Steer-by-wire steering feel simulator, vehicle and steering wheel torque calculation method

Abstract

Provided in the present disclosure are a steer-by-wire steering feel simulator, a vehicle, and a steering wheel torque calculation method. The steer-by-wire steering feel simulator comprises a direct drive motor and a steering column system; the direct drive motor comprises a power output shaft; the steering column system comprises a lower steering column, the power output shaft and the lower steering column being coaxially connected to each other. The present disclosure uses a direct drive mode, and no longer provides a deceleration system, so as to solve the problem of system torque fluctuation; the motor has a lower rotation speed, a more stable operation process, and generates slighter noise and vibration in operation, so as to solve the NVH problem. The direct drive motor exhibits good consistency and almost no performance attenuation and degradation after endurance and long-term use, solving the problem of performance consistency after endurance and long-term use. The direct drive motor exhibits good consistency in mass production, and does not require additional running-in, solving the problem of consistency in mass production, improving production efficiency, and allowing for lower requirements for production processes. The steer-by-wire steering feel simulator of the present disclosure has a simplified structure and solves the problem of assembly complexity.

Description

steer-by-wire feel simulator, vehicle and steering wheel torque calculation method

[0001] Cross-references to related applications

[0002] This disclosure is based on and claims priority to Chinese Patent Application No. 202411917575.X, filed on December 23, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of vehicle technology, specifically to a steer-by-wire feel simulator, a vehicle, and a method for calculating steering wheel torque. Background Technology

[0004] The steer-by-wire simulator of the relevant technology uses a reduction system as a reducer connected between the drive motor and the lower column, which has the following problems: large torque fluctuation; in order to ensure mass production consistency, the reduction system needs to be run-in, which reduces production efficiency and places higher demands on the production process; high assembly complexity; it is difficult to guarantee consistency after long-term use and durability; and NVH problems caused by high motor speed. Summary of the Invention

[0005] The purpose of this disclosure is to provide a steer-by-wire feel simulator, a method for calculating torque of a vehicle and a steering wheel, to solve the problems of system torque fluctuation and noise, to solve the problems of mass production consistency, performance consistency after long-term use and durability, to improve production efficiency, to reduce production process requirements, and to solve assembly complexity problems.

[0006] To address the aforementioned technical issues, this disclosure provides a steer-by-wire feel simulator, comprising a direct-drive motor and a column system. The direct-drive motor includes a power output shaft, and the column system includes a lower column. The power output shaft and the lower column are coaxially connected.

[0007] This embodiment of the steer-by-wire simulator uses a direct-drive approach, eliminating the need for a reduction gear system. Firstly, this solves the problem of system torque fluctuation. Secondly, the motor speed is lower, resulting in smoother operation and less noise and vibration, thus addressing the NVH issues present in related steer-by-wire simulators. Thirdly, the direct-drive motor exhibits good consistency, showing almost no performance degradation or aging after prolonged use, requiring no maintenance and maintaining consistent performance throughout its lifecycle, thus resolving the performance consistency issues after prolonged use in related steer-by-wire simulators. Fourthly, the direct-drive motor demonstrates good mass production consistency, eliminating the need for additional running-in, thus resolving mass production consistency issues, improving production efficiency, and lowering the requirements for manufacturing processes. Fifthly, by eliminating the reduction gear system, the structure of the steer-by-wire simulator is simpler, reducing assembly complexity.

[0008] In some embodiments, the power output shaft and the lower tube column are an integral structure, or the power output shaft and the lower tube column are separate structures connected coaxially.

[0009] In some embodiments, the steer-by-wire feel simulator further includes a coupling connecting the power take-off shaft and the lower column.

[0010] In some embodiments, the steer-by-wire simulator further includes a motor controller having an angle sensor for acquiring the rotation angle of the power output shaft.

[0011] In some embodiments, the steer-by-wire simulator further includes a column support, and the direct drive motor is connected to the axial end of the column support.

[0012] In some embodiments, the end of the column support near the direct drive motor is provided with a connecting flange, and the steer-by-wire feel simulator further includes a first connector that connects the connecting flange and the direct drive motor.

