Autonomous driving steering control method and steering unit

Abstract

To provide a steering control method and a steering unit for automatic driving that drives the steering wheel of a vehicle by a steering wheel motor to turn by a predetermined angle in response to a steering command, and controls the angle of turning of the steering wheel by rotation of the steering wheel motor.SOLUTION: In response to a steering command, the steering wheel of a vehicle is turned by a steering wheel motor by a predetermined angle, and the angle of turning of the steering wheel is controlled by the rotation of the steering wheel motor. When the vehicle is automatically driven along a planned course, the steering command is transmitted to one steering unit if the deviation of the actual trajectory of the vehicle from the planned course is larger than a predetermined value.SELECTED DRAWING: Figure 1B

Description

[Technical field]

[0001] The present invention relates to the field of autonomous driving, and in particular to a steering control method and a steering unit for autonomous driving. [Background technology]

[0002] In current vehicles, the servo motor rotation system (including the servo motor and the driver) has many redundant designs, which leads to high procurement costs, low torque, and low work efficiency. For example, the servo motor rotation system includes components such as a steering column, a torque sensor, a servo motor, and a control module, and the servo motor rotation system starts to work after the vehicle starts. When the vehicle speed falls below a certain speed, the control module issues a control command to the servo motor to output a torque of a corresponding magnitude and direction based on data such as steering torque, rotation direction, and vehicle speed to generate assistance.

[0003] In the current field of autonomous vehicles, such as agricultural machinery, the automatic steering system itself only has a single steering function, and if it is necessary to feed back rotation angle information, the automatic steering system needs an extra external angle sensor, and it is obvious that the installation of the extra sensor increases the cost of the entire steering system. In autonomous vehicles, the cost of the sensor is a relatively important cost. The control system of an autonomous vehicle needs to obtain various parameters through various sensors, and make decisions based on these parameters to automatically control the vehicle and achieve the purpose of autonomous driving. Summary of the Invention [Problem to be solved by the invention]

[0004] One object of the present invention is to provide an automatic driving steering control method and steering unit that eliminates the need for control by a separately installed angle sensor in the rotation system of the handle motor, thereby saving installation costs and subsequent maintenance costs.

[0005] Another object of the present invention is to provide a steering control method and a steering unit for automatic driving, in which the rotation system of the steering wheel motor can adjust the direction based on commands from the vehicle control system so that the vehicle travels along a desired planned route.

[0006] It is yet another object of the present invention to provide a steering control method and a steering unit for automatic driving, which are capable of automatically determining whether the rotation system of the steering wheel motor has returned to the conventional driving mode due to a human hand intervening in the steering wheel.

[0007] Yet another object of the present invention is to provide a steering control method and steering unit for automatic driving, in which a steering motor rotation system drives one steering wheel using one motor, and obtains the rotation angle of the motor to determine the rotation angle of the steering wheel, thereby eliminating the need to detect the rotation angle of the steering wheel using an external angle sensor. [Means for solving the problem]

[0008] According to one aspect of the present invention, a steering control method for autonomous driving includes a step of driving a steering wheel motor to rotate one steering wheel to a predetermined angle in response to a steering command, and the rotation angle of the steering wheel is controlled by the rotation of the steering wheel motor.

[0009] According to one aspect of the present invention, the steering control method includes: When the vehicle is automatically driven along a planned route, if a deviation between an actual trajectory of the vehicle and the planned route is greater than a predetermined value, the method further includes sending the steering command to a steering unit; Here, the steering unit includes the handle motor and the handle.

[0010] According to one aspect of the present invention, the steering control method includes: The method further includes a step of controlling to stop rotation of the steering motor so that the steering wheel is maintained at a current position after the offset value of the actual trajectory of the vehicle with respect to the planned route is corrected to be smaller than a preset value.

[0011] According to one aspect of the present invention, the steering control method further includes the step of: if the vehicle needs to make a U-turn, sending a steering command to a vehicle control unit and controlling the steering unit by the vehicle control unit.

[0012] According to one aspect of the present invention, the steering control method further includes a step of the vehicle control unit sending a command to the steering unit to control a steering motor of the steering unit to operate, and a step of collecting state parameters of the steering motor to determine whether the steering unit is in an idle state, and if so, controlling the steering unit to rotate in response to a command from the vehicle control unit.

