CN114475451A

CN114475451A - Advanced driving assistance system

Info

Publication number: CN114475451A
Application number: CN202011240615.3A
Authority: CN
Inventors: 丁树玺; 邱勇; 粘凤菊; 申琳
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2020-11-09
Filing date: 2020-11-09
Publication date: 2022-05-13

Abstract

The invention relates to an advanced driver assistance system for a vehicle, wherein the advanced driver assistance system comprises a lidar unit, wherein the lidar unit comprises at least one lidar for detecting and identifying the driving environment of the vehicle (1; 211 , 212; 311, 312) and a rotating mechanism for turning the lidar; and an autopilot unit, wherein the autopilot unit controls the lidar unit so that the lidar unit adjusts the detection direction according to the planned path.

Description

Advanced driving assistance system

Technical Field

The invention relates to the technical field of vehicles. The invention relates in particular to an advanced driving assistance system.

Background

In recent years, with rapid development of the vehicle industry, there is an increasing trend toward development of advanced driving assistance systems.

A variety of detection techniques are available in current advanced driving assistance systems to sense the surrounding environment, such as vehicles and other objects in the path of the host vehicle, at any time during the vehicle's travel. Detection techniques include, for example, 360 ° lidar, MEMS lidar, millimeter wave radar, and the like.

A system and method of fusing scanning points from a plurality of laser radars on a vehicle is disclosed, for example, in patent document CN 104035439B. In this solution, the vehicle is provided with a plurality of lidar to provide a 360 ° field of view around the vehicle, wherein the plurality of lidar referred to include side, rear and forward looking lidar and each lidar tracks objects in its respective field of view independently of the other lidar. For another 360-degree laser radar scheme, for example, built-in laser transmitters are vertically arranged and emit outwards at different angles to cover the detection range in the vertical direction, and meanwhile, the laser transmitters are driven by a motor shell rotating at a high speed to realize the full coverage of the detection range in the horizontal direction by 360 degrees, so that the laser transmitters are always in a 360-degree rotating state in the driving process of a vehicle.

However, in a solution using a plurality of lidar to provide a 360 ° field of view of the vehicle, a certain number of lidar, for example four to six lidar, needs to be deployed, which greatly increases the cost of the advanced driving assistance system and the vehicle. In the solution of high-speed continuous rotation of the laser radar, the signal receiving rate is reduced, and high mechanical wear consumption is caused, which affects the detection accuracy.

Disclosure of Invention

The present invention is therefore based on the object of providing an advanced driving assistance system for a vehicle, which can be implemented at low cost while satisfying the requirements for autonomous driving.

This object is achieved by an advanced driver assistance system for a vehicle. The advanced driving assistance system according to the present invention includes a laser radar unit and an automatic driving unit.

In this case, it is particularly preferred that the lidar unit comprises at least one lidar for detecting and detecting the driving environment of the vehicle and a rotary mechanism for rotating the lidar.

In this case, it is particularly preferred that the autopilot unit is able to control the lidar unit such that the lidar unit adjusts the detection direction according to the planned path.

Therefore, when an advanced Driving Assistance system (adas) (advanced Driver Assistance system) works, an automatic Driving unit (adu) (automatic Driving unit) controls the angle of the laser radar relative to the vehicle in real time according to the planned path, and the angle corresponds to the detection area of the corresponding laser radar. The laser radar unit may comprise a smaller number of laser radars. Preferably, the lidar unit comprises one or two lidar. In this case, a smaller number of lidars can be adjusted in angle in real time and flexibly by means of the rotating mechanism, so that the detection range of the lidars covers the region of interest, namely roi (region of interest), determined from the real-time planned path. Thus, the lidar unit is only dedicated to detecting and identifying regions of interest in the vehicle driving environment and feeding back real-time information to the autopilot unit. The automatic driving unit then determines a corresponding driving strategy therefrom. Thus, advanced driving assistance systems, in particular lidar in lidar units, do not need to constantly maintain high rotational speeds, thereby reducing mechanical wear and improving the reliability of the entire sensing unit. In addition, the number of vehicle-mounted laser radars is reduced by the laser radar unit on the premise of ensuring the detection range, and the cost of automatically driving the automobile is greatly reduced.

