TWI717843B - Rearview mirror control method and vehicle control system - Google Patents

Abstract

A rearview mirror control method and a vehicle control system are provided. The method is adapted to the vehicle control system mounted on a vehicle and includes the following steps. A sight direction of a driver is detected by an eye tracking device. A gaze position projected on a rearview mirror by sight direction is determined. An adjustment angle and an adjustment direction are determined according to relative position between the gaze position and a reference axis. The rearview mirror is adjusted by rotating around the reference axis according to the adjustment angle and the adjustment direction.

Description

Rearview mirror control method and vehicle control system

The invention relates to a driving assistance technology, and more particularly to a rearview mirror control method and a vehicle control system.

For today's various vehicle structures, the rearview mirror system is an indispensable safety device. Generally speaking, the rearview mirror is a flat mirror or convex mirror, which is used to allow the driver to easily see the surrounding environment at the rear and side of the car when reversing and steering, so as to reduce traffic accidents. In order to allow the driver to clearly observe the surrounding conditions of the vehicle, for a variety of different vehicles, their respective rearview mirror systems also have a different number of rearview mirrors, and each of the rearview mirrors will also Set around or inside the vehicle at different angles/positions.

Generally speaking, the driver will adjust the rearview mirror to a suitable angle through the manual or automatic adjustment button, so that he can more clearly grasp the surrounding conditions while driving. However, after a driver adjusts the rearview mirror for his specific posture and position, the adjusted angle of the rearview mirror may no longer be applicable due to certain situations. For example, the driver’s posture changes during the course of driving the vehicle, the driver’s seat has been adjusted, or a special section of road (for example: up and down slopes or curved road sections), the driver may need to adjust the rearview mirror again to get the best Driving vision. As a result, it will cause inconvenience to the driver and danger on the road.

In view of this, the present invention proposes a rear-view mirror control method and a vehicle control system, which can automatically adjust the angle of the rear-view mirror according to the driver's line of sight to improve the convenience and safety of the driver in driving the vehicle.

The embodiment of the present invention provides a rearview mirror control method, which is suitable for a vehicle control system on a vehicle, which includes the following steps: detecting the driver's sight direction by an eye tracking device; determining the sight direction to project on the rearview mirror According to the relative position between the gaze position and the reference axis, the adjustment angle and the adjustment direction are determined; and the rearview mirror is adjusted with the reference axis as the rotation axis according to the adjustment angle and the adjustment direction.

The embodiment of the present invention provides a vehicle control system, which is suitable for a vehicle, and includes an eye tracking device, a storage device, and a processor. The processor is coupled to the eye tracking device and the storage device, and is configured to execute the instructions in the storage device to: detect the driver's gaze direction by the eye tracking device; determine the gaze position projected on the rearview mirror by the gaze direction; according to the gaze position The relative position between the reference axis and the reference axis determines the adjustment angle and the adjustment direction; and the rearview mirror is adjusted based on the adjustment angle and the adjustment direction with the reference axis as the rotation axis.

Based on the above, in the embodiments of the present invention, the driving sight line estimated by the eye tracking technology can be used to automatically adjust the angle of the rearview mirror. Accordingly, for different driving and different driving situations, the rearview mirror of the vehicle will be adaptively adjusted to the angle that allows the driver to obtain the best view.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

Part of the embodiments of the present invention will be described in detail in conjunction with the accompanying drawings. The reference symbols in the following description will be regarded as the same or similar elements when the same symbol appears in different drawings. These embodiments are only a part of the present invention, and do not disclose all the possible implementation modes of the present invention. More precisely, these embodiments are just examples of methods and systems within the scope of the patent application of the present invention.

Fig. 1 is a schematic diagram of a vehicle control system according to an embodiment of the present invention. Please refer to FIG. 1, the vehicle control system 10 includes an eye tracking device 110, a storage device 120, and a processor 130. In an embodiment, the vehicle control system 10 can be configured in various types of vehicles, such as passenger cars, buses, trucks, or trucks. The present invention does not limit the type of vehicle equipped with the vehicle control system 10.