[0013] According to one aspect of the present invention, the steering control method includes the steps of: acquiring a rotation speed of the handle motor; The method further includes a step of comparing the rotation speed of the handle motor with a commanded predetermined rotation speed, and controlling the handle motor to accelerate and adjust if the rotation speed of the handle motor is smaller than the commanded predetermined rotation speed.

[0014] According to one aspect of the present invention, in the above method, when the vehicle's course angle is adjusted to a predetermined angle, the vehicle control unit stops rotation of the handle motor of the steering unit, thereby stopping rotation of the handle.

[0015] In one aspect of the invention, the method described above further comprises the step of: once the driver places his or her hands on the steering wheel, the steering motor is deactivated, placing the vehicle under artificial steering control.

[0016] According to another aspect of the present invention, a steering unit according to the present invention is suitable for steering a vehicle, and includes a steering wheel and a steering wheel motor, The handle is drivingly connected to the handle motor, and the handle motor is drivingly connected to a vehicle control unit of the vehicle, and based on an automatic driving command received by the vehicle control unit, the vehicle control unit issues a command to the handle motor so that the rotation angle of the handle is a predetermined angle by driving the handle motor, and here the rotation angle of the handle is controlled by the rotation of the handle motor.

[0017] According to one embodiment of the present invention, the steering unit further includes a handle motor detector that acquires rotation parameters of the handle motor and is communicatively connected to the vehicle control unit, and the command sent by the vehicle control unit includes a setting value of the rotation parameters of the handle motor. [Brief description of the drawings]

[0018] [Figure 1A] 1 is a schematic diagram of a vehicle with a steering unit according to a preferred embodiment of the present invention; [Figure 1B] 1A to 1C are diagrams illustrating an example of application of a steering unit according to a preferred embodiment of the present invention. [Diagram 2] FIG. 1 is a diagram illustrating an example of application of a steering control method according to a preferred embodiment of the present invention. [Diagram 3] FIG. 1 is a diagram illustrating an example of application of a steering control method according to a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The following description is disclosed to enable those skilled in the art to realize the present invention. The preferred embodiments in the following description are merely examples, and modifications obvious to those skilled in the art may be conceived. In the following description, the basic principles of the present invention may be applied to other embodiments, modifications, improvements, equivalents, or other forms that do not depart from the spirit and scope of the present invention.

[0020] In the present disclosure, the orientations and positional relationships indicated by terms such as "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "lateral", "top", "bottom", "inner", "outer", etc. are based on the orientations and positional relationships shown in the drawings, and are merely for the purpose of explaining the present invention and simplifying the explanation of the present invention, and do not indicate or suggest that the devices or elements shown have a particular orientation or are constructed or operated in a particular orientation. Therefore, the above terms are not to be understood as limitations on the present invention.

[0021] The term "one" should be understood as "at least one" or "one or more," i.e., in some embodiments, the number of an element may be one, while in other embodiments, the number of the element may be multiple, and the term "one" is not to be understood as a numerical limitation.

[0022] As shown in FIGS. 1A-1B, a steering unit 15 according to a preferred embodiment of the present invention and a vehicle 1 with a handle 151 are shown, respectively.

[0023] The vehicle 1 may be automatically driven or manually driven. The type of the vehicle 1 may be, but is not limited to, an automobile, a passenger car, a freight car, or an agricultural machine. The steering unit is not limited to the above-mentioned exemplary vehicle 1, but may also be applicable to a movable system with a steering wheel, and steering is realized by steering the steering wheel. The vehicle 1 may be an internal combustion engine vehicle 1, an electric energy vehicle 1, or a vehicle 1 that uses other energy sources.

[0024] The vehicle 1 includes a vehicle body 10 and a vehicle control unit 20 (Electronic Control Unit, ECU). The vehicle body 10 is controllably connected to the vehicle control unit 20. The vehicle body 10 includes a vehicle body frame 11, a traveling unit 12, a drive unit 13, a brake unit 14, and a steering unit 15. The traveling unit 12, the drive unit 13, the brake unit 14, and the steering unit 15 are each mounted on the vehicle body frame 11. The traveling unit 12 is drivably connected to the brake unit 14. The brake unit 14 is used to prevent the traveling unit 12 from moving continuously. The steering unit 15 controls the steering of the traveling unit 12.