In a preferred embodiment, the rotation mechanism comprises an electric motor and a transmission assembly for transmitting the rotational movement of the electric motor to the lidar. Advantageously, the transmission assembly constitutes a speed change mechanism, in particular a reduction mechanism. Alternatively, the axis of rotation of the lidar may be parallel to or coincident with the axis of rotation of the output shaft of the motor. Alternatively, the axis of rotation of the lidar may be perpendicular to the axis of rotation of the output shaft of the motor. Therefore, the laser radar can meet different installation requirements and detection range requirements by means of the transmission assembly.

Preferably, the transmission assembly is configured as a gear transmission. Particularly preferably, the transmission assembly is configured as a gear reduction transmission.

Advantageously, the lidar unit comprises a lidar. The laser radar unit can thus be implemented cost-effectively.

Advantageously, the lidar unit comprises two lidar. This makes it possible to increase the detection angle range of the lidar unit to a certain extent, which is advantageous in particular in terms of safety in some driving situations. For example, when the vehicle needs to turn left, the lane to be turned and the road and driving conditions on the left side of the lane where the vehicle is located can be detected simultaneously by arranging two laser radars.

In this case, the lidar unit optionally comprises two lidar units which can be rotated independently of one another by means of a transmission assembly. In this case, the two lidar parts can be rotated about different respective axes of rotation independently of one another under the control of the autopilot unit.

In this case, the lidar unit optionally comprises two lidar units which can be rotated synchronously by means of a transmission assembly. In this case, the two lidar parts can be rotated about a common axis of rotation.

In a preferred embodiment, the autopilot unit adjusts the planned path in real time as a function of the drivability determined by means of the lidar unit.

And if the original planned path is judged to be the drivable path, the laser radar unit continues to adjust the detection direction according to the original planned path.

And if the original planned path cannot be used for driving continuously, judging whether the original planned path can be used for driving continuously after obstacle avoidance driving. In this case, if it is determined that the vehicle can continue to travel on the original planned path after the obstacle avoidance vehicle travels, the laser radar unit continues to adjust the detection direction according to the original planned path; and if the vehicle cannot drive by the original planned path after the obstacle avoidance driving, the automatic driving unit replans the driving path and the laser radar unit adjusts the detection direction according to the updated planned path.

In this case, the autopilot unit can be driven in particular in the region of interest according to the planned route on the basis of the driveability determined by means of the lidar unit.

Preferably, when the vehicle needs to run straight on the lane, the region of interest is a region in front of the vehicle. In this case, the autopilot unit controls the lidar in such a way that the detection angle of the lidar remains forward.

Preferably, when the vehicle needs to change lanes, the region of interest is a region facing the target lane. In the present embodiment, if the laser radar unit obtains a command for lane change from the autonomous driving unit, it is necessary to acquire real-time information of the target lane. For example, when a command of "change to right lane" is obtained, the lidar unit rotates the detection region of the lidar to the right lane and stays in that direction for a certain time to acquire detailed information of the target lane. Then, the information on the driveability of the right lane detected by the lidar is fed back to the autopilot unit. Here, if it is determined from the driveability information that the right lane is unsafe, the automatic driving unit needs to plan a route again or wait until the target lane is safe and then perform lane change. If the right lane is safe according to the driveability information, the vehicle travels to the right lane. During lane change, the lidar will continue to rotate so that the region of interest is in the detection zone of the lidar.

Preferably, when the vehicle needs to turn, the region of interest is a region facing the direction to be turned. In the present embodiment, if the laser radar unit obtains a command regarding turning from the autonomous driving unit, it is necessary to acquire real-time information of the target lane in the direction to be turned. The lidar unit rotates the detection area of the lidar until the detection area corresponds to the area of interest and stays in the direction for a certain time to acquire detailed information of the area until the turning is successful.

