Steering device, steering system and vehicle

Abstract

The application discloses a steering device, a steering system and a vehicle. In the steering device, a road feeling simulation unit is arranged in the steering device to actively provide a returning torque to a steering wheel, simulate the returning torque generated by a tire and a ground, a steering wheel positioning parameter, steering inertia and the like in a traditional steering system, and enable a driver to perceive a real steering feeling when using a steer-by-wire system, thereby improving a driving experience and enhancing the perception and control ability of the driver to the vehicle state.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and more particularly to steering devices, steering systems, and vehicles. Background Technology

[0002] Vehicles typically have a steering wheel inside the driver's cabin, allowing the driver to adjust the steering of the wheels and thus control the vehicle's direction. To overcome the technical limitations of traditional steering systems, steer-by-wire systems have been proposed, but their user experience differs from that of a traditional steering wheel and requires further optimization. Summary of the Invention

[0003] This application provides a steering device, a steering system, and a vehicle, which are designed to enable drivers to perceive a near-realistic steering feel when using the steering device, thereby improving the driving experience and enhancing the driver's perception and control of the vehicle's status.

[0004] To achieve the above objectives, according to a first aspect of this application, a steering device is provided for a vehicle, the steering device including a steering wheel, and the steering device further including a road feel simulation unit for providing a return torque to the steering wheel.

[0005] In some alternative implementations, the road feel simulation unit provides a return torque to the steering wheel based on an initial return torque and a feel coefficient.

[0006] In some alternative implementations, the feel coefficient is determined based on driver preference.

[0007] In some alternative implementations, the feel coefficient includes a sports mode feel coefficient and a comfort mode feel coefficient.

[0008] In some alternative implementations, the initial return torque is determined based on at least one of a first return torque, a second return torque, and a third return torque; wherein the first return torque is the return torque generated by the friction between the tire and the ground, the second return torque is the return torque generated by the steering wheel alignment parameters, and the third return torque is the return torque caused by steering inertia.

[0009] In some alternative implementations, the road feel simulation unit is also used to vibrate the steering wheel.

[0010] In some alternative implementations, the steering device is configured to control the road feel simulation unit to vibrate the steering wheel when the vehicle is at risk of instability or when the vehicle moves from a high-friction surface to a low-friction surface.

[0011] In some alternative implementations, the steering wheel includes a folded state and an unfolded state, and the steering wheel is configured to switch from the unfolded state to the folded state by a folding action.

[0012] In some alternative implementations, the feel coefficient of the road feel simulation unit is adjustable and configured as follows:

[0013] When the road feel simulation unit malfunctions, and / or the vehicle's steering system malfunctions, if the steering wheel's angle position is located in a preset center area, the feel coefficient can be adjusted.

[0014] The steering wheel's turning angle is located in a preset central area, including: the steering wheel's turning angle is within ±3°, or the vehicle's lateral acceleration is within 0.1g under the steering wheel's turning angle.

[0015] In some alternative implementations, the road feel simulation unit is configured as follows:

[0016] When the road feel simulation unit malfunctions and / or the vehicle's steering system malfunctions, if the steering wheel's angle position is located in a preset center area, the feel coefficient can be adjusted after the vehicle's steering system switches to the maximum gear ratio mode.

[0017] In some alternative implementations, the self-aligning torque M provided by the road feel simulation unit satisfies:

[0018] M = a1*M1 + b1*M2;

[0019] Wherein, M1 is the road feel torque that needs to be provided to the driver based on the pre-established vehicle dynamics model and the acquired vehicle kinematics information, and M2 is the road surface self-aligning torque value measured and acquired in the vehicle steering system; a1 is the weighting coefficient assigned to M1 according to a predetermined rule, and b1 is the weighting coefficient assigned to M2 according to a predetermined rule.

[0020] In some optional implementations, a1 is a weighting coefficient dynamically assigned to M1 based on vehicle speed and predetermined rules, and b1 is a weighting coefficient dynamically assigned to M2 based on vehicle speed and predetermined rules, and satisfies at least one of the following:

[0021] When the vehicle speed changes from low speed to high speed, a1 decreases or shows a decreasing trend, while b1 increases or shows an increasing trend;

[0022] When the vehicle speed is greater than a predetermined threshold, b1>a1; when the vehicle speed is less than the predetermined threshold, a1>b1.

[0023] In some alternative embodiments, the road feel simulation unit includes a hand-feed motor and a reduction mechanism, the reduction mechanism being drive-connected between the hand-feed motor and the steering wheel; the road feel simulation unit is configured to increase damping by at least one of the following methods based on the current vehicle speed and steering wheel angle when the hand-feed motor in the road feel simulation unit fails:

[0024] Mechanical structure changes;

[0025] The tactile motor is either short-circuited between three phases or between two phases.

[0026] In some alternative implementations, when the vehicle speed is greater than a predetermined threshold, the road feel simulation unit uses a three-phase short circuit of the hand-feed motor to increase damping; when the vehicle speed is less than or equal to the predetermined threshold, the road feel simulation unit uses a two-phase short circuit of the hand-feed motor to increase damping.

[0027] In some alternative implementations, the steering device is configured to switch between a constant gear ratio mode, a small gear ratio mode, and a large gear ratio mode in intelligent driving mode, depending on the driving scenario, vehicle speed, and mode selection.

[0028] In some alternative embodiments, the road feel simulation unit includes a hand-feed motor and a reduction gear, the reduction gear being drively connected between the hand-feed motor and the steering wheel; the steering device is configured to perform at least one of the following upon reaching a soft stop:

[0029] The tactile motor increases the tactile torque;

[0030] Trigger a vibration haptic alert.

[0031] In some optional implementations, the soft stop trigger range is variable depending on the left and right lock angles of the steering wheel, and includes:

[0032] When the left and right lock angles of the steering wheel are ±180 degrees, the soft stop is triggered at the first angle in advance.

[0033] When the left and right lock angles of the steering wheel are ±360 degrees, the soft stop is triggered at the second angle in advance.