[0025] The traveling unit 12, the drive unit 13, the brake unit 14, and the steering unit 15 are each controllably connected to the vehicle control unit 20. The vehicle control unit 20 controls the vehicle body 10 as desired, based on data acquired by various sensors.

[0026] The vehicle 1 further includes an information acquisition unit 30 for acquiring information of the vehicle body 10 itself or information outside the vehicle 1, such as environmental information or external instruction information. The vehicle control unit 20 is communicatively connected to the information acquisition unit 30 for processing data acquired by the information acquisition unit 30, and issues commands based on the processing results to control the vehicle body 10.

[0027] The steering unit 15 includes a handle 151 and a handle motor 152 for driving the handle 151. One output shaft of the handle motor 152 rotates to drive the handle 151 to rotate.

[0028] It is not necessary to provide the steering unit 15 with an additional angle sensor for detecting the rotation angle of the handle 151. The rotation of the handle 151 is realized by the rotation of the output shaft of the handle motor 152. The rotation angle of the handle 151 can be determined by acquiring the rotation angle of the output shaft of the handle motor 152. Furthermore, the steering unit 15 includes a handle motor detector 153 configured to detect the state of the handle motor 152 (for example, parameters such as the rotation speed and steering of the handle motor 152). The handle motor detector 153 is communicably connected to the vehicle control unit 20. This allows the vehicle control unit 20 to know the state of the handle motor 152 in real time, and to issue a command to the handle motor 152 based on the state of the handle motor 152.

[0029] As shown in FIG. 2, an application of the steering unit 15 according to this embodiment to an automatic driving process of the vehicle 1 will be described as an example.

[0030] The vehicle 1 starts automatic driving and travels along a preset route from A to B. After the vehicle 1 travels for a certain period of time, the vehicle control unit 20 knows, based on the data acquired by the information acquisition unit 30, that a certain deviation occurs between the current travel path of the vehicle 1 and the preset route, and the offset value exceeds a preset range. Based on this situation, the vehicle control unit 20 issues a command to the steering unit 15 to start rotating the handle motor 152. As a result, the handle 151 rotates, changing the travel direction of the vehicle body 10.

[0031] In the above process, the information acquisition unit 30 acquires the position information of the vehicle body 10 in real time by GPS or the like. At the same time, the vehicle control unit 20 performs processing based on the data acquired by the information acquisition unit 30. If the current travel path of the vehicle body 10 matches the scheduled route, the vehicle control unit 20 transmits a command to the steering unit 15 to stop the rotation of the handle motor 152 and to hold the handle 151 in the current position. Data on the current rotation angle of the handle motor 152 can be fed back to the vehicle control unit 20 by the information acquisition unit 30 in real time.

[0032] Furthermore, if the vehicle control unit 20 finds, based on the data acquired by the information acquisition unit 30, that the vehicle body 10 has again deviated from the planned route, it may repeat the above-mentioned steps and continue adjusting the steering wheel 151 until the vehicle 1 completes this autonomous driving.

[0033] According to one aspect of the present invention, there is provided a steering control method for autonomous driving, including the following steps.

[0034] After starting automatic driving, the vehicle 1 automatically travels along the set direction. Once the real-time trajectory of the vehicle 1 deviates from the predetermined route and the offset value becomes larger than a preset value, the vehicle control unit 20 sends a command to the steering wheel motor 152 to drive the steering wheel 151 to adjust the traveling direction of the vehicle 1 until the offset value between the real-time trajectory of the vehicle 1 and the predetermined route returns to within a predetermined range.

[0035] In detail, first, when the offset value is larger than a predetermined value, the rotation parameters of the steering wheel motor 152, for example, the rotation speed and the rotation direction, are adjusted, and the data is fed back to the vehicle control unit 20 in real time. Next, when the offset value of the vehicle 1 is adjusted to be within a predetermined range, for example, so that the travel route of the vehicle 1 overlaps with a predetermined route, the vehicle control unit 20 stops the rotation of the steering wheel motor 152, stops the adjustment to the steering wheel 151, and stops the adjustment to the travel direction of the vehicle 1. In other words, at this time, the steering wheel 151 is maintained in the adjusted direction. Finally, when the offset value becomes larger than the preset value again, the vehicle control unit 20 again transmits a command to the steering wheel motor 152 to adjust the position of the steering wheel 151 so that the offset value returns to the normal range or does not deviate.