[0013] In some embodiments, the direct drive motor includes one or two connection ports, the connection ports including a power port for connecting a power supply cable and a communication port for connecting a communication cable.

[0014] This disclosure also provides a vehicle including the aforementioned steer-by-wire feel simulator.

[0015] The vehicle disclosed herein includes the aforementioned steer-by-wire feel simulator, and therefore has the same technical effects as the aforementioned steer-by-wire feel simulator, which will not be repeated here.

[0016] In some embodiments, the vehicle further includes a vehicle dashboard crossbeam, to which the direct drive motor of the steer-by-wire feel simulator is connected and is rotatable in the vertical direction relative to the vehicle dashboard crossbeam.

[0017] This disclosure also provides a method for calculating steering wheel torque, applicable to the aforementioned steer-by-wire feel simulator. The steer-by-wire feel simulator includes a steering wheel, and the column system further includes an upper column, which connects the steering wheel and the lower column. The method for calculating steering wheel torque includes the following steps:

[0018] The direct drive motor was calibrated to obtain the relationship between the motor current and the torque of the power output shaft;

[0019] Real-time acquisition of current motor current; combined with the relationship between motor current and power output shaft torque, and current motor current to obtain current power output shaft torque.

[0020] The current steering wheel torque is equal to the current power output shaft torque.

[0021] The steering wheel torque calculation method disclosed herein is applicable to the aforementioned steer-by-wire feel simulator, where the power output shaft of the direct drive motor in the steer-by-wire feel simulator is directly connected to the lower column. Therefore, the steering wheel torque is consistent with the power output shaft torque. Thus, the steering wheel torque can be indirectly obtained by obtaining the power output shaft torque. Compared with obtaining the steering wheel torque using a TAS sensor (Torque and Angle Sensor), obtaining the power output shaft torque by detecting the motor current is less costly, making the steer-by-wire feel simulator disclosed herein more economical. Attached Figure Description

[0022] Figure 1 is a schematic diagram of a specific embodiment of the steer-by-wire feel simulator provided in this disclosure;

[0023] Figure 2 is a structural schematic diagram of the second angle of the steer-by-wire feel simulator in Figure 1;

[0024] Figure 3 is a cross-sectional view of the steer-by-wire simulator in Figure 1 along the AA direction;

[0025] Figure 4 is a partial enlarged view of area A of the steer-by-wire feel simulator in Figure 2;

[0026] Reference numerals: 1-Direct drive motor; 11-Power take-off shaft; 12-Connection port; 121-Power port; 122-Communication port; 2-Lower tube column; 3-Motor controller; 4-Tube column bracket; 41-Connecting flange; 5-Upper tube column. Detailed Implementation

[0027] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Please refer to Figures 1-3. Figure 1 is a structural schematic diagram of a specific embodiment of the steer-by-wire feel simulator provided in this disclosure; Figure 2 is a structural schematic diagram of the steer-by-wire feel simulator of Figure 1 from a second angle; Figure 3 is a cross-sectional view of the steer-by-wire feel simulator of Figure 1 along the AA direction.

[0029] This embodiment provides a steer-by-wire feel simulator, including a direct drive motor 1 and a column system. The direct drive motor 1 includes a power output shaft 11, and the column system includes a lower column 2. The power output shaft 11 and the lower column 2 are coaxially connected.

[0030] This embodiment of the steer-by-wire simulator uses a direct-drive method, eliminating the need for a reduction gear mechanism. Firstly, this solves the problem of system torque fluctuation. Secondly, the motor speed is lower, resulting in smoother operation and less noise and vibration, thus addressing the NVH issues present in related steer-by-wire simulators. Thirdly, the direct-drive motor 1 exhibits good consistency, showing almost no performance degradation or aging after durability and long-term use, requiring no maintenance and maintaining consistent performance throughout its entire lifecycle, thus resolving the performance consistency issues after durability in related steer-by-wire simulators. Fourthly, the direct-drive motor 1 demonstrates good mass production consistency, eliminating the need for additional running-in, thus resolving mass production consistency issues, improving production efficiency, and lowering the requirements for manufacturing processes. Fifthly, by eliminating the reduction gear system, the structure of the steer-by-wire simulator is simpler, reducing assembly complexity.