[0034] The second angle is greater than the first angle.

[0035] In some alternative embodiments, the output damping of the hand-feed motor is variable and satisfies the following condition: when the left and right lock angles of the steering wheel are ±180 degrees, the output resistance torque of the hand-feed motor is greater than the output resistance torque of the hand-feed motor when the left and right lock angles of the steering wheel are ±360 degrees.

[0036] In some alternative implementations, the steering device is configured to, in intelligent driving mode, disengage the vehicle from manual driving when the driver's intervention on the steering wheel exceeds an inhibition threshold;

[0037] The suppression threshold varies with vehicle speed and steering wheel angle.

[0038] In some alternative implementations, the driver's intervention in the steering wheel exceeds an inhibition threshold, including:

[0039] The driver's input torque to the steering control exceeds the predetermined value.

[0040] In some alternative implementations, the steering mechanism alerts the driver by vibration when at least one of the following occurs:

[0041] The voltage is too high;

[0042] Voltage too low;

[0043] Overheat protection triggered.

[0044] In the aforementioned steering device, by setting a road feel simulation unit in the steering device, a return torque can be actively provided to the steering wheel, simulating the return torque generated by the tires and the ground, steering wheel alignment parameters, steering inertia, etc. in the traditional steering system. This allows the driver to still perceive the real steering feel when using the steer-by-wire system, thereby improving the driving experience and enhancing the driver's perception and control of the vehicle's status.

[0045] A second aspect of this application provides a steering system including the steering device described above.

[0046] A third aspect of this application provides a vehicle that includes the aforementioned steering device or steering system.

[0047] It should be noted that the technical effects of the implementation methods of the second and third aspects can be found in the technical effects of the corresponding implementation methods in the first aspect, and will not be repeated here. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0050] Figure 1 This is a schematic diagram of the vehicle structure provided in an embodiment of this application;

[0051] Figure 2 for Figure 1 A partial structural diagram of the vehicle shown.

[0052] Figure label:

[0053] 2. Dashboard; 8. Steering wheel; 20. Body; 100. Vehicle; 200. Steering system. Detailed Implementation

[0054] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0055] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0056] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0057] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 100 provided in an embodiment of this application. This application provides a vehicle 100. The vehicle 100 can be a pure electric vehicle 100, a hybrid electric vehicle 100, a plug-in hybrid electric vehicle 100, a range-extended electric vehicle 100, a gasoline-powered vehicle, etc. The vehicle 100 can also be a sedan, truck, bus, lorry, trailer, etc. This application does not specifically limit the type of vehicle 100.

[0058] Vehicle 100 may include wheels, body 20, and steering mechanism 200. Wheels are attached to the underside of body 20 and are used to roll on the bottom surface to propel vehicle 100. Steering mechanism 200 is attached to body 20 and connected to wheels, and is used to control wheel steering to facilitate vehicle 100 turning or making U-turns.

[0059] Please see Figure 2 , Figure 2 for Figure 1The diagram shows a partial structural representation of the vehicle 100. The vehicle body 20 may include a cab and an instrument panel 8. The cab is used to house the driver for convenient operation of the vehicle 100. The instrument panel 8 is located at the front of the cab and is used to display parameters of the vehicle 100's operation, such as vehicle speed, engine speed, fuel level, water temperature, battery charge, etc., so that the driver can understand the operating status of the vehicle 100 based on these parameters.

[0060] In some embodiments, the vehicle 100 may further include a driver's seat located in the driver's cab for the driver to sit in, thereby facilitating the driver to drive the vehicle 100.

[0061] In some embodiments, please continue reading Figure 2 The steering device 200 may include a steering wheel 2. The steering wheel 2 is located in the driver's cab and is connected to the wheel drive. The driver can control the vehicle 100 to turn or make a U-turn by turning the steering wheel 2 while sitting in the driver's cab.

[0062] In some embodiments, the steering device 200 may further include a column connected to the dashboard 8 for support. A steering wheel 2 is connected to the column for support. The axis of the column may be a second axis, perpendicular to the width direction of the vehicle 100 and at an angle relative to the length direction of the vehicle 100, thus facilitating the support of the steering wheel 2 in a suitable position for driver use. In some embodiments, the steering device 200 may further include a steering wheel 2 switch assembly, paddle shifters, etc.

[0063] The steering wheel 2, after being connected to the column, is typically located near the dashboard 8. This allows for a more rational arrangement of the dashboard 8 and steering wheel 2 within the driver's cabin, providing the driver with ample space to move around. Of course, in other embodiments, the steering device 200 is not limited to being mounted on the dashboard 8 via the column; it can also be connected to other parts of the vehicle body 20 via other connecting devices.

[0064] In this embodiment, the steering wheel 2 can be a steering wheel with steer-by-wire.

[0065] In some embodiments, the steering wheel 2 may include a folded state and an unfolded state. The steering wheel 2 is configured to switch from the unfolded state to the folded state by a folding action. When the vehicle 100 is in a first driving state, the steering wheel 2 is in the unfolded state. The first driving state is when the vehicle 100 is in motion and the vehicle 100 has not engaged driver assistance.

[0066] When not in use, steering wheel 2 can be folded up, reducing its space-consuming volume and providing the driver with more room to move around, thus improving driver comfort within the vehicle. For example, steering wheel 2 can also be folded up during autonomous driving, or when the vehicle is stationary and used for in-car entertainment functions; it can also be folded up automatically when exiting the vehicle for easier exit and enhanced user experience.

[0067] In some situations where steering wheel 2 is needed, it can be unfolded to facilitate the driver's grip on it while seated in the driver's seat, thus making it easier for the driver to drive vehicle 100. When vehicle 100 is in motion, steering wheel 2 can be unfolded for safety reasons. For example, when the driver gets into the vehicle, steering wheel 2 can be automatically unfolded, which serves both as a welcome gesture and as a way to facilitate the user's driving of vehicle 100 without assisted driving being activated.