[0036] For example, when the vehicle 1 is traveling on a straight line and it is detected that the vehicle 1 has deviated to the left after a certain period of time has elapsed, the vehicle control unit 20 controls the rotation of the steering wheel motor 152 to drive the vehicle 1 to the right, return it to the desired straight track, and maintain the adjusted position of the steering wheel 151. If the vehicle 1 deviates to the right after returning to the desired straight track and a certain period of time has elapsed, the vehicle control unit 20 controls the steering wheel motor 152 to rotate in the reverse direction, and controls the steering wheel 151 to rotate in the reverse direction so that the vehicle 1 faces left. In this way, it is preferable to constantly adjust the position of the steering wheel 151 based on the motion trajectory of the vehicle 1.

[0037] After the vehicle 1 returns to the desired straight position, the steering wheel motor 152 may automatically return to the state before the adjustment so that the steering wheel 151 returns to the positive. In other words, after one adjustment is completed, the steering wheel 151 may return to the positive or may be kept in the state after the adjustment.

[0038] Furthermore, if the driver needs to suddenly adjust the direction of travel of the vehicle 1 as required, he can intervene at any time to control the steering wheel 151. To explain by way of example, the vehicle 1 maintains a straight-ahead running direction, and when the driver desires the vehicle 1 to run to the right by turning the steering wheel 151 to the right, the steering unit 15 stops operating. In other words, the steering wheel motor 152 does not maintain the steering wheel 151 in a fixed direction, but turns the steering wheel 151 in response to the driver's operation.

[0039] The steering unit 15 can determine whether or not the driver has intervened in the operation by detecting the force receiving state of the handle motor 152, but it goes without saying that how the steering unit 15 determines whether or not the driver has intervened in the operation is merely an example.

[0040] Furthermore, the vehicle 1 with the steering unit 15 may not only automatically correct its direction when going off course, but may also automatically steer.

[0041] 3, the vehicle 1 can automatically make a U-turn at a required U-turn position. Specifically, the vehicle control unit 20 in the vehicle 1 may receive an external command and transmit a command to the steering unit 15 based on the external command to put the steering unit 15 into an operating state. The vehicle control unit 20 may also obtain parameters from the steering unit 15, such as the current rotation angle of the handle motor 152.

[0042] When the current steering wheel motor 152 is in an idle state, the vehicle control unit 20 generates a control command to drive the steering wheel motor 152 to rotate at a certain rotation speed and steering to rotate the steering wheel 151, based on the parameters of the steering unit 15 and external instructions.

[0043] If the current steering wheel 151 is in operation and, for example, the driver may be steering, the vehicle control unit 20 may provide some kind of indication based on the parameters received from the steering unit 15.

[0044] Furthermore, the information acquisition unit 30 acquires the position state of the vehicle 1 in real time so that the vehicle control unit 20 can determine whether the vehicle body 10 has completed the current operation such as turning a curve. If the vehicle 1 has not completed the current operation and the course angle of the vehicle 1 has not been adjusted to the desired angle, the vehicle control unit 20 continues to send a command to the steering unit 15 to continue turning the handle motor 152 and to continue adjusting the handle 151. If the vehicle control unit 20 determines that the current course angle of the vehicle 1 has reached the desired angle based on the information acquired by the information acquisition unit 30, it sends a command to the steering unit 15 to cause the handle motor 152 of the steering unit 15 to stop turning the handle 151.

[0045] The steering control method may include the following steps: A vehicle control unit 20 receives an automatic driving command from an APP, such as a portable electronic device. A user can operate the vehicle 1 through the portable electronic device.

[0046] The vehicle control unit 20 receives the command and sends an enable command to the steering motor 152 .

[0047] Based on an enable command received from the vehicle control unit 20, the steering motor 152 is activated.

[0048] The state of the steering unit 15 is acquired and fed back to the vehicle control unit 20.

[0049] When the vehicle control unit 20 determines, based on the state of the steering unit 15, that the steering unit 15 is in an idle state, it transmits a steering command to the steering motor 152 to adjust the position of the steering wheel 151.