The eye tracking device 110 is a device capable of tracking and measuring eyeball position and eye movement information, and is suitable for detecting the eyeball characteristics of the driver. In one embodiment, the eye tracking device 110 may include a face imaging module for capturing the driver’s face image and eye image, and determining the driver’s sight direction based on the face turning and pupil position . In an embodiment, the eye tracking device 110 may include a light emitting module and an eye imaging module. The light emitting module of the eye tracking device 110 emits light beams toward the eyeball of the driver, and the eye imaging module of the eye tracking device 110 captures eye images. The eye tracking device 110 detects the pupil position and the bright spot position of the driver in the eye image, and determines the current eye direction according to the position correspondence between the pupil position and the bright spot position. The above-mentioned bright spot position is a reflection point formed by illuminating the driver's eyes with the light beam emitted by the light-emitting module.

The storage device 120 is, for example, any type of fixed or removable random access memory (Random Access Memory, RAM), read-only memory (Read-Only Memory, ROM), flash memory (Flash memory), hard disk A disk or other similar devices or a combination of these devices are used to store data, code, images, etc. that may be used in the operation of the driving control system 10. That is, the storage device 120 is further used to record multiple instructions that can be executed by the processor 130.

The processor 130 is coupled to the eye tracking device 110 and the storage device 120 to control the overall operation of the vehicle control system 10. In this embodiment, the processor 130 is, for example, a central processing unit (Central Processing Unit, CPU), or other programmable microprocessor (Microprocessor), digital signal processor (Digital Signal Processor, DSP), programmable Controllers, Application Specific Integrated Circuits (ASIC), Programmable Logic Device (PLD), or other hardware devices with computing capabilities, but this disclosure is not limited to this.

Fig. 2 is a schematic diagram of a vehicle control system and a vehicle according to an embodiment of the present invention. Referring to FIG. 2, if the vehicle control system 10 is applied to the driving environment of the vehicle 22, the eye tracking device 110 can be installed on the rear view mirror M1 of the vehicle to capture the direction of the driver 21 Eye image data to detect the direction of the driver's 21 line of sight. However, FIG. 2 is only an exemplary illustration, and the present invention does not limit the number and actual positions of the eye tracking devices 110, and they can be designed according to actual application conditions. In an embodiment, the eye tracking device 110 may also be installed on the front glass of the driver 2. In one embodiment, when the driver 21 looks into the left side mirror M2, the eye tracking device 110 can detect the driver's line of sight direction E1. Then, the processor 130 may adjust the mirror angle of the left rearview mirror M2 according to the line of sight direction E1 and the gaze position projected on the left rearview mirror M2, for example, rotate the left rearview mirror M2 to the left, right, up or down . Similarly, when the driver 21 looks toward the right side mirror M3, the vehicle control system 10 can adjust the mirror angle of the right side mirror M3 according to the direction of the driver's 21 line of sight. Thereby, the left side mirror M2 and the right side mirror M3 can be dynamically adjusted in response to the line of sight of the driver 21.

Fig. 3 is a flowchart of a rearview mirror control method according to an embodiment of the invention. Please refer to FIG. 3, the method of this embodiment is applicable to the vehicle control system 10 in the above embodiment. The following is a description of the components in the vehicle control system 10 to adjust the rearview mirror according to the driver's line of sight. Detailed steps.

In step S310, the processor 130 uses the eye tracking device 110 to detect the driver's line of sight direction. In one embodiment, the eye tracking device 110 can actively project light beams such as infrared rays onto the driver's iris, and then detect the driver's line of sight direction based on the relative position information between the reflected light spot and the iris in the eye image. In one embodiment, the eye tracking device 110 can detect the direction of the driver's line of sight according to the characteristic changes of the eyeball and the periphery of the eyeball in the eye image. In one embodiment, the eye tracking device 110 can detect the driver's gaze direction according to the change of the iris angle in the eye image. In one embodiment, the direction of the driver's line of sight is angular information with directional properties.

In step S320, the processor 130 determines the gaze position of the line of sight projected on the rear-view mirror (for example, the rear-view mirror M2, M3 shown in FIG. 2). In one embodiment, the processor 130 may determine the gaze position of the line of sight projected on the mirror plane of the rearview mirror according to the position of the rearview mirror and the current mirror angle. Information about the current mirror angle of the rearview mirror can be obtained by a mirror rotation mechanism (such as an electric motor, etc.) that controls the rotation of the rearview mirror. For example, in the case where the mirror center point (or other reference point) of the rearview mirror is the origin of the coordinate system, the processor 130 may obtain the coordinate information of the gaze position on the mirror plane.