[0068] In some embodiments, the folding action can be: the steering wheel 2 rotates around the first direction, where the first direction is the width direction of the vehicle 100. That is, the steering wheel 2 can be switched between a folded state and an unfolded state by rotating the steering wheel 2 around the first direction, which facilitates the switching of the steering wheel 2's state.

[0069] The steering wheel 2 in this application can be automatically folded and unfolded, or it can be folded or unfolded based on manual movement operations, or it can be folded or unfolded based on user commands.

[0070] The folding action can be achieved by an automated mechanism, such as a motor. Alternatively, it can be achieved by manual operation of a mechanical structure by the user.

[0071] In some embodiments, the folding action can also be: the steering wheel 2 retracts relative to the dashboard 8 of the vehicle 100. That is, the steering wheel 2 retracts from both sides towards the middle to reduce the space occupied by the steering wheel 2, thereby providing the driver with more room to move.

[0072] In some embodiments, the folding action may also be a combination of two or three of the above-mentioned folding actions, which will not be elaborated in detail.

[0073] In some other embodiments, the folding action may further include: the steering wheel 2 moving vertically upward; and / or, the steering wheel 2 moving vertically downward. Thus, by moving the steering wheel 2 vertically upward and / or vertically downward, the space required for driver movement can be freed up, providing the driver with more room to move.

[0074] The folding action may include a combination of the above-mentioned folding actions. Several possible folding actions in the embodiments are listed below. The folding action of this application is not limited to the following cases.

[0075] In some possible embodiments, the folding action includes rotating the steering wheel 2 downward about the first axis until it is at least partially below the dashboard 8, or rotating the steering wheel 2 upward about the first axis until it is at least partially above the dashboard 8.

[0076] In some possible embodiments, the folding action includes rotating the steering wheel 2 downward about a first axis and moving the steering wheel 2 downward in a vertical direction so that the steering wheel 2 is at least partially retracted below the dashboard 8.

[0077] In some possible embodiments, the folding action may also include retracting the steering wheel 2 to below the dashboard 8, and then moving the steering wheel 2 upward so that the steering wheel 2 is close to the lower surface of the dashboard, thus saving more interior space.

[0078] In some embodiments, when the steering device is in the unfolded state, the steering wheel 2 is located behind the dashboard 8, and when the steering device is in the folded state, at least a portion of the steering wheel 2 is located below the dashboard 8.

[0079] In the unfolded state, the driver can drive the vehicle normally using the steering wheel 2. At this time, the steering wheel 2 is located behind the dashboard 8, and the driver can easily grip it for steering operations while seated in the driver's cabin. In the folded state, the steering wheel 2 can be folded down when not in use. This reduces the space occupied by the steering wheel 2 in the driver's seat, allowing for more driver freedom of movement and a better riding experience. For example, the steering wheel 2 can be folded, but not limited to, when the vehicle is parked, or when the vehicle is in intelligent driving or autonomous driving mode.

[0080] In the above technical solution, the steering wheel 2 can be folded under the dashboard, reducing the space occupied by the driver's seat and providing more space and comfort for the driver. By placing the steering wheel 2 under the dashboard 8 when not in use, there is no need to redesign the storage space of the dashboard 8. It can be directly applied to the dashboard 8 of existing models, without increasing costs or development cycles, thus ensuring efficiency. Furthermore, the design of the dashboard 8 and steering wheel 2 can be adapted to different vehicle models without special development, allowing for rapid and widespread application across various vehicle types. When the steering wheel 2 is not in use, it can be placed under the dashboard 8.

[0081] Optionally, in an emergency, the driver can grip the steering wheel 2 to perform emergency steering maneuvers, improving safety.

[0082] Optionally, in one embodiment of this disclosure, the steering wheel 2 is configured to rotate about a first direction, which is consistent with the width direction of the vehicle. This facilitates retracting the steering wheel 2 at least partially below the dashboard 8.

[0083] The steering wheel 2 is rotatable and can be at least partially retracted below the dashboard 8 to free up space in the driver's cabin. This increases the space utilization of the driver's cabin when the vehicle is in autonomous driving mode or when the driver is getting in or out of the vehicle, thereby improving the driver's comfort.

[0084] The fact that the first direction aligns with the width of the vehicle demonstrates that the steering wheel 2 can be folded by rotating around this first direction, allowing for easy storage. Meanwhile, the steering wheel 2 itself rotates around the second axis, enabling the vehicle to be steered.

[0085] Alternatively, in another embodiment of this disclosure, the steering wheel 2 is configured to translate in the fore-and-aft direction to at least partially retract the steering wheel 2 below the dashboard 8. It is understood that the steering wheel 2 is not folded, but rather moved directly, and after the movement, it can be at least partially retracted below the dashboard 8, thus freeing up space in the driver's compartment.

[0086] It is understandable that the unfolded state of steering wheel 2 is a state in which the driver can hold steering wheel 2 to perform steering operations, and steering wheel 2 is roughly set up vertically. The folded state of steering wheel 2 allows steering wheel 2 to be rotated and tilted in a certain direction to achieve rotation and folding, so that steering wheel 2 can be set up roughly horizontally.

[0087] In its unfolded state, the steering wheel 2 is in a position where normal driving requires operation, allowing the driver to grip and steer from the driver's seat. In its folded state, the steering wheel 2 generally does not require driver operation. Located below the dashboard 8, it reduces space occupancy in the driver's cabin and avoids excessive encroachment on the driver's legroom, ensuring ample legroom for the driver.

[0088] Alternatively, in one embodiment of this disclosure, in the folded state, the steering wheel 2 is completely retracted below the dashboard 8.

[0089] The phrase "steering wheel 2 completely retracted below the dashboard 8" can mean that, in the folded state, the projection of the steering wheel 2 along the vehicle's height is designated as the first projection area, and the projection of the dashboard 8 along the vehicle's height is designated as the second projection area. The first projection area completely falls within the second projection area, allowing the steering wheel 2 to be completely retracted below the dashboard 8. This arrangement further improves the space utilization of the driver's cabin and enhances comfort. It's understood that when the steering wheel 2 is completely retracted below the dashboard 8, from above, the dashboard 8 completely obscures the steering wheel 2. However, in other examples, "steering wheel 2 completely retracted below the dashboard 8" could mean that the steering wheel 2 is entirely below the dashboard 8 in the height direction and is partially obscured by the dashboard 8.