[0050] The handle motor 152 receives the command and starts rotating.

[0051] If the rotation speed of the handle motor 152 reaches the commanded rotation speed, the handle motor 152 stops rotating, otherwise the handle motor 152 continues to accelerate and adjust.

[0052] The vehicle control unit 20 obtains the course angle information of the vehicle 1, and if the current vehicle 1 is adjusted to the preset course angle, sends a command to the steering unit 15 to stop the operation of the handle motor 152. If not, the vehicle control unit 20 continues to send a command to the steering unit 15 to continue adjusting the steering unit 15.

[0053] Furthermore, in another embodiment, the steering control method includes the following steps.

[0054] In response to a steering command, the handle 151 is driven to rotate to a preset angle. The rotation angle of the handle 151 is controlled by the rotation of a motor for the handle 151.

[0055] When the vehicle 1 is driving automatically along the planned route, if the deviation between the actual trajectory of the vehicle 1 and the planned route is greater than a preset value, the steering command is sent to the steering unit 15 .

[0056] If the actual trajectory of the vehicle 1 is corrected so that the offset value from the planned path is smaller than a preset value, the steering command is sent again to the steering unit 15 to maintain the deviation between the actual trajectory of the vehicle 1 and the planned path as much as possible.

[0057] Specifically, when one vehicle 1 travels along a straight line and discovers after a certain time that the travel trajectory of the vehicle 1 is deviated to the right, the vehicle control unit 20 transmits the steering command to the vehicle 1 to turn the vehicle 1 to the left so that the offset value between the travel trajectory of the vehicle 1 and the planned route becomes smaller than a preset value. After the offset value between the travel trajectory of the vehicle 1 and the planned route becomes smaller than a preset value, the vehicle control unit 20 continues to transmit the steering command to the steering unit 15 of the vehicle 1 to return the steering wheel 151 of the vehicle 1 to a certain angle, thereby reducing the possibility that the offset value between the actual trajectory of the vehicle 1 and the planned route will become large again due to the vehicle 1 continuing to travel to the original angle.

[0058] In this way, the steering of the steering wheel 151 of the vehicle 1 is corrected early, before the offset value between the actual trajectory of the vehicle 1 and the planned path becomes increasingly large. That is, the steering wheel 151 of the vehicle 1 can be corrected in advance.

[0059] In this process, data from the steering unit 15 can be fed back to the vehicle control unit 20 regardless of the time of the artificial intervention in the steering wheel 151. The vehicle control unit 20 can prioritize the artificial intervention operation over the steering command by the vehicle control unit 20.

[0060] After the hand is intervened in the handle 151, the handle motor 152 may stop operating so that the user completely grasps the handle 151. Alternatively, the handle motor 152 may act as an auxiliary. In detail, after the vehicle control unit 20 manually intervenes in the handle 151, the vehicle control unit 20 can know the rotation direction of the handle 151 based on the data acquired from the handle motor 152 by the handle motor detector 153. When the handle 151 is rotated in one direction, the vehicle control unit 20 issues a command to the handle motor 152 so that the handle motor 152 drives the handle 151 according to the rotation direction of the handle 151 based on the data detected by the handle motor detector 153. It becomes more convenient for the user to manually operate the handle 151, and is particularly suitable for operating a large vehicle.

[0061] In addition, the steering unit 15 has an emergency mechanism. In detail, the information acquisition unit 30 of the vehicle 1 during automatic driving constantly acquires environmental information around the vehicle 1. After the user intervenes in the steering wheel 151, the control right of the steering wheel 151 belongs to the user. Based on the information acquired by the information acquisition unit 30, the vehicle control unit 20 discovers that an obstacle has appeared ahead, but if the user does not perform a related operation (e.g., steering) within a preset time and continues to run along the current direction, the vehicle 1 will collide with the obstacle. In this case, the vehicle control unit 20 sends a command to the steering unit 15 so that the steering motor 152 drives and rotates the steering wheel 151. In this process, the user performs steering, but if the direction is opposite to that instructed by the vehicle control unit 20, the priority of the command by the vehicle control unit 20 is higher than the command of the manual operation, and the vehicle 1 is steered to avoid the current obstacle under the control of the vehicle control unit 20.

