WO2020164222A1

WO2020164222A1 - Scanning device and laser radar

Info

Publication number: WO2020164222A1
Application number: PCT/CN2019/094821
Authority: WO
Inventors: 任建峰; 虞爱华
Original assignee: 昂纳信息技术（深圳）有限公司
Priority date: 2019-02-14
Filing date: 2019-07-05
Publication date: 2020-08-20
Also published as: CN109828257A

Abstract

Disclosed is a scanning device, belonging to the field of laser radars, and comprising a rotating support (110) capable of rotating around a rotating shaft; a reflector (120) fixedly arranged on the rotating support; a magnetic member (130) fixedly arranged on the rotating support; and a magnetic field generating mechanism (200) that generates a variable-direction magnetic field (201), wherein the magnetic member (130) is arranged in the variable-direction magnetic field (201) and moves in a reciprocating motion under the action of the variable-direction magnetic field to drive the rotating support (110) to rotate in a reciprocating motion. A laser radar is further disclosed. The scanning device has the advantages of a small size, a high rotating speed, and a high efficiency in comparison with a rotary scanning system driven by an electric motor, has the advantages of a lower cost, a smaller size, a higher power consumption and a better environmental adaptation in comparison with a traditional galvanometric scanning system, and has the advantages of a larger scanning area, a wider range of scanning angle, and being more practical in comparison with an MEMS.

Description

Scanning device and laser radar

Technical field

The invention relates to the field of laser radar, in particular to a scanning device and laser radar.

Background technique

Lidar is a radar system that emits laser beams to detect the position and speed of the target. Its working principle is to transmit a detection signal (laser beam) to the target, and then compare the received signal (target echo) from the target with the transmitted signal. After proper processing, the relevant information of the target can be obtained, such as Target distance, azimuth, height, speed, attitude, and even shape and other parameters.

Especially in the field of autonomous driving, technologies such as autonomous driving are developing rapidly. One of the important supporting sensors, lidar, has emerged in various types of solutions in order to meet various specific needs.

Currently, the solutions used for lidar scanning mainly include motor-driven rotating scanning systems, galvanometer scanning systems and emerging MEMS scanning systems. Among them, the MEMS micromirror refers to an optical MEMS device manufactured by optical MEMS technology, which integrates a micro-optical mirror and a MEMS driver. The movement mode of MEMS micromirror includes two kinds of mechanical movement, translation and torsion.

The motor-driven rotating scanning system is suitable for 360° wide field of view scanning. When used for partial field of view scanning, its scanning efficiency is obviously insufficient, and it is difficult to meet the requirements of high-efficiency scanning. The galvanometer scanning system is suitable for scanning in a small field of view, but it has the problems of large volume, high power consumption, and narrow operating temperature range. The MEMS galvanometer scanning system is small in size and light in weight. The current problem with the scanning mirror is that the area of the scanning mirror is relatively small, and the scanning field of view is also relatively small, resulting in that it cannot meet the needs of the industry.

technical problem

The technical problem to be solved by the present invention is to provide a scanning device and a laser radar in response to the above-mentioned defects of the prior art, so as to solve the problem that the existing laser radar solution cannot meet the performance requirements of the industry.

Technical solutions

The technical solution adopted by the present invention to solve its technical problems is to provide a scanning device, which includes: a rotating bracket that can rotate around a rotating shaft; a mirror fixed on the rotating bracket; a magnetic piece fixed on the rotating bracket Top; a magnetic field generating mechanism to generate a magnetic field with a variable direction, the magnetic member is set in the magnetic field and moves back and forth under the action of the magnetic field to drive the rotating bracket to rotate back and forth.

Wherein, a preferred solution is that the rotating bracket further includes an extension part, and the magnetic member is arranged at an end of the extension part.

Among them, a preferred solution is that: an elastic reset member is arranged between the rotating bracket and the rotating shaft; or, the scanning device further includes a fixed bracket, and an elastic reset member is arranged between the fixed bracket and the rotating bracket.

Among them, a preferred solution is that: an elastic restoring member is provided between the extension part and the rotating shaft.

Among them, a preferred solution is that a mounting plate is provided on the extension part, and the elastic resetting member is arranged between the mounting plate and the rotating shaft.

Among them, a preferred solution is that the elastic recovery member is a spring structure.

Among them, a preferred solution is that the reflecting mirror and the magnetic member are arranged opposite to the two sides of the rotating support.

Wherein, the preferred solution is that the electromagnet assembly includes a ring-shaped iron core with a gap and a coil arranged around the ring-shaped iron core, and both ends of the coil are electrically connected to an external power source, and the ring iron An electromagnetic field is generated at the gap of the core, and the magnetic member is arranged at the gap.