[0031] The power output shaft 11 and the lower tube column 2 are coaxially connected, which can be implemented in the following two ways:

[0032] In the first implementation, the power output shaft 11 and the lower column 2 are separate structures but coaxially connected. In this case, the steer-by-wire simulator also includes a coupling that connects the power output shaft 11 and the lower column 2, enabling the power output shaft 11 and the lower column 2 to rotate synchronously and transmit torque.

[0033] In the second implementation, the power output shaft 11 and the lower column 2 are integrated into one unit. In this case, the power output shaft 11 and the lower column 2 do not need to be connected by a coupling, and structures such as the lower column bearing can be eliminated, reducing the structural complexity of the steer-by-wire simulator in this embodiment and lowering costs.

[0034] Furthermore, in this embodiment, the steer-by-wire feel simulator also includes a motor controller 3, which has an angle sensor for acquiring the rotation angle of the power output shaft 11.

[0035] Since the power output shaft 11 and the lower column 2 are coaxially connected, and the steering wheel is connected to the lower column 2 via the upper column 5, the rotation angle of the power output shaft 11 obtained by the angle sensor is also equivalent to obtaining the rotation angle of the steering wheel. On the one hand, this facilitates the vehicle steering system to accurately control the steering angle of the wheels based on the rotation angle of the steering wheel, ensuring the stability and handling of the vehicle. On the other hand, it eliminates the need for a steering wheel angle sensor, reducing costs and making the steer-by-wire feel simulator of this embodiment more economical and competitive in the market.

[0036] The angle sensor can take the form of an encoder or other structures. The specific structure and working principle of the encoder are existing technologies well known to those skilled in the art, and will not be described in detail here.

[0037] Please continue to refer to Figures 1-3. In this embodiment, the steer-by-wire feel simulator also includes a column support 4, and the direct drive motor 1 is connected to the axial end of the column support 4.

[0038] As configured above, the column bracket 4 in this embodiment can also provide a mounting point for the direct drive motor 1, enabling the integrated installation of the direct drive motor 1. At the same time, the direct drive motor 1 is connected to the axial end of the column bracket 4. The steer-by-wire simulator in this embodiment has a roughly axially symmetrical structure, which reduces the lateral space occupied by the steer-by-wire simulator when it is installed on the vehicle body. This allows the steer-by-wire simulator in this embodiment to be used in both left-hand drive and right-hand drive vehicles, expanding the applicability of the steer-by-wire simulator in this embodiment.

[0039] Please continue to refer to Figure 3. In this embodiment, the end of the column support 4 near the direct drive motor 1 is provided with a connecting flange 41. The steer-by-wire simulator includes a first connector, which connects the direct drive motor 1 and the connecting flange 41.

[0040] The first connecting component can be a threaded connector, such as a connecting bolt. The column support 4 provides a detachable connection method for the direct drive motor 1 by setting a connecting flange 41, which facilitates the installation of the direct drive motor 1 and allows for quick disassembly and replacement of the damaged direct drive motor 1 when it fails, thus facilitating the maintenance of the direct drive motor 1.

[0041] Furthermore, the steer-by-wire simulator in this embodiment also includes a controller, which is electrically connected to the direct drive motor 1. The controller can emit a prompt sound when the power output shaft 11 rotates to a preset angle.

[0042] Specifically, a certain current excitation can be injected into the d-axis or q-axis of the controller's FOC (Field-Oriented Control) algorithm, so that the controller can emit a prompt sound when the power output shaft 11 rotates to a preset angle. The preset angle is usually the angle at which the power output shaft 11 rotates to its limit position. The prompt sound can be a ticking sound, etc., to remind the driver that the steering wheel has been rotated to its limit position, so that the driver can better control the steering wheel rotation angle, thereby better controlling the vehicle's driving state and improving driving safety.

[0043] Please refer to Figure 4, which is a magnified view of area A of the steer-by-wire simulator in Figure 2.