[0090] Optionally, in one embodiment of this disclosure, the bottom of the dashboard 8 is provided with an upwardly recessed portion, and in the folded state, at least a portion of the steering wheel 2 is located in the recessed portion. The recessed portion accommodates the steering wheel 2, allowing it to be positioned as close as possible to the dashboard 8, thus avoiding excessive occupation of legroom in the driver's compartment and ensuring driver comfort. It is understood that in some examples, after the steering wheel 2 is rotated and folded, the connecting assembly 1 moves the steering wheel 2 to below the dashboard 8. At this time, the connecting assembly 1 can move upwards, causing the steering wheel 2 to move upwards and be accommodated in the recessed portion.

[0091] Alternatively, in another embodiment of this disclosure, the dashboard 8 has a downwardly extending portion on the side facing the driver's seat of the vehicle. In the folded state, the extension portion is used to cover at least part of the steering wheel 2. By providing the extension portion, the steering wheel 2 can be covered after it is folded down below the dashboard 8, thus hiding the steering wheel 2 and improving aesthetics.

[0092] Optionally, in one embodiment of this disclosure, during the transition from an unfolded state to a folded state, the movement of the steering wheel 2 includes a rotational state in which the steering wheel 2 rotates about a first direction, the first direction extending along the width direction of the vehicle. By rotating the steering wheel 2 about the first direction, the steering wheel 2 can be rotated and folded.

[0093] Optionally, in one embodiment of this disclosure, during the process of switching from the unfolded state to the folded state, the movement state of the steering wheel 2 further includes at least one of the following: a downward movement state in which the steering wheel 2 moves downward, a retracted movement state in which the steering wheel 2 moves forward, and an upward movement state in which the steering wheel 2 moves upward.

[0094] The downward movement of the steering wheel 2 allows it to move downwards, which facilitates its rotation around the first direction and avoids interference. It also facilitates its forward movement and avoids interference.

[0095] Among them, the forward-moving retracted state of the steering wheel 2 allows the steering wheel 2 to move forward and be brought as far as possible under the dashboard 8, and the steering wheel 2 can be completely brought under the dashboard 8.

[0096] The upward movement of the steering wheel 2 allows it to rest comfortably under the dashboard 8 after being folded down, reducing legroom requirements. It's understandable that the movement of the steering wheel 2 during the transition from the folded to the unfolded state is the opposite of the movement during the transition from the unfolded to the folded state.

[0097] Optionally, in one embodiment of this disclosure, the steering wheel 2 sequentially passes through a rotating state and a retracted state to switch from an unfolded state to a folded state. It is understood that the steering wheel 2 can switch from an unfolded state to a folded state by rotating around a first direction and moving forward, that is, by retracting the steering wheel 2 under the dashboard 8.

[0098] Optionally, in one embodiment of this disclosure, the steering wheel 2 sequentially passes through a lowered state, a rotated state, a retracted state, and an raised state to switch from an unfolded state to a folded state. It can be understood that the movement of the steering wheel 2 involves it first lowering, then rotating around a first direction, then moving forward, and finally moving upward to rest against the underside of the dashboard 8, thus switching from an unfolded state to a folded state, that is, retracting the steering wheel 2 under the dashboard 8.

[0099] Optionally, in one embodiment of this disclosure, the steering wheel 2 sequentially passes through a rotating state, a lowering state, a retracted state, and an raising state to switch from an unfolded state to a folded state. It can be understood that the movement process of the steering wheel 2 involves first rotating it around a first direction, then lowering it, then moving it forward, and finally moving it upward to rest against the underside of the dashboard 8, thus switching from an unfolded state to a folded state, that is, retracting the steering wheel 2 under the dashboard 8.

[0100] This application discloses a steering device for a vehicle. The steering device 200 includes a steering wheel 8 and a road feel simulation unit for providing a return torque to the steering wheel.

[0101] In traditional steering systems, the self-centering torque felt by the driver through the steering wheel mainly comes from the mechanical transmission system (such as the steering gear, steering tie rods, and the friction between the tires and the ground). However, in steer-on-wire systems, since there is no longer a direct mechanical connection between the steering wheel and the steering actuator, the driver cannot directly perceive the actual road feedback through the mechanical structure, resulting in a lack of steering feel and affecting the driving experience.

[0102] While steer-by-wire systems offer greater structural freedom and flexibility, they lack the natural feedback mechanism of traditional mechanical steering systems, which can easily lead to a lack of directional feel and stability for the driver when turning. By introducing a road feel simulation unit, a self-centering torque can be actively generated, giving the steering wheel an automatic tendency to return to center after turning, thereby enhancing vehicle handling stability, especially at high speeds or in complex road conditions, helping the driver to better control the vehicle's direction.

[0103] The solution of this invention provides a road feel simulation unit in the steering device, which can actively provide a return torque to the steering wheel. This simulates the return torque generated by the tires and the ground, steering wheel alignment parameters, and steering inertia in a traditional steering system. This allows the driver to still perceive a realistic steering feel when using the steer-by-wire system, thereby improving the driving experience and enhancing the driver's perception and control of the vehicle's status.

[0104] The road feel simulation unit can not only simulate the self-centering torque, but also dynamically adjust the magnitude and characteristics of the self-centering torque according to the vehicle's driving conditions (such as vehicle speed, yaw rate, lateral acceleration, etc.) and the driver's operating intentions, thereby achieving intelligent steering control. For example, at high speeds, the self-centering torque can be increased to improve stability; at low speeds or in complex road conditions, the self-centering torque can be appropriately reduced to improve handling agility.

[0105] By obtaining the return torque through the road feel simulation unit, the driver can easily know the operating status of vehicle 100, so as to control vehicle 100 in time when it becomes unstable, and ensure the stability of vehicle 100.