Drawings

Preferred embodiments of the present invention are schematically illustrated in the following with reference to the accompanying drawings. The attached drawings are as follows:

fig. 1 is a perspective view of a laser radar unit of an advanced driving assistance system according to a first embodiment;

fig. 2 is a top view of a lidar unit of an advanced driving assistance system according to a first embodiment;

fig. 3 is a perspective view of a lidar unit of an advanced driving assistance system according to a second embodiment;

FIG. 4 is a top view of a lidar unit of an advanced driving assistance system according to a second embodiment;

FIG. 5 is a side view of a lidar unit of an advanced driving assistance system according to a third embodiment;

FIG. 6 is a step diagram of a method of operation of an advanced driving assistance system according to one embodiment;

FIG. 7 is a step diagram of a method of operation of a lidar unit of an advanced driving assistance system according to one embodiment.

Detailed Description

Fig. 1 and 2 schematically show a perspective view and a plan view, respectively, of the structure of a lidar unit of an advanced driving assistance system according to a first embodiment. The advanced driving assistance system according to the present embodiment includes an automatic driving unit in addition to the laser radar unit. In this embodiment the lidar unit comprises a lidar 1, a rotation mechanism and a support 3.

As shown in fig. 1 and 2, the support 3 supports the laser radar 1 and the rotation mechanism and is configured as a support plate in the present embodiment. The rotation mechanism is used to rotate the laser radar 1. The rotation mechanism comprises a motor 4 and a transmission assembly 5 which transmits the rotational movement of the motor to the rotational axis of the lidar 1. The transmission assembly 5 is configured in this embodiment as a reduction transmission gear assembly comprising a pair of intermeshing gears. This allows the rotational motion output by the motor 4 to be transmitted to the rotating shaft of the laser radar 1 at a reduced speed by one step. The laser radar 1 has a detection area 2 for detecting and recognizing the driving environment of the vehicle. The lidar 1 can thus be turned by means of a rotation mechanism under the control of an autopilot unit (not shown) in order to detect the ROI according to the planned path with the detection region 2.

Fig. 3 and 4 schematically show a perspective view and a plan view, respectively, of the structure of a lidar unit of an advanced driving assistance system according to a second embodiment.

As shown in fig. 3 and 4, the lidar unit includes two lidar, i.e., a first lidar 211 and a second lidar 212, a rotating mechanism for rotating the

lidar

211, 212, and a support 230 supporting the

lidar

211, 212 and the rotating mechanism. The support 230 is also designed as a support plate. The rotation mechanism includes a motor 240 and a transmission assembly 250 that transmits rotational motion of the motor 240 to the

lidar

211, 212. Transmission assembly 250 comprises in the present embodiment a gear 253 mounted anti-rotatably at the output shaft of motor 240, a gear 251 mounted anti-rotatably at the rotational axis of first lidar 211, and a gear 252 mounted anti-rotatably at the rotational axis of second lidar 212, wherein gear 253 meshes with gear 251 and gear 252, respectively. The rotational motion output by the motor 240 can thereby be transmitted to the rotational shafts of the

respective lidar

211, 212 via the

gear pair

253, 251 and the

gear pair

253, 252, respectively, with a one-stage deceleration. The

laser radars

211, 212 have

detection regions

221, 222 for detecting and recognizing the driving environment of the vehicle, respectively. The

laser radar

211, 212 can thus be rotated by means of the rotation mechanism under the control of an autopilot unit (not shown) in order to detect the ROI according to the planned path with the detection region 221 and/or the detection region 222.

Fig. 5 schematically shows a side view of the structure of a lidar unit of an advanced driving assistance system according to a third embodiment. The third embodiment is configured similarly to the second embodiment, and in the third embodiment, the lidar unit includes two radars, i.e., a first lidar 311 and a second lidar 312, a rotating mechanism for rotating the

radars

311, 312, and a support 330 that supports the

radars

311, 312 and the rotating mechanism.

