5 is connected to the housing 1 by welding, bonding or bolting.

[0057] Referring again to Figures 1, 2, and 4, in some embodiments, a bearing 14 is provided between the housing 1 and the connecting shaft 2, and the connecting shaft 2 is sealed to the inner ring of the bearing 14. This arrangement improves the stability of the connecting shaft 2 when rotating on the housing 1, reduces friction during rotation, and the sealed connection between the connecting shaft 2 and the inner ring prevents the magnetorheological fluid from leaking from the housing 1.

[0058] Specifically, the housing 1 has a mounting hole 12, and the bearing 14 is disposed within the mounting hole 12. The bearing 14 includes an inner ring, an outer ring, and multiple rotating components. The diameter of the inner ring is smaller than the diameter of the outer ring, and the inner ring and outer ring are coaxially arranged, with the inner ring located inside the outer ring. Multiple rotating components are disposed between the inner ring and the outer ring; these rotating components can be multiple balls or multiple cylindrical rolling pins. The rotation of these rotating components between the inner ring and the outer ring causes the inner ring to rotate relative to the outer ring.

[0059] The outer ring of the bearing 14 is sealed to the inner wall of the mounting hole 12. The outer ring can be tightly fitted to the inner wall of the mounting hole 12 and bonded with sealant, or the outer ring can be welded to the inner wall of the mounting hole 12 to seal the outer ring to the inner wall of the mounting hole 12, thus preventing the magnetorheological fluid from leaking to the outside of the receiving cavity 11 through the space between the outer ring and the mounting hole 12.

[0060] The connecting shaft 2 described above passes through the inner ring of the bearing 14 and is sealed to the inner ring. In some embodiments, the outer circumferential surface of the connecting shaft 2 can be tightly fitted to the inner ring of the bearing 14, or a sealing material can be filled between the outer circumferential surface of the connecting shaft 2 and the inner ring of the bearing 14, as long as the magnetorheological fluid cannot leak through the space between the connecting shaft 2 and the inner ring.

[0061] As shown in Figures 2 and 4, in some embodiments, the connecting shaft 2 includes a mounting base 22 and a main shaft portion 21. One side of the mounting base 22 is connected to the main shaft portion 21, and the other side is connected to the fan blade 4. The mounting base 22 is placed on the inner ring of the bearing 14 and drives the inner ring to rotate, and the mounting base 22 is sealed to the inner ring of the bearing 14. Specifically, the mounting base 22 can be sealed to the inner ring of the bearing 14 via a sealing ring 23.

[0062] To ensure structural stability and the connection strength between the connecting shaft 2 and the bearing 14, the bearing 14 is typically large. However, the steering wheel experiences relatively low overall force, so a large-diameter connecting shaft 2 is unnecessary for transmitting the force. Nevertheless, to accommodate the bearing 14, the connecting shaft 2 would have a large diameter, wasting material and increasing the overall weight of the vehicle's steering system. Therefore, in this embodiment, the mounting base 22 is used as the structure connecting to the bearing 14, and the main shaft portion 21 extends away from the receiving cavity 11 to connect to the steering wheel. This allows the diameter of the main shaft portion 21 to be smaller than the diameter of the mounting base 22, reducing the material required to manufacture the connecting shaft 2 and thus reducing its weight.

[0063] Specifically, the main shaft portion 21 can be a shaft structure. The main shaft portion 21 is connected to one side of the mounting base 22, and the fan blade 4 is connected to the other side of the mounting base 22. The mounting base 22 can be a disc structure, with a diameter larger than that of the main shaft portion 21. The mounting base 22 can also be a block structure of other shapes. In some embodiments, a portion of the mounting base 22 is inside the inner ring of the bearing 14, and the remaining portion is inside the receiving cavity 11. The mounting base 22 and the inner ring of the bearing 14 can be tightly fitted to achieve a sealed connection between the mounting base 22 and the bearing 14. In other embodiments, a sealing ring 23 can be fitted onto the mounting base 22. The sealing ring 23 abuts against the mounting base 22 and the inner ring of the bearing 14 to achieve a sealed connection between the mounting base 22 and the bearing 14.