[0106] In some embodiments, the return torque provided by the road feel simulation unit to the steering wheel 2 is determined based on the initial return torque and the feel coefficient. This allows for a more accurate return torque, enabling the driver to accurately control the vehicle 100.

[0107] In some embodiments, the feel coefficient is determined based on driver preference. This allows the feedback return torque to better match the driver's driving habits, improving the driver's driving experience.

[0108] In some embodiments, the feel coefficient includes a sports mode feel coefficient and a comfort mode feel coefficient.

[0109] In some embodiments, the initial return torque is determined based on at least one of a first return torque, a second return torque, and a third return torque; wherein the first return torque is the return torque generated by the friction between the tire and the ground, the second return torque is the return torque generated by the steering wheel alignment parameters, and the third return torque is the return torque caused by steering inertia.

[0110] This allows for more accurate return torque, enabling the driver to control the vehicle more precisely.

[0111] In some embodiments, the road feel simulation unit is also used to vibrate the steering wheel 2. This allows the driver to immediately detect when the vehicle 100 becomes unstable, enabling timely control of the vehicle 100 and minimizing danger.

[0112] In some embodiments, the steering device 200 is configured to control the road feel simulation unit to vibrate the steering wheel 2 when the vehicle 100 is at risk of instability or when the vehicle 100 moves from a high-friction surface to a low-friction surface. These situations can cause the vehicle 100 to become unstable; vibrating the steering wheel 2 through the road feel simulation unit can alert the driver, allowing them to take timely control of the vehicle 100 and avoid danger.

[0113] In some alternative embodiments, the steering wheel 8 includes a folded state and an unfolded state, and the steering wheel 8 is configured to switch from the unfolded state to the folded state by a folding action.

[0114] In some alternative implementations, the feel coefficient of the road feel simulation unit is adjustable and configured as follows:

[0115] When the road feel simulation unit malfunctions, and / or the steering system of the vehicle 100 malfunctions, if the steering wheel 8 is located in a preset center area, the feel coefficient can be adjusted.

[0116] The steering wheel 8 is positioned in a preset central area, including: the steering wheel 8 is within ±3°, or the lateral acceleration of the vehicle 100 is within 0.1g under the steering wheel 8.

[0117] In off-center areas (large-angle steering, such as sharp bends and obstacle avoidance), a sudden change in the feel coefficient (such as torque feedback gain) can cause abrupt changes in the driver's perception, potentially leading to misjudgment of the vehicle's response and causing danger. Returning the steering wheel to the center zone (8 degrees) indicates the vehicle is in a stable state (100 degrees). Switching the feel coefficient at this point will not cause dynamic abrupt changes, ensuring continuous control.

[0118] In some alternative implementations, the road feel simulation unit is configured as follows:

[0119] When the road feel simulation unit malfunctions and / or the steering system of the vehicle 100 malfunctions, if the steering wheel 8 is located in a preset center area, the feel coefficient can be adjusted after the steering system of the vehicle 100 switches to the maximum gear ratio mode.

[0120] A large gear ratio makes steering easy but less responsive; for example, turning the steering wheel a lot only results in a slight turn of the wheels. A small gear ratio makes steering sensitive but requires more effort and can easily lead to oversteering at high speeds.

[0121] When the system detects a malfunction in the steering motor or steering system, it means a decrease in precise feedback and rapid response capabilities. To prevent loss of control, the system actively reduces steering sensitivity, i.e., switches to the maximum gear ratio mode, making the steering "duller." This way, even if the driver makes a mistake, the vehicle 100 will not respond drastically, improving fault tolerance. After the vehicle 100's steering system switches to the maximum gear ratio mode, the steering feel coefficient can be adjusted; switching the steering feel coefficient at this time offers good safety.

[0122] In some alternative implementations, the self-aligning torque M provided by the road feel simulation unit satisfies:

[0123] M = a1*M1 + b1*M2;

[0124] Wherein, M1 is the road feel torque that needs to be provided to the driver based on the pre-established vehicle dynamics model and the acquired vehicle kinematics information, and M2 is the road surface self-aligning torque value measured and acquired in the vehicle's 100 steering system; a1 is the weighting coefficient assigned to M1 according to a predetermined rule, and b1 is the weighting coefficient assigned to M2 according to a predetermined rule.

[0125] In some optional implementations, a1 is a weighting coefficient dynamically assigned to M1 based on vehicle speed and predetermined rules, and b1 is a weighting coefficient dynamically assigned to M2 based on vehicle speed and predetermined rules, and satisfies at least one of the following:

[0126] When the vehicle speed changes from low speed to high speed, a1 decreases or shows a decreasing trend, while b1 increases or shows an increasing trend;

[0127] When the vehicle speed is greater than a predetermined threshold, b1>a1; when the vehicle speed is less than the predetermined threshold, a1>b1.

[0128] In the example:

[0129] M1: The road feel torque that needs to be provided to the driver based on the vehicle dynamics model and vehicle kinematic information (such as vehicle speed, yaw rate, lateral acceleration, etc.), used to simulate the self-centering torque that the driver should feel during steering. M1 is a prediction value based on the vehicle dynamics model, which can reflect the theoretical self-centering requirements of the vehicle in advance during steering.

[0130] M2: The actual road surface self-centering torque value measured in the vehicle's steering system, i.e., the real self-centering torque generated by the friction between the tires and the ground, steering wheel alignment parameters, etc. M2 is an actual measured value that reflects the actual self-centering torque of the vehicle on a real road surface.

[0131] a1: The weighting coefficient assigned to M1, representing the proportion of the road feel torque predicted by the vehicle dynamics model in the final restoring torque;

[0132] b1: The weighting coefficient assigned to M2, representing the proportion of the actual measured road surface straightening moment in the final straightening moment.

[0133] By combining the two with certain weights and integrating model predictions with actual measurements, the self-centering torque that the driver should feel can be simulated more accurately, thus improving the driving experience.

[0134] The dynamic adjustment of weighting coefficients a1 and b1 can adapt to driving needs at different vehicle speeds.