However, in the present embodiment, first lidar 311 and second lidar 312 are fixed at a mounting plate 360 that is rotatable relative to support 330. The rotation mechanism includes a motor 340 and a transmission assembly 350 that transmits the rotational motion of the motor 340 to a mounting plate 360. The transmission assembly 350 is configured in this embodiment as a pair of intermeshing gears, one of which is mounted non-rotatably at the output shaft of the motor 340 and the other of which is mounted non-rotatably at the rotational shaft of the mounting plate 360. The rotational motion output by the motor 340 can thereby be transmitted to the rotary shaft of the mounting plate 360 at a reduced speed by one stage. The

laser radars

311, 312 can thus be rotated relative to a common axis of rotation by means of a rotation mechanism under the control of an autopilot unit (not shown). The

laser radars

311, 312 have

detection regions

321, 322 for detecting and recognizing the driving environment of the vehicle, respectively. Whereby the

lidar

311, 312 detects the ROI according to the planned path with the detection region 321 and/or the detection region 322.

FIG. 6 is a step diagram of a method of operation of an advanced driving assistance system according to one embodiment. As shown in fig. 6, when the advanced driving assistance system starts to operate, the vehicle travels on the original planned path. At this time, the lidar unit in the advanced driving assistance system detects the ROI according to the planned path.

The autopilot unit determines whether the originally planned path is a drivable path on the basis of the drivability determined by means of the lidar unit, in particular in the ROI. If the original planned path is judged to be a drivable path, the laser radar unit continues to adjust the detection direction according to the planned path, particularly detect the ROI according to the planned path. If the original planned path cannot be used for driving continuously, further judgment is carried out, namely whether the original planned path can be used for driving continuously after obstacle avoidance driving is carried out.

In this case, if it is determined that the vehicle can continue to travel on the original planned route after the obstacle avoidance travel, the laser radar unit continues to detect the ROI according to the original planned route; if the automatic driving unit judges that the vehicle cannot drive by the original planned path after the obstacle avoidance driving, the automatic driving unit replans the driving path and the laser radar unit detects the ROI according to the updated planned path.

FIG. 7 is a step diagram of a method of operation of a lidar unit of an advanced driving assistance system according to one embodiment. The advanced driving assistance system may be constructed in accordance with the exemplary embodiment described with reference to fig. 1 to 5.

As shown in fig. 7, when the advanced driving assistance system starts operating, the lidar in the lidar unit first detects the area ahead of the vehicle, for example, in an initial state.

When the vehicle needs to keep going straight, change lanes or turn, the automatic driving unit determines the area needing to be detected or the real-time ROI of the laser radar according to the requirement. And the automatic driving unit controls the laser radar in the laser radar unit to rotate correspondingly, so that the ROI is positioned in a detection area of the laser radar. Next, the lidar unit detects real-time information in the ROI and information about drivability is fed back to the autopilot unit. Advanced driving assistance systems, in particular autonomous driving units, make decisions about driving paths from the information about drivability. The driving route decision can be made, for example, according to the exemplary embodiment described with reference to fig. 6.

When the vehicle needs to go straight on the lane, the ROI is the area in front of the vehicle. In this case, the autopilot unit controls the lidar in such a way that the detection region of the lidar is kept facing forward.

When the vehicle needs to change lanes, e.g. when a "change to right lane" command is obtained, the ROI is the area towards the target lane. At this time, the laser radar unit rotates the detection area of the laser radar to the right lane and stays in the direction for a certain time to acquire detailed information of the target lane. Then, information on the driveability of the right lane is fed back to the automatic driving unit. If the right lane is judged to be unsafe, the automatic driving unit needs to plan the path again or wait for the target lane to be safe and then change the lane. If the right lane is safe according to the driveability information, the vehicle travels to the right lane.