Next, in step S330, the processor 130 determines the adjustment angle and the adjustment direction according to the relative position between the gaze position and the reference axis. In one embodiment, the reference axis may be the mirror centerline of the rearview mirror, for example, the rearview mirror is divided into the vertical centerline on the left and right sides (ie, the straight reference axis) and the rearview mirror is divided into the upper and lower sides The horizontal centerline (that is, the horizontal reference axis). The processor 130 may determine the adjustment angle and the adjustment direction according to the relative distance and the relative direction between the gaze position and the reference axis. The adjustment angle is, for example, 5 degrees, 10 degrees or other degrees and so on. However, for safety reasons, the adjustment angle of the rear-view mirror will not be greater than the allowable adjustment angle. The adjustment direction is, for example, rightward, leftward, downward, or upward.

For example, FIG. 4 is a schematic diagram of a situation of a perspective mirror adjustment method according to an embodiment of the invention. Referring to FIG. 4, the processor 130 may detect the driver's gaze direction E1 through the eye tracking device 110, and obtain the driver's gaze position P1 in the rearview mirror M2 accordingly. Then, in one embodiment, the processor 130 can directly calculate the actual distance d1 between the gaze position P1 and the reference axis A1, and obtain the adjustment of the rearview mirror M2 by performing a table lookup or function calculation based on the actual distance d1 The adjustment angle. Then, the processor 130 determines the adjustment direction according to the relative direction between the gaze position P1 and the reference axis A1. Alternatively, in one embodiment, the processor 130 may first determine that the gaze position P1 falls within one of the mirror areas Z1 to Z9 of the rear view mirror M2, and perform a look-up table based on the mirror area Z1 where the gaze position P1 is located. Obtain the corresponding adjustment angle and direction. It should be noted that the division of the rear view mirror M2 into 9 mirror areas Z1 to Z9 in FIG. 4 is taken as an example, but the present invention is not limited thereto. The respective adjustment angles of the mirror areas Z1~Z9 in the lookup table are determined based on the distance between the mirror areas Z1~Z9 and the reference axis A1.

After determining the adjustment angle and adjustment direction for adjusting the rearview mirror, in step S340, the processor 130 adjusts the rearview mirror with the reference axis as the rotation axis according to the adjustment angle and adjustment direction. The processor 130 controls the mirror rotation mechanism (such as an electric motor, etc.) according to the adjustment angle and the adjustment direction to drive the rearview mirror to rotate up, down, left, or right to adjust the mirror angle of the perspective mirror. In this way, whether it is the left-side rearview mirror or the right-side rearview mirror, it can be dynamically adjusted according to the driver's sight direction through the process shown in FIG. 3.

In addition, in an embodiment, the vehicle control system 10 may determine to adjust the rotation speed of the rearview mirror according to the gaze position of the driver looking at the rearview mirror. In one embodiment, the vehicle control system 10 may first determine whether the driver is looking in the rearview mirror, and then decide whether to adjust the rearview mirror, so as to avoid the driver's unexpected misoperation. Examples will be listed below to illustrate.

Fig. 5 is a flowchart of a rearview mirror control method according to an embodiment of the invention. Please refer to FIG. 5, the method of this embodiment is applicable to the vehicle control system 10 in the above embodiment. The following is a description of the components in the vehicle control system 10 to adjust the rearview mirror according to the driver's sight direction. Detailed steps.

In step S501, the processor 130 uses the eye tracking device 110 to detect the driver's line of sight direction. In step S502, the processor 130 determines whether the line of sight direction falls within the angle range determined based on the rearview mirror. When the driver looks into the rear-view mirror, the driver's line of sight direction should fall within a specific angular range, and this angular range is determined by the spatial position of the rear-view mirror. For example, FIGS. 6A and 6B are schematic diagrams of judging whether the line of sight direction falls within the angle range according to an embodiment of the present invention. 6A and 6B, if the horizontal viewing angle component of the line of sight E1 of the driver 21 falls within the angle range ER1 and the vertical viewing angle component of the line of sight direction E1 falls within the angle range ER3, the processor 130 may determine driving The operator 21 is looking to the left side mirror M2. Similarly, assuming that the horizontal viewing angle component of the line of sight direction E2 of the driver 21 falls within the angle range ER2 and the vertical viewing angle component of the line of sight direction E2 falls within the angle range ER3, the processor 130 may determine that the driver 21 is looking to the right Rearview mirror M3. The angle range ER1 to ER3 is set according to the positions of the left side mirror and the right side mirror.