[0135] At low speeds, drivers rely more on vehicle dynamics models to predict the self-centering torque to ensure easy and controllable steering; therefore, a1 > b1. At high speeds, drivers need more feedback from the real road surface to ensure vehicle stability and safety; therefore, b1 > a1. As vehicle speed increases from low to high, a1 tends to decrease while b1 tends to increase to adapt to driving needs at different speeds.

[0136] For example, at low speeds (such as on city roads or in parking lots), drivers prefer light and agile steering. In this case, a1 is larger, and M1 has a more significant effect, making the steering wheel 8 return to center more smoothly and naturally. At high speeds (such as on highways or curves), drivers pay more attention to vehicle stability and the accuracy of the return torque. In this case, b1 is larger, and M2 has a more significant effect, making the steering wheel 8 return to center more forcefully and stably.

[0137] In some alternative embodiments, the road feel simulation unit includes a hand-feed motor and a reduction mechanism, the reduction mechanism being drive-connected between the hand-feed motor and the steering wheel 8; the road feel simulation unit is configured to increase damping by at least one of the following methods based on the current vehicle speed and the steering wheel 8 angle when the hand-feed motor in the road feel simulation unit fails:

[0138] Mechanical structure changes;

[0139] The tactile motor is either short-circuited between three phases or between two phases.

[0140] In some alternative implementations, when the vehicle speed is greater than a predetermined threshold, the road feel simulation unit uses a three-phase short circuit of the hand-feed motor to increase damping; when the vehicle speed is less than or equal to the predetermined threshold, the road feel simulation unit uses a two-phase short circuit of the hand-feed motor to increase damping.

[0141] When the steering motor fails, the system can replace or supplement the damping force provided by the motor by modifying the mechanical structure, such as adding a friction damping device, changing the transmission path, or introducing a mechanical limiting structure. This allows the system to still provide some steering resistance even when the motor fails. For example, introducing a friction disc or elastic element into the reduction mechanism provides additional damping force through mechanical friction or elastic deformation when the motor fails; changing the transmission ratio or introducing a mechanical locking structure restricts the rotation of the steering wheel 8 within a specific angle range, thereby providing steering resistance.

[0142] When the hand-feel motor fails, the motor windings can be short-circuited between phases to utilize the motor's electrical characteristics and simulate a damping effect, thereby increasing steering damping.

[0143] A phase-to-phase short circuit is achieved by forcibly forming a closed, low-resistance circuit between two or three phase windings, inducing a current in the windings. The change in current generates a braking torque, which, in the event of motor failure, increases steering damping through the electromagnetic damping force generated by the short circuit.

[0144] When the vehicle speed exceeds a predetermined threshold (such as high-speed driving), a three-phase phase-to-phase short circuit is used to generate greater damping force, thereby enhancing steering stability at high speeds. When the vehicle speed is less than or equal to the predetermined threshold (such as low-speed driving or parking), a two-phase phase-to-phase short circuit is used to provide moderate damping force, thereby maintaining steering ease at low speeds while still providing some road feel feedback.

[0145] In some alternative embodiments, the steering device 200 is configured to switch between a constant gear ratio mode, a small gear ratio mode, and a large gear ratio mode in intelligent driving mode, depending on the driving scenario, vehicle speed, and mode selection. The gear ratio can be the steering system angle gear ratio: the ratio of the increment of the steering system angle to the increment of the steering wheel angle on the same side; if it is expected that the lower steering wheel needs to turn by the same angle, the larger this value is, the larger the angle that the steering wheel 8 needs to turn.

[0146] For example, the transmission ratio can be set in different modes as follows.

[0147] (1) Constant transmission ratio mode

[0148] Applicable scenarios: regular driving, urban roads, medium-speed driving, etc.

[0149] Features: The transmission ratio remains constant, ensuring that the driver experiences a consistent steering feel at different vehicle speeds.

[0150] Advantages: Simple to operate, easy to adapt to, and suitable for most driving scenarios.

[0151] Disadvantages: It cannot optimize steering characteristics based on vehicle speed or driving scenario.

[0152] (2) Small transmission ratio mode

[0153] Applicable scenarios: low-speed driving, parking, operation in confined spaces, autonomous driving takeover, etc.

[0154] Features: With a small transmission ratio and a small steering wheel rotation angle, a large steering wheel angle can be achieved.

[0155] advantage:

[0156] Improved steering sensitivity facilitates precise maneuvering at low speeds or in confined spaces;

[0157] It reduces the driver's workload, especially when switching from automatic driving mode to manual driving, and helps to take over quickly.

[0158] Disadvantages: At high speeds, the steering may feel "light" and affect stability.

[0159] (3) High transmission ratio mode

[0160] Applicable scenarios: high-speed driving, curves, complex road conditions, etc.

[0161] Features: The transmission ratio is relatively large, and the steering wheel 8 can rotate at a relatively large angle in order to achieve a smaller steering wheel angle.

[0162] advantage:

[0163] Enhanced steering stability, providing a "heavier" steering feel at high speeds to prevent oversteering or understeering;

[0164] Improve driving safety and handling, especially on curves or in complex road conditions.

[0165] Disadvantages: The steering feel is relatively heavy, which may affect the agility of low-speed handling.

[0166] The steering system 200 achieves dynamic switching of the transmission ratio through an intelligent control module (such as a vehicle controller or steering controller), which may include:

[0167] Automatically switches based on driving scenarios (such as curves, straight roads, and narrow spaces);

[0168] Based on vehicle speed (e.g., switching to low gear ratio mode when below a certain threshold, and switching to high gear ratio mode when above a certain threshold);

[0169] Switch between modes based on the selected mode (such as automatic driving mode, manual driving mode, sport mode, comfort mode, etc.).