When the vehicle needs to turn, the lidar unit obtains a command from the autopilot unit regarding the turn, when the ROI is the area towards the direction to be turned. The lidar unit rotates the detection area of the lidar until the detection area corresponds to the region of interest and stays in the direction for a certain time so as to acquire detailed information of the region until the turning is successful.

Thus, the lidar unit is dedicated only to detecting and identifying regions of interest in the driving environment of the vehicle and feeds back real-time information to the autopilot unit. The automatic driving unit then determines a corresponding driving strategy therefrom. Thus, the lidar in the lidar unit need not be constantly rotating at high speed, thereby reducing mechanical wear and improving the reliability of the entire sensing unit. In addition, the number of vehicle-mounted laser radars is reduced by the laser radar unit on the premise of ensuring the detection range, and the cost of automatically driving the automobile is greatly reduced.

Although possible embodiments have been described by way of example in the above description, it should be understood that numerous embodiment variations exist, still by way of combination of all technical features and embodiments that are known and that are obvious to a person skilled in the art. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. From the foregoing description, one of ordinary skill in the art will more particularly provide a technical guide to convert at least one exemplary embodiment, wherein various changes may be made, particularly in matters of function and structure of the components described, without departing from the scope of the following claims.

List of reference numerals

1 laser radar

2 detection zone

3 support part

4 electric motor

5 Transmission assembly

211 laser radar

212 lidar

221 detection region

222 detection region

230 support

240 motor

250 drive assembly

251 gear

252 Gear

253 Gear

311 laser radar

312 lidar

321 detection region

322 detection zone

330 support

340 electric motor

350 drive assembly

360 mounting plate

Claims

1. An advanced driving assistance system for a vehicle, wherein the advanced driving assistance system comprises:

a lidar unit, wherein the lidar unit comprises at least one lidar (1; 211, 212; 311, 312) for detecting and identifying a vehicle driving environment and a rotation mechanism for rotating the lidar (1; 211, 212; 311, 312); and

and the automatic driving unit controls the laser radar unit to adjust the detection direction according to a planned path.

2. Advanced driving assistance system according to claim 1, wherein the rotation mechanism comprises an electric motor (4; 240; 340) and a transmission assembly (5; 250; 350) transmitting the rotational movement of the electric motor to the lidar (1; 211, 212; 311, 312).

3. Advanced driver assistance system according to claim 2, wherein the transmission assembly (5; 250; 350) is configured as a gear transmission.

4. Advanced driving assistance system according to claim 2 or 3, wherein the lidar unit comprises a bearing block (3; 230; 330) for supporting the lidar (1; 211, 212; 311, 312) and the rotation mechanism.

5. Advanced driving assistance system according to claim 2 or 3, wherein the lidar unit comprises two lidar (211, 212), which two lidar (211, 212) are rotatable independently of each other by means of the transmission assembly (250).

6. Advanced driving assistance system according to claim 2 or 3, wherein the lidar unit comprises two lidar (311, 312), which two lidar (311, 312) are synchronously rotatable by means of the transmission assembly (350).

7. Advanced driving assistance system according to claim 1, wherein the autopilot unit adjusts the planned path in real time depending on the drivability determined by means of the lidar unit.

8. The advanced driving assistance system according to claim 7, wherein if it is determined that the original planned path is a travelable path, the lidar unit continues to adjust the detection direction according to the original planned path.

9. The advanced driving assistance system according to claim 7, wherein if it is determined that the original planned route cannot be continued to be traveled, it is determined whether or not the original planned route can be continued to be traveled after the obstacle avoidance travel.

10. The advanced driving assistance system according to claim 9,

if it is determined that the laser radar unit can continue to travel on the original planned path after the obstacle avoidance, the laser radar unit continues to adjust the detection direction according to the original planned path;

-if it is determined that the vehicle cannot travel the original planned path after obstacle avoidance, the autopilot unit replans the travel path and the lidar unit adjusts the detection direction according to the updated planned path.