Among them, a preferred solution is that the scanning device further includes a control unit, and controls the electromagnetic field direction of the electromagnet assembly according to a preset instruction to achieve periodic change, so that the rotating bracket is driven by the magnetic member to achieve a rotating reciprocating movement.

Among them, a preferred solution is that the scanning device further includes an angle detection unit to obtain the rotation angle of the rotating bracket.

Among them, a preferred solution is that the angle detection unit includes a first detection element and a fixed second detection element arranged on the rotating bracket, and obtains the angle of the rotating bracket according to the deviation of the first detection element and the second detection element. Rotation angle.

The technical solution adopted by the present invention to solve its technical problems is to provide a laser radar. The laser radar includes a laser assembly and a scanning device. The laser assembly at least includes a laser emitting head and a detector. The laser emitting head emits laser light. To the mirror of the scanning device and emit outward, and the detector receives the laser light emitted back from the mirror of the scanning device for detection.

Beneficial effect

The beneficial effect of the present invention is that compared with the prior art, the present invention has the advantages of small size, fast rotation speed and high efficiency by designing a scanning device and a laser radar, compared with a rotating scanning system driven by a motor. Compared with the traditional galvanometer scanning system, it has the advantages of lower cost, smaller size, lower power consumption, and better environmental adaptability. At the same time, compared with the MEMS system, it has a larger scanning area and a wider scanning angle range. Wider and closer to the practical advantages; further, the independent angle detection device can provide reliable and highly accurate real-time detection of the scanning angle of the galvanometer to meet the high-precision and high-reliability requirements of the laser radar for the scanning device and realize intelligent control.

Description of the drawings

The present invention will be further described below in conjunction with the accompanying drawings and embodiments. In the accompanying drawings:

Figure 1 is a schematic top view of the structure of the scanning device of the present invention;

2 is a schematic side view of the structure of the scanning device of the present invention;

Fig. 3 is a schematic top view of the structure of the rotating bracket of the present invention;

4 is a schematic side view of the structure of the rotating bracket of the present invention;

FIG. 5 is a schematic top view of the structure of the scanning device based on the angle detection unit of the present invention;

6 is a schematic side view of the structure of the scanning device based on the angle detection unit of the present invention;

Figure 7 is a schematic structural view of the electromagnet assembly of the present invention;

FIG. 8 is a schematic top view of the scanning device based on the electromagnet assembly of the present invention;

Figure 9 is a schematic diagram of the structure of the electromagnet assembly and the control unit of the present invention;

10 is a schematic diagram of the structure of the laser radar launching step of the present invention;

Figure 11 is a schematic diagram of the structure of the laser radar receiving step of the present invention.

The best mode of the invention

The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

As shown in Figures 1 and 2, the present invention provides a preferred embodiment of a scanning device. To

A scanning device includes a rotating support 110, a reflecting mirror 120, a magnetic member 130 and a magnetic field generating mechanism 200; wherein the rotating support 110 can rotate, the reflecting mirror 120 is fixed on the rotating support 110, and the magnetic member 130 is fixed on the rotating support. On the support 110, the magnetic field generating mechanism 200 generates a magnetic field 201 with a variable direction. The magnetic member 130 is set in the magnetic field 201 and moves back and forth under the action of the magnetic field 201 to drive the rotating support 110 to rotate back and forth.

Specifically, the reflector 120 is fixed on the rotating bracket 110 and rotates as the rotating bracket 110 rotates around the shaft 111. The scanning device further includes a magnetic member 130 arranged on the rotating bracket 110 and a magnetic member 130 130 is matched with the magnetic field generating mechanism 200, the magnetic member 130 is placed in the electromagnetic field 201 area of the magnetic field generating mechanism 200, and the magnetic field generating mechanism 200 generates the electromagnetic magnetic field 201 to move the magnetic member 130 after being energized. The support 110 is driven by the magnetic member 130 to rotate around the rotating shaft 111 to drive the mirror 120 to rotate.

The rotating shaft 111 is also connected to the base 300. The rotating shaft 111 is movable and fixed to the rotating bracket 110. As the rotating bracket 110 rotates, it rotates on the base 300 around the axis, or the rotating shaft 111 is fixed to the base 300 and the rotating bracket 110 and the rotating shaft 111 are movably arranged, and as the rotating support 110 rotates, it rotates around the axis of the rotating shaft 111. Both can be considered that the rotating bracket 110 rotates around the rotating shaft 111 driven by the magnetic member 130.