[0170] In some alternative embodiments, the road feel simulation unit includes a hand-feed motor and a reduction mechanism, the reduction mechanism being drively connected between the hand-feed motor and the steering wheel 8; the steering device 200 is configured to perform at least one of the following after reaching a soft stop:

[0171] The feel motor increases the perceived torque. It simulates road feedback torque, providing steering resistance, self-centering torque, and other features to enhance the driver's perception of road conditions. In the soft-stop region, the feel motor increases the output perceived torque to provide more noticeable steering resistance, allowing the driver to perceive the approaching steering limits. This increase in torque can be linear or non-linear, depending on system settings and driver needs.

[0172] Trigger haptic feedback. In the soft stop area, the system can also trigger haptic feedback, conveying a warning to the driver that the steering limits are approaching through vibration feedback from the steering wheel 8.

[0173] In some optional embodiments, the soft stop trigger range is variable with the left and right lock angles of the steering wheel 8, and includes:

[0174] When the left and right lock angles of the steering wheel 8 are ±180 degrees, the soft stop is triggered at the first angle in advance.

[0175] When the steering wheel lock angle is ±360 degrees, the soft stop is triggered at the second angle in advance.

[0176] The second angle is greater than the first angle.

[0177] A soft stop refers to the point at which the system begins to gradually increase steering resistance as the steering wheel 8 approaches its mechanical limits (i.e., the locked position) to prevent further rotation of the steering wheel 8, thus avoiding oversteering or the abrupt feeling of mechanical locking. The trigger range of this soft stop (i.e., how many degrees before the lock position resistance begins to be applied) can be dynamically adjusted according to the locking angle range of the steering wheel 8.

[0178] When the left and right lock angles of the steering wheel 8 are ±180° (i.e., the steering wheel 8 can rotate within a range of 360°), the soft stop is triggered at the first angle (e.g., 15°) in advance.

[0179] When the left and right lock angles of steering wheel 8 are ±360° (i.e., the range of rotation of steering wheel 8 is 720°), the soft stop is triggered at the second angle (e.g., 30°) in advance.

[0180] The second angle is greater than the first angle (e.g., 30° > 15°) to ensure that the driver can still perceive the approaching steering limit in a timely manner during a wider range of steering operations.

[0181] When the steering wheel lock angle range is small (e.g., ±180°), the driver's steering operation range is limited, and the steering limit is closer to the normal driving scenario. Therefore, triggering the soft stop earlier (e.g., 15°) can provide steering resistance feedback earlier and prevent misoperation or oversteering.

[0182] When the steering wheel has a large 8-lock angle range (e.g., ±360°), the driver has a wider range of steering operations and a greater steering limit. Therefore, triggering the soft stop earlier (e.g., 30°) can provide steering resistance feedback at an earlier stage, preventing the driver from making mistakes due to a lack of perception when turning over a wide range.

[0183] In some alternative embodiments, the output damping of the hand-feed motor is variable and satisfies the following condition: when the left and right locking angles of the steering wheel 8 are ±180 degrees, the output resistance torque of the hand-feed motor is greater than the output resistance torque of the hand-feed motor when the left and right locking angles of the steering wheel 8 are ±360 degrees.

[0184] With a lock angle of ±180°, the steering range of steering wheel 8 is relatively small. In actual driving, the driver is more likely to approach the steering limit. Therefore, a larger resistance torque is needed to warn the driver of the steering limit in advance, prevent misoperation or oversteering, and improve steering stability and safety.

[0185] With a ±360° lock angle, the steering wheel 8 has a large steering range. In certain special scenarios (such as autonomous driving or large-range steering operations), the driver may need more flexible steering control. Therefore, the resistance torque is appropriately reduced to avoid excessive steering resistance affecting the flexibility of operation.

[0186] Steering wheel left and right lock angle: The total amount of rotation of the steering wheel from one extreme position to the other extreme position.

[0187] In some alternative embodiments, the steering device 200 is configured such that, in intelligent driving mode, when the driver's intervention on the steering wheel 8 exceeds an inhibition threshold, the vehicle 100 disengages to manual driving.

[0188] The suppression threshold varies with vehicle speed and steering wheel angle.

[0189] In some alternative implementations, the driver's intervention in the steering wheel 8 exceeds a suppression threshold, including:

[0190] The driver's input torque to the steering control exceeds the predetermined value.

[0191] The suppression threshold refers to the critical value at which the system determines whether the driver needs to take over the vehicle in intelligent driving mode, and is used to determine whether the driver has effectively intervened with the steering wheel.

[0192] At high speeds, the system has a lower tolerance for driver intervention and a smaller suppression threshold, meaning the driver only needs to apply a small amount of torque to trigger mode switching. At low speeds, the system has a higher tolerance for driver intervention and a larger suppression threshold, meaning the driver needs to apply a larger amount of torque to trigger mode switching.

[0193] The torque applied by the driver to the steering control device is one of the key indicators for determining whether the driver is intervening with the steering wheel. When the torque applied by the driver to the steering wheel 8 exceeds a predetermined value (i.e., the suppression threshold), the system determines that the driver has effectively intervened in the vehicle and triggers the vehicle 100 to switch from intelligent driving mode to manual driving mode. This predetermined value can be dynamically adjusted based on information such as vehicle speed, steering wheel 8 angle, and driver grip state to improve the accuracy and safety of the judgment.

[0194] In some alternative implementations, the steering device 200 alerts the driver by vibration when at least one of the following occurs:

[0195] The voltage is too high;

[0196] Voltage too low;

[0197] Overheat protection triggered.

[0198] Vibration alerts allow drivers to detect system anomalies in a timely manner, preventing steering failure or system malfunctions caused by abnormal voltage or overheating.

[0199] In the aforementioned steering device 200, by setting a road feel simulation unit in the steering device 200, a return torque can be actively provided to the steering wheel 8, simulating the return torque generated by the tires and the ground, steering wheel positioning parameters, steering inertia, etc. in the traditional steering system, so that the driver can still perceive the real steering feel when using the steer-by-wire system, thereby improving the driving experience and enhancing the driver's perception and control of the vehicle 100 status.

[0200] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0201] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0202] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0203] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A steering device for a vehicle, characterized in that, The steering device includes: steering wheel; A road feel simulation unit is used to provide a return torque to the steering wheel.