[0064] The aforementioned sealing ring 23 is fitted onto the portion of the mounting base 22 located within the receiving cavity 11, and the sealing ring 23 and the inner ring are tightly abutted against each other on the side of the mounting hole 12 closest to the receiving cavity 11 in the axial direction, thereby sealing the sealing ring 23 with the inner ring and sealing the sealing ring 23 with the mounting base 22, preventing the magnetorheological fluid from leaking from the receiving cavity 11 through the space between the mounting base 22 and the inner ring.

[0065] In some other embodiments, the mounting base 22 may be completely disposed inside the inner ring, and the sealing ring 23 may be disposed between the outer peripheral surface of the mounting base 22 and the inner ring. One side of the sealing ring 23 is sealed to the outer peripheral surface of the mounting base 22, and the other side is sealed to the inner ring, thereby sealing the outer peripheral surface of the mounting base 22 to the inner ring.

[0066] In some embodiments, the housing 1 may include a box body 17 and a cover plate 16. The box body 17 has an interior space, and one side of the box body 17 has an opening as a box opening. The cover plate 16 covers the box opening of the box body 17, so that the cover plate 16 and the box body 17 together form a receiving cavity 11. A mounting hole 12 is provided on the cover plate 16. The upper column 5 is mounted on the cover plate 16. When assembling the cover plate 16 and the box body 17, magnetorheological fluid is first poured into the interior of the box body 17, and then the cover plate 16 is mounted on the box body 17. Furthermore, the connecting shaft 2 can be assembled with the mounting hole 12 on the cover plate 16 first, and then the cover plate 16 with the connecting shaft 2 assembled can be mounted on the box body 17, improving the ease of operation of mounting the connecting shaft 2 on the housing 1.

[0067] Referring again to Figures 2 and 4, in some embodiments, the control circuit 3 may include a coil 31 and an electronic control unit 32. The coil 31 is sleeved on the connecting shaft 2, and the electronic control unit 32 is electrically connected to the coil 31 so that the electronic control unit 32 controls the current passing through the coil 31.

[0068] With this configuration, when current flows through the multiple ring structures formed by coil 31, the magnetic fields generated by each ring structure can superimpose, and the magnetic field lines of the overall magnetic field formed by coil 31 extend along the axial direction of connecting shaft 2, increasing the magnetic field strength applied to the magnetorheological fluid by control circuit 3. Electronic control unit 32 controls the current within coil 31 to control the magnetic field strength applied to the magnetorheological fluid. Electronic control unit 32 enhances the automation and intelligence of control circuit 3.

[0069] Specifically, coil 31 can be a structural component formed by spirally bending and coiling a wire, and coil 31 is sleeved on the outer peripheral surface of connecting shaft 2. When current flows in coil 31, the magnetic field lines of the magnetic field generated by coil 31 can extend along the axial direction of connecting shaft 2, increasing the magnetic field strength acting on magnetorheological fluid.

[0070] In some embodiments, the electronic control unit 32 can be a chip, a microcomputer, or an in-vehicle computer, or it can be an in-vehicle ECU (Electronic Control Unit). The two ends of the electronic control unit 32 and the coil 31 are electrically connected via wires. The electronic control unit 32 can be mounted on the connecting shaft 2, so that the electronic control unit 32 rotates with the connecting shaft 2 when the connecting shaft 2 rotates. Furthermore, the wire between the electronic control unit 32 and the coil 31 can be a flexible wire, allowing the wire to wrap around the connecting shaft 2 when the connecting shaft 2 rotates, ensuring that the electronic control unit 32 maintains a continuous electrical connection with the coil 31 while the connecting shaft 2 rotates.

[0071] The aforementioned electronic control unit 32 may be equipped with an angle detector. The angle detector can detect the angle of rotation of the steering wheel relative to its initial position, and the electronic control unit 32 analyzes the angle of steering wheel rotation to adjust the current value within the coil 31. Furthermore, the electronic control unit 32 may also be equipped with various other detectors. For example, the electronic control unit 32 can collect vehicle speed signals, steering wheel angle signals, road feel simulator signals, wheel positions, etc., and comprehensively analyze and calculate the resistance value corresponding to turning the steering wheel, so that the electronic control unit 32 can analyze the angle of steering wheel rotation and adjust the strength of the current within the coil 31.