Specifically, the rotating support 110 can rotate around the rotating shaft 111 to reflect the laser beam incident on the reflector 120 to the outside, and the laser beam reflected from the outside is reflected back to the corresponding detection module through the reflector 120 to realize the laser Detect and realize scanning operation through the rotation of the mirror 120 to enlarge the scanning area and scanning direction to realize omnidirectional scanning detection. And, through the cooperation of the magnetic field generating mechanism 200 and the magnetic member 130, the electromagnetic field 201 area generated by the magnetic field generating mechanism 200, the electromagnetic field 201 area realizes the switching of the electromagnetic field direction in the rotation direction (horizontal direction), for example, the clockwise direction is positive The direction, the counterclockwise direction is the opposite direction, which is used to drive the magnetic member 130 in the electromagnetic field 201 area to move, so as to control the rotation direction and even the speed of the rotating support 110.

As shown in Figures 3 and 4, the present invention provides a preferred embodiment of a rotating bracket. To

The rotating bracket 110 further includes an extension 140, and the magnetic member 130 is arranged at the end of the extension 140. The magnetic member 130 can be arranged away from the rotating bracket 110 to prevent the rotating bracket 110 from colliding with the magnetic field generating mechanism 200.

The extension 140 can have any shape, which is intended to keep the magnetic member 130 away from the rotating body of the rotating bracket 110. At the same time, the structure of the magnetic field generating mechanism 200 can be optimized to satisfy the shape and structure of the extension 140.

Further, the reflecting mirror 120 and the magnetic member 130 are disposed on two sides of the rotating support 110 opposite to each other. In order to prevent the magnetic element 130 and the magnetic field generating mechanism 200 from interfering with and colliding with the mirror 120, the structure of the magnetic field generating mechanism 200 can be optimized, and the maximum reflection scanning range can be provided to avoid the obstruction of the extension 140 and the magnetic field generating mechanism 200.

Wherein, the two side surfaces provided on the rotating support 110 are preferably provided on two opposite sides. Of course, it can also be implemented not on two opposite sides, as long as the reflector 120 and the magnetic member 130 are set away from each other.

Further, a bearing 112 is also included between the rotating support 110 and the rotating shaft 111. The bearing 112 is sleeved on the rotating shaft 111 and connected to the rotating support 110 to assist rotation, improve the smoothness of rotation, and reduce the friction of rotation. Specifically, the bearing 112 is an important component in contemporary mechanical equipment, and its main function is to support the mechanical rotating body, reduce the friction coefficient during its movement, and ensure its rotation accuracy.

Wherein, the rotating support 110 rotates around the rotating shaft 111 through the bearing 112.

In this embodiment, the scanning device further includes an elastic recovery member 150 arranged between the rotating shaft 111 and the rotating bracket 110. After the electromagnetic field of the magnetic field generating mechanism 200 is disconnected by the elastic restoring member 150 during the rotation of the rotating bracket 110, it can be quickly restored to the position corresponding to the most original state of the elastic restoring member 150. If the reflecting mirror 120 is arranged opposite to the extension 140 On both sides of the rotating bracket 110, the reset position of the rotating bracket 110 is a position directly opposite to the magnetic field generating mechanism 200.

Further, a mounting plate 141 is provided on the extension 140, preferably at the end of the extension 140, and the magnetic member 130 is provided on the mounting plate 141. Of course, it can also be provided on the extension 140. The elastic recovery member 150 is respectively arranged between the rotating shaft 111 and the mounting plate 141. The elastic restoring member 150 is placed in a horizontal position and can be directly connected with the rotating shaft 111 and the mounting plate 141 to provide maximum elasticity for resetting.

Further, the scanning device further includes a fixed support (not shown in the drawings), and an elastic recovery member 150 arranged between the fixed support and the rotating support 110. Preferably, the scanning device includes a base 300, and the rotating shaft 111 Both the fixing bracket and the fixing bracket are arranged on the base 300.

Preferably, the elastic recovery member 150 is a spring structure. Through the self-recovery performance of the spring structure, the reset is realized. Of course, it can also be other elastic recovery members 150, such as shrapnel, plastic flexible strips, etc. The reset means that after the magnetic field generating mechanism 200 is powered off, the rotating bracket 110 is rotated back to the original position through the elastic recovery performance of the spring structure.

As shown in Figures 5 and 6, the present invention provides a preferred embodiment of an angle detection unit.

The scanning device further includes an angle detection unit to obtain the rotation angle of the rotating bracket 110.

In this embodiment, the angle detection unit includes a first detection element 162 and a fixed second detection element 161 arranged on the rotating bracket 110, and is based on the deviation between the first detection element 162 and the second detection element 161 The rotation angle of the rotating bracket 110 is obtained.

According to the deviation, the offset angle is obtained through related calculation formulas or analysis schemes, so as to obtain the rotation angle of the rotating bracket 110, thereby improving the self-control and dataability of the entire system.

Wherein, the first detection element 162 and the second detection element 161 can be implemented by light sensors, electromagnetic sensors, contact structure sensors, and the like.