Returning to FIG. 5, if the line of sight direction does not fall within the angle range determined based on the rear view mirror (No in step S502), it means that the driver is not looking at the rear view mirror. Therefore, in step S512, the processor 130 does not adjust the rearview mirror. Conversely, if the line of sight direction falls within the angle range determined based on the rearview mirror (YES in step S502), it means that the driver is looking into the rearview mirror. Therefore, in step S503, the processor 130 determines the gaze position of the line of sight projected on the rearview mirror.

In step S504, the processor 130 determines whether the relative distance between the gaze position and the reference axis is greater than a preset threshold. If the relative distance between the gaze position and the reference axis is not greater than the preset critical value (No in step S504), it means that the gaze position falls in the middle area of the rearview mirror, that is, the current mirror angle of the rearview mirror meets the driver's needs . Therefore, in step S512, the processor 130 does not adjust the rearview mirror.

Conversely, if the relative distance between the gaze position and the reference axis is greater than the preset threshold (No in step S504), it means that the gaze position falls on the edge area of the rearview mirror, that is, the current mirror angle of the rearview mirror does not match Driver needs. Therefore, in step S505, the processor 130 determines the adjustment angle according to the relative distance. It should be noted that the adjustment angle increases as the relative distance increases. In step S506, the processor 130 determines the mirror turning speed according to the relative distance. It should be noted that the turning speed of the mirror surface increases as the relative distance increases. Specifically, the processor 130 may control the rotation motor of the rearview mirror according to the mirror turning speed to drive the rearview mirror to rotate with the reference axis as the rotation axis according to the mirror turning speed. In other words, the farther the fixation position is from the reference axis, the faster the mirror turning speed and the greater the adjustment angle. The way of determining the angle of adjustment and the turning speed of the mirror may include looking up a table or performing calculations based on a preset function relationship.

In step S507, the processor 13 determines that the gaze position is located on the first side or the second side of the reference axis. If the gaze position is on the first side of the reference axis, in step S508, the processor 130 determines that the adjustment direction is the first turning. In step S509, the processor 130 adjusts the rearview mirror according to the first steering, the adjustment angle, and the mirror steering speed. If the gaze position is on the second side of the reference axis, in step S510, the processor 130 determines that the adjustment direction is the second turning. In step S511, the processor 130 adjusts the rearview mirror according to the second steering, the adjustment angle, and the mirror steering speed. In other words, taking the reference axis as the straight reference axis as an example, if the gaze position is on the right side of the straight reference axis, the processor 130 will determine that the adjustment direction is to turn right. If the gaze position is on the left side of the straight reference axis, the processor 130 determines that the adjustment direction is left. Specifically, the processor 130 can control the rotation drive motor of the rearview mirror according to the adjustment direction (ie, the first steering or the second steering), the adjustment angle, and the mirror steering speed to adjust the mirror angle of the rearview mirror so that the rearview mirror It can be automatically adjusted to an angle suitable for the driver's current posture.

In one embodiment, the reference axis includes a straight reference axis and a transverse reference axis. The adjustment angle includes the left and right adjustment angles associated with the vertical reference axis and the up and down adjustment angles associated with the transverse reference axis. The adjustment direction includes the left-right adjustment direction associated with the vertical reference axis and the up-down adjustment direction associated with the transverse reference axis. With two-axis adjustment, the mirror direction of the rearview mirror can be adjusted to the upper left, lower left, upper right or lower right.