[0072] The aforementioned electronic control unit 32 can also be electrically connected to the vehicle's onboard computer. The onboard computer can receive the steering wheel's rotation angle data relative to its initial position. After analyzing the steering wheel rotation angle data, the onboard computer sends a command to the electronic control unit 32, which then adjusts the current strength within the coil 31 according to the command. The onboard computer can also collect and analyze vehicle speed signals, steering wheel angle signals, road feel simulator signals, wheel position data, etc., and then send commands to the electronic control unit 32, which in turn adjusts the current strength within the coil 31 according to the commands.

[0073] As shown in Figures 2 and 4, in some embodiments, the fan blade 4 extends radially along the connecting shaft 2. This arrangement increases the contact area between the fan blade 4 and the magnetorheological fluid in the receiving cavity 11, allowing the magnetorheological fluid to exert greater resistance to the rotation of the fan blade 4 when a smaller current flows through the control circuit 3. This reduces the amount of current required to flow through the control circuit 3 and lowers the energy consumption of the steer-by-wire simulator.

[0074] Specifically, the fan blade 4 extends radially along the connecting shaft 2 to increase the area of ​​the fan blade 4 in the rotation direction of the connecting shaft 2, so that the fan blade 4 can come into contact with more magnetorheological fluid when rotating. In addition, the fan blade 4 can also extend axially along the connecting shaft 2, so that the fan blade 4 forms a rectangular panel structure in the receiving cavity 11.

[0075] As shown in Figures 1 to 4, in some embodiments, the limiting structure 13 includes multiple positioning grooves 131. These grooves are radially arranged on the inner wall of the receiving cavity 11, and are spaced apart circumferentially along the receiving cavity 11. This arrangement allows the positioning grooves 131 to limit the cured magnetorheological fluid, enhancing the effect of the limiting structure 13 in restricting the rotation of the cured magnetorheological fluid. When the cured magnetorheological fluid engages with the positioning grooves 131, the force applied to the connecting shaft 2 is dispersed at the connection point between the cured magnetorheological fluid and the positioning grooves 131, preventing stress concentration that could cause the cured magnetorheological fluid to break and allow the connecting shaft 2 to continue rotating.

[0076] Specifically, the positioning groove 131 is a recessed groove formed radially in the connecting shaft 2. When the magnetorheological fluid fills the receiving cavity 11, the magnetorheological fluid will fill multiple positioning grooves 131. When the magnetorheological fluid solidifies, the solid structure formed by the magnetorheological fluid will interlock with the multiple positioning grooves 131. At this time, the force applied to the connecting shaft 2 will be distributed in the multiple positioning grooves 131, avoiding stress concentration that could cause the solidified magnetorheological fluid to break and allow the connecting shaft 2 to continue rotating.

[0077] A second aspect of this application provides a vehicle including a steer-by-wire feel simulator as described in any of the preceding embodiments.

[0078] By using the aforementioned steer-by-wire feel simulator in a vehicle, the structure of the vehicle's steering system can be simplified. By placing the steer-by-wire feel simulator in the vehicle and connecting it to the steering wheel, the driver can experience different steering wheel feeles. Furthermore, when the steering wheel has been turned a set number of times, the steer-by-wire feel simulator can limit further steering wheel rotation, effectively limiting the number of steering wheel turns.

[0079] When the steer-by-wire simulator provided in this application embodiment is used in a vehicle, the end of the main shaft 21 away from the mounting base 22 is connected to the drive shaft of the steering wheel, the housing 1 is fixed inside the vehicle, and when the steering wheel is rotated, the electronic control unit 32 controls the current in the coil 31 according to the angle of rotation of the steering wheel relative to the initial position, thereby changing the resistance of the magnetorheological fluid to the fan blade 4.