[0044] In this embodiment, the direct drive motor 1 includes one or two connection ports 12, and the connection ports 12 include a power port 121 for connecting a power supply cable and a communication port 122 for connecting a communication cable.

[0045] As configured above, when the direct drive motor 1 includes two connector ports 12, the two connector ports 12 form a redundant design. When one connector port 12 fails, the other connector port 12 can quickly replace the failed connector port 12, enabling the direct drive motor 1 to quickly resume normal operation, improving the reliability and stability of the direct drive motor 1, and enhancing the fault tolerance of the direct drive motor 1. At the same time, due to the existence of the redundant part, technicians can diagnose and repair the faulty part without affecting the normal operation of the direct drive motor 1, thereby improving the maintainability of the direct drive motor 1.

[0046] When the direct drive motor 1 includes a connector port 12, half of the power devices can be eliminated, saving one MCU (Microcontroller Unit) chip, one PMIC (Power Management Integrated Circuit) chip, and one 3-way half-bridge pre-drive chip, thereby reducing the cost of the direct drive motor 1 and the cost of the steer-by-wire feel simulator in this embodiment, making the steer-by-wire feel simulator in this embodiment more economical and competitive in the market.

[0047] This embodiment also provides a vehicle including the aforementioned steer-by-wire feel simulator.

[0048] The vehicle in this embodiment includes the aforementioned steer-by-wire feel simulator, and therefore has the same technical effects as the aforementioned steer-by-wire feel simulator, which will not be repeated here.

[0049] Furthermore, the vehicle in this embodiment also includes a car dashboard crossbeam, and the direct drive motor 1 of the steer-by-wire feel simulator is connected to the car dashboard crossbeam and can rotate relative to the car dashboard crossbeam in the up-down direction.

[0050] As configured above, the direct drive motor 1 can rotate vertically relative to the dashboard crossbeam, allowing the driver to adjust the steering wheel's tilt. Firstly, by adjusting the steering wheel's tilt, taller drivers can adjust it to a suitable angle, avoiding overextension or bending of the arms and maintaining a natural and comfortable arm posture while operating the steering wheel, reducing muscle fatigue. Similarly, shorter drivers can find a suitable angle, ensuring their arms can easily reach the steering wheel without discomfort in their wrists and arms during driving, thus improving driving comfort. Secondly, a suitable steering wheel tilt angle helps obtain better driving visibility; an unsuitable tilt angle may obstruct some information on the instrument panel or affect... By adjusting the steering wheel to a suitable pitch angle, the driver can more clearly see various indicators on the instrument panel (such as vehicle speed, fuel level, and coolant temperature), and also has better forward and side visibility, improving driving safety and convenience. Furthermore, in emergency situations (such as sudden braking or swerving), a suitable steering wheel pitch angle allows the driver to grip the steering wheel better with both hands, enabling more precise control of the vehicle's steering and ensuring the vehicle steers accurately according to the driver's intentions, thus avoiding accidents. Moreover, correct steering wheel pitch adjustment also ensures that the relative position of the driver and airbag is reasonable in the event of an accident, allowing the airbag to provide optimal protection when deployed and reducing the risk of injury to the driver.

[0051] Specifically, in this embodiment, the outer peripheral wall of the direct drive motor 1 is provided with a first connecting ear, the crossbeam of the vehicle dashboard is provided with a corresponding second connecting ear, and a second connecting member is also included. The second connecting member connects the first connecting ear and the second connecting ear. The first connecting ear can rotate around the axial direction of the second connecting member, and the axial direction of the second connecting member is perpendicular to the vertical direction.

[0052] Thus, the second connector first serves to connect the first and second connecting ears. At the same time, the second connector can also act as a rotation axis. When the driver applies an upward or downward force to the steering wheel, the first connecting ear can rotate upward or downward around the axis of the second connector to achieve the pitch angle of the steering wheel.

[0053] The first connecting ear and the second connecting ear are respectively provided with connecting holes. The second connecting member can be in the form of a connecting bolt and a limiting nut. The connecting bolt passes through the connecting holes of the first connecting ear and the second connecting ear in sequence and is connected with the limiting nut to realize the axial limiting connection of the first connecting ear and the second connecting ear.