7A and 7B are schematic diagrams of a rearview mirror adjustment method according to an embodiment of the invention. Please refer to FIG. 7A and FIG. 7B at the same time. The processor 130 determines that the relative distance d21 between the gaze position P2 and the vertical reference axis A1 is greater than the preset threshold dTH1 and the relative distance d22 between the gaze position P2 and the transverse reference axis A2 is greater than the preset threshold dTH2, so the processor 130 may determine the adjustment angle associated with the vertical reference axis A1 to be'θ2' degrees according to the relative distance d21 and determine the adjustment angle associated with the transverse reference axis A2 to be'θ3' degrees according to the relative distance d22. In addition, since the gaze position P2 falls on the left side S1 of the straight reference axis A1, the processor 130 determines that the left-right adjustment direction R1 is a left turn. Since the gaze position P2 falls on the upper side S3 of the transverse reference axis A1, the processor 130 determines that the up-down adjustment direction R2 is upward rotation. Based on this, the processor 130 can control the rearview mirror M2 to rotate leftward by'θ2' degrees according to the left and right adjustment direction R1, and control the rearview mirror M2 to rotate upward by'θ3' degrees according to the up and down adjustment direction R2.

7A and 7B at the same time, the processor 130 determines that the relative distance d31 between the gaze position P3 and the vertical reference axis A1 is greater than the preset threshold dTH1 but the relative distance d32 between the gaze position P3 and the horizontal reference axis A2 is less than With a preset threshold dTH2, the processor 130 can determine that the adjustment angle associated with the vertical reference axis A1 is'θ1' and the adjustment angle associated with the transverse reference axis A2 is 0 degree. In addition, since the gaze position P2 falls on the left side S1 of the straight reference axis A1, the processor 130 determines that the left-right adjustment direction R1 is a left turn. Based on this, the processor 130 can control the rearview mirror M2 to rotate to the left by θ1 degree according to the left and right adjustment direction R1. It should be noted that comparing the gaze positions P2 and P3, since the relative distance d21 is greater than the relative distance d31, the adjustment angle ‘θ2’ associated with the gaze position P2 is greater than the adjustment angle ‘θ1’ associated with the gaze position P3.

In addition, referring to FIGS. 7A and 7B at the same time, the processor 130 determines that the driver's gaze position P4 is located in the middle zone ZC of the rearview mirror M2, that is, between the gaze position P4 and the vertical reference axis A1 and the horizontal reference axis A2. If the relative distances d41 and d42 are respectively smaller than the preset threshold values dTH1 and dTH2, the processor 130 does not adjust the rearview mirror M2.

In summary, in the embodiment of the present invention, the mirror angle of the rearview mirror can be dynamically changed with the direction of the driver's line of sight. In addition, the adjustment angle, adjustment direction, and mirror turning speed of the rearview mirror can be determined according to the relative distance and relative orientation between the gaze position and the central area on the rearview mirror. In this way, the rearview mirror of the vehicle can be adaptively adjusted automatically for each driver, so that the driver can obtain the best view, and the convenience and safety of the driver in driving the vehicle are improved.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be determined by the scope of the attached patent application.

10: Vehicle control system

110: Eye tracking device

120: storage device

130: processor

22: Vehicle

M1: Rearview mirror inside the car

M2: left side mirror

M3: Right side mirror

E1, E2, E3: sight direction

21: Driver

S310～S340, S501～S512: steps

ER1, ER2, ER3: Angle range

R2: Up and down adjustment direction

R1: Adjust the direction left and right

ZC: Middle area

Z1~Z9: Mirror area

A1, A2: reference axis

P1, P2, P3: Gaze position

Fig. 1 is a schematic diagram of a vehicle control system according to an embodiment of the present invention. Fig. 2 is a schematic diagram of a vehicle control system and a vehicle according to an embodiment of the present invention. Fig. 3 is a flowchart of a rearview mirror control method according to an embodiment of the invention. FIG. 4 is a schematic diagram of a situation of a perspective mirror adjustment method according to an embodiment of the present invention. Fig. 5 is a flowchart of a rearview mirror control method according to an embodiment of the invention. 6A and 6B are schematic diagrams of judging whether the line of sight direction falls within the angle range according to an embodiment of the present invention. 7A and 7B are schematic diagrams of a rearview mirror adjustment method according to an embodiment of the invention.