[0080] When the steering wheel rotates a set number of turns relative to its initial position, the electronic control unit 32 increases the current in the coil 31 to a value that solidifies the magnetorheological fluid. After solidification, the magnetorheological fluid engages with multiple positioning slots 131, and the solidified magnetorheological fluid encapsulates the fan blades 4, restricting their rotation and thus preventing the steering wheel from rotating further. If the user then turns the steering wheel in the opposite direction, the electronic control unit 32 detects the opposing force acting on the steering wheel and reduces the current in the coil 31, allowing the steering wheel to rotate back to its initial position.

[0081] As shown in Figures 1 to 5, a third aspect of this application provides a steering wheel resistance control method applied to a steer-by-wire feel simulator as described in any of the preceding claims. As shown in Figure 5, the method includes steps S1, S21, S22, and S23.

[0082] In step S1, the resistance to steering wheel rotation is determined based on the rotation angle of the steering wheel relative to its initial position. Specifically, the initial position is the steering wheel position when the vehicle is traveling in a straight line, and the steering wheel can rotate clockwise or counterclockwise in a direction away from the initial position. The current in the control circuit 3 is adjusted according to the angle of rotation of the steering wheel away from the initial position and the direction of force on the steering wheel to adjust the resistance to steering wheel rotation.

[0083] In step S21, when it is necessary to increase the resistance to steering wheel rotation, the current intensity in the control circuit 3 is increased.

[0084] In step S22, when it is necessary to reduce the resistance to steering wheel rotation, the current intensity in the control circuit 3 is reduced.

[0085] In step S23, when the steering wheel needs to be limited from rotating further due to a set angle, the current in the control circuit 3 is increased above the set current to solidify the magnetorheological fluid. Specifically, when the steering wheel rotates to a set number of revolutions and the direction of force on the steering wheel is the same as the direction of rotation, the current in the control circuit 3 is increased above the set current to solidify the magnetorheological fluid and allow it to engage with the positioning groove 131, thereby limiting further rotation of the steering wheel. After the magnetorheological fluid has solidified by rotating the steering wheel to the set angle, the current in the control circuit 3 is reduced when the direction of force on the steering wheel is towards the initial position.

[0086] In some embodiments, the set angle of steering wheel rotation can be determined based on the number of steering wheel rotations designed for the vehicle. For example, if the set number of steering wheel rotations for a sedan is one and a half rotations, i.e., 540° clockwise rotation, and the force applied to the steering wheel is in the clockwise direction, the higher the current intensity in the control circuit 3, the greater the flow resistance of the magnetorheological fluid. When the current in the control circuit 3 increases above the set current, the magnetic field strength generated by the control circuit 3 causes the magnetorheological fluid to solidify, thereby causing the solidified magnetorheological fluid to engage with the limiting structure 13, preventing the fan blade 4 and the solidified magnetorheological fluid from rotating in the receiving cavity 11, thus limiting the steering wheel from continuing to rotate. Alternatively, if the set number of steering wheel rotations for a sedan is one and a half rotations, it can also be 540° counterclockwise rotation, and when the force applied to the steering wheel is in the counterclockwise direction, the current in the control circuit 3 increases above the set current, and the magnetic field strength generated by the control circuit 3 causes the magnetorheological fluid to solidify, limiting the steering wheel from continuing to rotate.

[0087] When the steering wheel is turned to the set number of revolutions, and the direction of the force on the steering wheel is opposite to the direction of rotation, the current in the control circuit 3 is reduced so that the steering wheel can rotate toward the initial position.

[0088] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0089] The above descriptions are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles disclosed herein.

Claims

1. A steer-by-wire simulator, comprising a housing (1), a connecting shaft (2), and a control circuit (3); The housing (1) has an internal cavity (11) filled with magnetorheological fluid and a limiting structure (13) inside the cavity (11). One end of the connecting shaft (2) is connected to the steering wheel, and the other end of the connecting shaft (2) is placed in the receiving cavity (11) and is provided with a fan blade (4). The connecting shaft (2) can rotate to drive the fan blade (4) to stir the magnetorheological fluid. The control circuit (3) is configured to control the resistance of the magnetorheological fluid to the rotation of the fan blade (4), and the magnetorheological fluid, when solidified, cooperates with the limiting structure (13) to restrict the rotation of the fan blade (4) relative to the housing (1).