[0054] This embodiment also provides a method for calculating steering wheel torque, applicable to the aforementioned steer-by-wire feel simulator. The steer-by-wire feel simulator includes a steering wheel, and the column system further includes an upper column 5, which connects the steering wheel and the lower column 2. The method for calculating steering wheel torque includes the following steps:

[0055] The direct drive motor 1 was calibrated to obtain the relationship between the motor current and the torque of the power output shaft;

[0056] Real-time acquisition of current motor current; combined with the relationship between motor current and power output shaft torque, and current motor current to obtain current power output shaft torque.

[0057] The current steering wheel torque is equal to the current power output shaft torque.

[0058] Since the power output shaft 11 of the direct drive motor 1 in this embodiment of the steer-by-wire feel simulator is directly connected to the lower column 2, the steering wheel torque is consistent with the power output shaft torque. Therefore, the steering wheel torque can be indirectly obtained by obtaining the power output shaft torque. Compared with obtaining the steering wheel torque by using a TAS sensor (Torque and Angle Sensor), obtaining the power output shaft torque by detecting the motor current is less expensive, making the steer-by-wire feel simulator in this embodiment more economical.

[0059] In this disclosure, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0060] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0061] In the description of this disclosure, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this disclosure, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this disclosure, as well as the features of different embodiments or examples.

[0062] The above are merely embodiments of this disclosure. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this disclosure, and these improvements and modifications should also be considered within the scope of protection of this disclosure.

Claims

1. A steer-by-wire feel simulator, characterized in that, It includes a direct drive motor (1) and a column system, the direct drive motor (1) including a power output shaft (11), the column system including a lower column (2), and the power output shaft (11) and the lower column (2) being coaxially connected.

2. The steer-by-wire feel simulator according to claim 1, characterized in that, The power output shaft (11) and the lower tube column (2) are an integral structure, or the power output shaft (11) and the lower tube column (2) are separate structures connected coaxially.

3. The steer-by-wire feel simulator according to claim 1 or 2, characterized in that, The steer-by-wire simulator also includes a coupling that connects the power output shaft (11) and the lower column (2).

4. The steer-by-wire simulator according to any one of claims 1 to 3, characterized in that, The steer-by-wire simulator also includes a motor controller (3), which has an angle sensor for obtaining the rotation angle of the power output shaft (11).

5. The steer-by-wire simulator according to any one of claims 1 to 4, characterized in that, The steer-by-wire simulator also includes a column support (4), and the direct drive motor (1) is connected to the axial end of the column support (4).

6. The steer-by-wire feel simulator according to claim 5, characterized in that, The end of the column support (4) near the direct drive motor (1) is provided with a connecting flange (41). The steer-by-wire simulator also includes a first connector, which connects the connecting flange (41) and the direct drive motor (1).

7. The steer-by-wire simulator according to any one of claims 1 to 6, characterized in that, The direct drive motor (1) includes one or two connection ports (12), the connection ports (12) including a power port (121) for connecting a power supply cable and a communication port (122) for connecting a communication cable.

8. A vehicle characterized by comprising: Includes the steer-by-wire feel simulator as described in any one of claims 1 to 7.

9. The vehicle of claim 8, wherein, It also includes a car dashboard crossbeam, wherein the direct drive motor (1) of the steer-by-wire feel simulator is connected to the car dashboard crossbeam and can rotate relative to the car dashboard crossbeam in the up-down direction.

10. A steering wheel torque calculation method, suitable for use in a steer-by- wire feel simulator according to any one of claims 1 to 7, said steer-by-wire feel simulator comprising a steering wheel, a column system further comprising an upper column (5) connecting said steering wheel and said lower column (2), characterized in that, The method for calculating steering wheel torque includes the following steps: The direct drive motor (1) is calibrated to obtain the relationship between the motor current and the torque of the power output shaft; Real-time acquisition of current motor current; combined with the relationship between motor current and power output shaft torque, and current motor current to obtain current power output shaft torque. The current steering wheel torque is equal to the current power output shaft torque.

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