S310~S340: steps

Claims (12)

A rearview mirror control method is suitable for a vehicle control system on a vehicle. The method includes: detecting a driver's sight direction by an eye tracking device; and determining the sight direction projected on a rearview mirror The gaze position; the adjustment angle and the adjustment direction are determined according to the relative position between the gaze position and a reference axis; and the rearview mirror is adjusted with the reference axis as the rotation axis according to the adjustment angle and the adjustment direction. For example, the rearview mirror control method described in item 1 of the scope of patent application further includes: judging whether the line of sight direction falls within the angle range determined based on the rearview mirror; and if the line of sight direction does not fall within the angle range , Do not adjust the rearview mirror. For the rearview mirror control method described in item 1 of the scope of the patent application, the step of determining the adjustment angle and the adjustment direction according to the relative position between the gaze position and the reference axis includes: if the gaze position and the reference axis If the relative distance between the axes is not greater than a preset threshold, the rearview mirror is not adjusted; and if the relative distance between the gaze position and the reference axis is greater than the preset threshold, the adjustment is determined according to the relative distance Angle, wherein the adjustment angle increases as the relative distance increases. For the rearview mirror control method described in item 3 of the scope of patent application, wherein the step of determining the adjustment angle and the adjustment direction according to the relative position between the gaze position and the reference axis further includes: if the gaze position and the reference axis The relative distance between the reference axes is greater than the preset critical value, and a mirror turning speed is determined according to the relative distance, wherein the mirror turning speed increases with the relative distance, and the reference is based on the adjustment angle and the adjustment direction. The step of adjusting the rearview mirror with the axis as the rotation axis further includes: driving the rearview mirror to rotate with the reference axis as the rotation axis according to the turning speed of the mirror surface. For the rearview mirror control method described in item 1 of the scope of patent application, the step of determining the adjustment angle and the adjustment direction according to the relative position between the gaze position and the reference axis includes: if the gaze position is located at the reference axis On the first side of the axis, the adjustment direction is determined to be the first turning; and if the gaze position is on the second side of the reference axis, the adjustment direction is determined to be the second turning. As for the rearview mirror control method described in item 1 of the scope of patent application, the reference axis includes a straight reference axis and a transverse reference axis, and the adjustment angle includes a left and right adjustment angle associated with the straight reference axis and The vertical adjustment angle of the horizontal reference axis, and the adjustment direction includes the left-right adjustment direction associated with the vertical reference axis and the up-down adjustment direction associated with the horizontal reference axis. A vehicle control system for a vehicle, comprising: an eye tracking device; a storage device storing a plurality of instructions; and a processor, coupled to the eye tracking device and the storage device, configured to execute the instructions To: detect a driver’s gaze direction by the eye tracking device; determine the gaze position of the gaze direction projected on a rearview mirror; determine the adjustment angle and adjustment based on the relative position between the gaze position and a reference axis Direction; and adjust the rearview mirror with the reference axis as the rotation axis according to the adjustment angle and the adjustment direction. For example, in the vehicle control system described in item 7 of the scope of patent application, the processor is further configured to: determine whether the line of sight direction falls within an angle range determined based on the rearview mirror; and if the line of sight direction does not fall Within this angle range, the rearview mirror is not adjusted. For example, the vehicle control system described in item 7 of the scope of patent application, wherein the processor is further configured to: if the relative distance between the gaze position and the reference axis is not greater than a preset threshold, the rear view is not adjusted Mirror; and if the relative distance between the gaze position and the reference axis is greater than the predetermined threshold, the adjustment angle is determined according to the relative distance, wherein the adjustment angle varies with the phase Increase as the distance increases. For example, in the vehicle control system described in claim 9, wherein the processor is further configured to: if the relative distance between the gaze position and the reference axis is greater than the predetermined threshold, determine according to the relative distance A mirror turning speed, wherein the mirror turning speed increases as the relative distance increases; and the rear-view mirror is driven to rotate with the reference axis as the rotation axis according to the mirror turning speed. For the vehicle control system described in claim 7, wherein the processor is further configured to: if the gaze position is located on the first side of the reference axis, determine that the adjustment direction is the first steering; and if the gaze is The position is located on the second side of the reference axis, and the adjustment direction is determined to be the second steering. The vehicle control system described in item 7 of the scope of patent application, wherein the reference axis includes a straight reference axis and a transverse reference axis, and the adjustment angle includes a left and right adjustment angle associated with the straight reference axis and a horizontal adjustment angle associated with the transverse direction. The vertical adjustment angle of the reference axis, and the adjustment direction includes the left-right adjustment direction associated with the straight reference axis and the up-down adjustment direction associated with the transverse reference axis.

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