2. The steer-by-wire feel simulator according to claim 1, wherein, The housing (1) is connected to an internally hollow upper cylinder (5), which is sleeved on the outside of the connecting shaft (2).

3. The steer-by-wire feel simulator according to claim 2, wherein, The upper cylinder (5) includes a base (51) and a bracket (52). The base (51) is connected to the housing (1) so that a placement space (53) is formed between the base (51) and the housing (1). The control circuit (3) is disposed in the placement space (53). The bracket (52) is connected to the base (51) on the side facing away from the housing (1), and the end of the connecting shaft (2) away from the receiving cavity (11) passes through the base (51) and extends into the interior of the bracket (52).

4. The steer-by-wire feel simulator according to claim 2 or 3, wherein, The upper cylinder (5) is provided with a positioning notch (511), and the housing (1) is provided with a positioning protrusion (15). The positioning protrusion (15) is inserted into the positioning notch (511).

5. The steer-by-wire simulator according to any one of claims 1 to 4, wherein, A bearing (14) is provided between the housing (1) and the connecting shaft (2), and the connecting shaft (2) is sealed to the inner ring of the bearing (14).

6. The steer-by-wire feel simulator according to claim 5, wherein, The connecting shaft (2) includes a mounting base (22) and a main shaft (21). One side of the mounting base (22) is connected to the main shaft (21), and the other side of the mounting base (22) is connected to the fan blade (4). The mounting base (22) is placed on the inner ring of the bearing (14) and drives the inner ring to rotate, and the mounting base (22) is sealed to the inner ring of the bearing (14).

7. The steer-by-wire simulator according to any one of claims 1 to 6, wherein, The control circuit (3) includes a coil (31) and an electronic control unit (32). The coil (31) is sleeved on the connecting shaft (2). The electronic control unit (32) is electrically connected to the coil (31) so that the electronic control unit (32) controls the current passing through the coil (31).

8. The steer-by-wire simulator according to any one of claims 1 to 7, wherein, The fan blade (4) extends radially along the connecting shaft (2).

9. The steer-by-wire simulator according to any one of claims 1 to 8, wherein, The limiting structure (13) includes a plurality of positioning grooves (131), which are arranged radially along the connecting shaft (2) on the inner wall of the receiving cavity (11) and are spaced apart circumferentially along the receiving cavity (11).

10. The steer-by-wire simulator according to any one of claims 1 to 9, wherein, The housing (1) includes a box body (17) and a cover plate (16). The box body (17) has an interior space and a box opening on one side. The cover plate (16) covers the box opening so that the cover plate (16) and the box body (17) together form the receiving cavity (11).

11. A vehicle comprising a steer-by-wire feel simulator according to any one of claims 1 to 10.

12. A steering wheel resistance control method, applied to a steer-by-wire feel simulator as described in any one of claims 1 to 10, the method comprising: The resistance to steering wheel rotation (S1) is determined based on the rotation angle of the steering wheel relative to its initial position. When it is necessary to increase the resistance to the rotation of the steering wheel, the current intensity in the control circuit (3) is increased (S21); When it is necessary to reduce the resistance to steering wheel rotation, reduce the current intensity (S22) in the control circuit (3); When the steering wheel needs to be limited from rotating further due to a set angle, the current in the control circuit (3) is increased to a level above the set current to solidify the magnetorheological fluid (S23).

13. The steering wheel resistance control method according to claim 12, wherein, When the steering wheel needs to be limited from rotating further due to a set angle, the current in the control circuit (3) is increased to a level above the set current to solidify the magnetorheological fluid, including: When the steering wheel is rotated to a set number of revolutions, and the direction of the force on the steering wheel is in the same direction as the direction of rotation of the steering wheel, the current in the control circuit (3) is increased to above the set current so that the magnetorheological fluid is solidified.

14. The steering wheel resistance control method according to claim 13, further comprising: When the steering wheel is rotated to the set number of revolutions and the direction of force on the steering wheel is opposite to the direction of rotation of the steering wheel, the current in the control circuit (3) is reduced so that the steering wheel can rotate toward the initial position.

Images