[0062] It is understood by those skilled in the art that the embodiments of the present invention shown in the above description and drawings are merely illustrative and are not intended to limit the present invention. The objects of the present invention are fully and effectively achieved. Although the function and structural principle of the present invention have been shown and explained in the above embodiments, the embodiments of the present invention can be arbitrarily modified or altered without departing from said principles.

Claims

1. A steering unit having a steering wheel and a steering wheel motor, comprising: a step of driving the steering wheel motor to rotate the steering wheel to a predetermined angle in response to a steering command, and a rotation angle of the steering wheel being controlled by the rotation of the steering wheel motor; a step of transmitting the steering command to the steering wheel motor by an emergency mechanism to drive and rotate the steering wheel so that the vehicle avoids the obstacle when an obstacle appears in a direction in which the vehicle is currently traveling and the driver does not steer the vehicle within a preset time from the detection of the obstacle in a state of manual driving by the driver; During a period in which the vehicle is avoiding the obstacle by the emergency mechanism, if the driver is manually driving the vehicle and the direction in which the driver steers is opposite to the direction based on the steering command, causing the steering wheel motor to execute the steering in priority over the manual driving command by the driver. A steering control method for automatic driving, comprising:

2. 2. The steering control method according to claim 1, further comprising the step of transmitting the steering command to the handle motor when an offset value between an actual trajectory of the vehicle and the planned path is greater than a predetermined value when the vehicle is automatically driven along a planned path.

3. 3. The steering control method according to claim 2, further comprising a step of controlling to stop rotation of the steering motor so that the steering wheel is maintained at a current position after the offset value of the actual trajectory of the vehicle from the planned path is corrected to be smaller than a preset value.

4. 2. The method of claim 1, further comprising the step of: a vehicle control unit transmitting the steering command to the steering motor to adjust the position of the steering wheel if the vehicle needs to make a U-turn.

5. The steering control method described in Claim 4, characterized in that in the step of adjusting the position of the steering wheel, the vehicle control unit continues to send the steering command based on parameters from the steering unit and external instructions until the current vehicle's course angle reaches a desired angle.

6. Obtaining the number of rotations of the handle motor; 6. The steering control method according to claim 5, further comprising a step of comparing the rotation speed of the steering wheel motor with a commanded predetermined rotation speed, and controlling the steering wheel motor to accelerate and adjust if the rotation speed of the steering wheel motor is smaller than the commanded predetermined rotation speed.

7. 7. The steering control method according to claim 6, wherein the vehicle control unit stops rotation of the steering wheel by stopping rotation of the steering wheel motor of the steering unit when the course angle of the vehicle is adjusted to a predetermined angle.

8. A steering control method as described in any one of claims 1 to 7, characterized in that when it is determined that the driver is manually driving the vehicle while the emergency mechanism is not being actuated, the steering wheel motor stops operating and the rotation angle of the steering wheel is controlled by the driver.

9. A steering unit for driving and steering a vehicle, comprising: A handle and a handle motor are provided. the steering wheel is drivably connected to the steering wheel motor, the steering wheel motor is drivably connected to a vehicle control unit of the vehicle, and based on an automatic driving command received by the vehicle control unit, the vehicle control unit issues a steering command to the steering wheel motor so that a rotation angle of the steering wheel becomes a predetermined angle by driving the steering wheel motor; Here, the rotation angle of the handle is controlled by the rotation of the handle motor, The vehicle control unit is characterized in that, when an obstacle appears in the direction in which the vehicle is currently traveling while the vehicle is being manually driven by a driver, if the driver does not steer within a preset time after the vehicle control unit detects the appearance of the obstacle, the vehicle control unit transmits the steering command to the steering motor to drive and turn the steering wheel so that the vehicle avoids the obstacle using an emergency mechanism, and during the period in which the vehicle is avoiding the obstacle using the emergency mechanism, if the driver is manually driving the vehicle and the direction in which the driver steers is opposite to the direction based on the steering command, the steering unit causes the steering motor to execute the steering with priority over the manual driving command from the driver.

10. 10. The steering unit according to claim 9, further comprising a handle motor detector, the handle motor detector acquiring rotation parameters of the handle motor and communicatively connected to the vehicle control unit, and the command sent by the vehicle control unit includes a setting value of the rotation parameter of the handle motor.

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