2. The steering device according to claim 1, characterized in that, The road feel simulation unit provides a return torque to the steering wheel based on the initial return torque and the feel coefficient.

3. The steering device according to claim 2, characterized in that, The feel coefficient satisfies at least one of the following: The feel coefficient is determined based on driver preference; The feel coefficient includes the feel coefficient for sports mode and the feel coefficient for comfort mode.

4. The steering device according to claim 2, characterized in that, The initial return torque is determined based on at least one of the first return torque, the second return torque, and the third return torque; wherein the first return torque is the return torque generated by the friction between the tire and the ground, the second return torque is the return torque generated by the steering wheel alignment parameters, and the third return torque is the return torque caused by steering inertia.

5. The steering device according to claim 1, characterized in that, The road feel simulation unit is also used to make the steering wheel vibrate.

6. The steering device according to claim 5, characterized in that, The steering device is configured to control the road feel simulation unit to vibrate the steering wheel when the vehicle is at risk of instability or when the vehicle moves from a high-friction surface to a low-friction surface.

7. The steering device according to any one of claims 1-6, characterized in that, The steering wheel includes a folded state and an unfolded state, and the steering wheel is configured to switch from the unfolded state to the folded state by a folding action.

8. The steering device according to claim 2, characterized in that, The feel coefficient of the road feel simulation unit is adjustable and configured as follows: When the road feel simulation unit malfunctions, and / or the vehicle's steering system malfunctions, if the steering wheel's angle position is located in a preset center area, the feel coefficient can be adjusted. The steering wheel's turning angle is located in a preset central area, including: the steering wheel's turning angle is within ±3°, or the vehicle's lateral acceleration is within 0.1g under the steering wheel's turning angle.

9. The steering device according to claim 8, characterized in that, The road feel simulation unit is configured as follows: When the road feel simulation unit malfunctions and / or the vehicle's steering system malfunctions, if the steering wheel's angle position is located in a preset center area, the feel coefficient can be adjusted after the vehicle's steering system switches to the maximum gear ratio mode.

10. The steering device according to claim 1, characterized in that, The restoring torque M provided by the road feel simulation unit satisfies: M = a1*M1 + b1*M2; Wherein, M1 is the road feel torque that needs to be provided to the driver based on the pre-established vehicle dynamics model and the acquired vehicle kinematics information, and M2 is the road surface self-aligning torque value measured and acquired in the vehicle steering system; a1 is the weighting coefficient assigned to M1 according to a predetermined rule, and b1 is the weighting coefficient assigned to M2 according to a predetermined rule.

11. The steering device according to claim 10, characterized in that, a1 is a weighting coefficient dynamically assigned to M1 based on vehicle speed and predetermined rules, and b1 is a weighting coefficient dynamically assigned to M2 based on vehicle speed and predetermined rules, and both satisfy at least one of the following: When the vehicle speed changes from low speed to high speed, a1 decreases or shows a decreasing trend, while b1 increases or shows an increasing trend; When the vehicle speed is greater than a predetermined threshold, b1>a1; when the vehicle speed is less than the predetermined threshold, a1>b1.

12. The steering device according to claim 1, characterized in that, The road feel simulation unit includes a hand-feed motor and a reduction mechanism, the reduction mechanism being drive-connected between the hand-feed motor and the steering wheel; the road feel simulation unit is configured to, when the hand-feed motor in the road feel simulation unit fails, increase damping based on the current vehicle speed and steering wheel angle value by at least one of the following methods: Mechanical structure changes; The tactile motor is either short-circuited between three phases or between two phases.

13. The steering device according to claim 12, characterized in that, When the vehicle speed is greater than a predetermined threshold, the road feel simulation unit uses a three-phase short circuit of the hand-feed motor to increase damping; when the vehicle speed is less than or equal to the predetermined threshold, the road feel simulation unit uses a two-phase short circuit of the hand-feed motor to increase damping.

14. The steering device according to claim 1, characterized in that, The steering device is configured to switch between a constant transmission ratio mode, a small transmission ratio mode, and a large transmission ratio mode in intelligent driving mode, depending on the driving scenario, vehicle speed, and mode selection.

15. The steering device according to claim 1, characterized in that, The road feel simulation unit includes a hand-feed motor and a reduction mechanism, the reduction mechanism being drive-connected between the hand-feed motor and the steering wheel; the steering device is configured to perform at least one of the following after reaching the soft stop: The tactile motor increases the tactile torque; Trigger a vibration haptic alert.

16. The steering device according to claim 15, characterized in that, The soft stop trigger range is variable depending on the left and right lock angles of the steering wheel, and includes: When the left and right lock angles of the steering wheel are ±180 degrees, the soft stop is triggered at the first angle in advance. When the left and right lock angles of the steering wheel are ±360 degrees, the soft stop is triggered at the second angle in advance. The second angle is greater than the first angle.

17. The steering device according to claim 15, characterized in that, The hand-feed motor has variable output damping and satisfies the following condition: when the left and right lock angles of the steering wheel are ±180 degrees, the output resistance torque of the hand-feed motor is greater than the output resistance torque of the hand-feed motor when the left and right lock angles of the steering wheel are ±360 degrees.

18. The steering device according to claim 1, characterized in that, The steering device is configured to switch the vehicle to manual driving when the driver's intervention on the steering wheel exceeds an inhibition threshold in intelligent driving mode. The suppression threshold varies with vehicle speed and steering wheel angle.

19. The steering device according to claim 18, characterized in that, The driver's intervention in the steering wheel exceeding the inhibition threshold includes: The driver's input torque to the steering control exceeds the predetermined value.

20. The steering device according to claim 1, characterized in that, The steering system alerts the driver by vibration when at least one of the following conditions occurs: The voltage is too high; Voltage too low; Overheat protection triggered.

21. A steering system, characterized in that, The steering device includes any one of claims 1-20.

22. A vehicle, characterized in that, It includes the steering device according to any one of claims 1-20, or the steering system according to claim 21.

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