Preferably, the first detecting member 162 is arranged on the rotating support 110, and the second detecting member 161 is arranged on a fixed rotating shaft.

As shown in Figures 7-9, the present invention provides a preferred embodiment of an electromagnet assembly.

The magnetic field generating mechanism 200 includes a toroidal core 210 with a gap 211 and a coil 220 arranged around the toroidal core 210. The two ends of the coil 220 are respectively electrically connected to an external power source, and are connected to the toroidal core after being energized. The electromagnetic field 201 is generated at the gap 211 of the 210, and the magnetic member 130 is arranged at the gap 211.

Specifically, when the coil 220 is energized, an electromagnetic field 201 is formed at the gap 211 of the toroidal core 210, and the direction of the electromagnetic field 201 can be changed by changing the direction in which the coil 220 is energized.

Among them, the magnetic member 130 is preferably a permanent magnet.

In this embodiment, the scanning device further includes a control unit 400 to control the direction of energization, and to control the direction of the electromagnetic field 201 of the magnetic field generating mechanism 200 according to preset instructions to achieve periodic changes, so as to drive the rotating bracket through the magnetic member 130 110 realizes the reciprocating movement of rotation.

As shown in Figures 10 and 11, the present invention provides a preferred embodiment of a lidar.

A laser radar. The laser radar includes a laser component and a scanning device. The laser component includes at least a laser emitting head 510 and a detector 520. The laser emitting head 510 emits laser light to the mirror 120 of the scanning device and emits it outward The detector 520 receives the laser light emitted from the mirror 120 of the scanning device for detection.

Provide two working modes of lidar.

During the emitting process, the laser emitting head 510 emits laser light to the mirror 120 of the scanning device and emits it outwards, and is incident on the corresponding object 600.

In the receiving process, when the outwardly emitted laser beam touches the corresponding object 600, it is reflected back to the scanning device to realize the detection function.

In the present invention, the scanning device and lidar are mainly used in fields such as unmanned driving sensing, 3-D surveying and mapping, and AGV navigation. When applied to unmanned driving and AGV, the lidar is generally installed on the top or side of the vehicle to detect targets in the corresponding direction.

The above are only the best embodiments of the present invention and are not used to limit the scope of the present invention. All equivalent changes or modifications made in accordance with the scope of the patent application of the present invention are covered by the present invention.

Claims

A scanning device, characterized by comprising:

Rotating bracket can rotate around a rotating shaft;

The reflector is fixed on the rotating bracket;

The magnetic part is fixed on the rotating bracket;

A magnetic field generating mechanism generates a magnetic field with a variable direction, and the magnetic member is arranged in the magnetic field with a variable direction and moves back and forth under the action of the magnetic field with a variable direction to drive the rotating bracket to rotate back and forth.
The scanning device according to claim 1, wherein the rotating bracket further comprises an extension part, and the magnetic member is arranged at an end of the extension part.
The scanning device according to claim 1, characterized in that: an elastic reset member is arranged between the rotating bracket and the rotating shaft; or, the scanning device further comprises a fixed bracket, and the fixed bracket and the rotating bracket are arranged between the There are elastic reset pieces.
3. The scanning device according to claim 2, wherein an elastic reset member is provided between the extension part and the rotating shaft.
4. The scanning device according to claim 4, wherein a mounting plate is provided on the extension part, and the elastic reset member is arranged between the mounting plate and the rotating shaft.
The scanning device according to any one of claims 3 to 5, wherein the elastic recovery member is a spring structure.
The scanning device according to claim 1, wherein the reflecting mirror and the magnetic member are arranged on two sides of the rotating support opposite to each other.
The scanning device according to claim 1, wherein the electromagnet assembly includes a ring-shaped iron core with a gap and a coil arranged around the ring-shaped iron core, and both ends of the coil are electrically connected to an external power source, respectively, And after energization, an electromagnetic field is generated at the gap of the annular iron core, and the magnetic member is arranged at the gap.
The scanning device according to claim 1 or 8, characterized in that: the scanning device further comprises a control unit, and controls the electromagnetic field direction of the electromagnet assembly according to the preset instruction to realize the periodic change, so as to drive the rotation by the magnetic member The bracket realizes the reciprocating movement of rotation.
The scanning device according to claim 1, wherein the scanning device further comprises an angle detection unit to obtain the rotation angle of the rotating bracket.
The scanning device according to claim 10, wherein the angle detection unit includes a first detection element and a fixed second detection element arranged on the rotating bracket, and the angle detection unit is based on the first detection element and the second detection element. To obtain the rotation angle of the rotating bracket.
A laser radar, characterized in that: the laser radar includes a laser assembly and the scanning device according to any one of claims 1 to 11, the laser assembly at least includes a laser emitting head and a detector, and the laser emitting head emits The laser light reaches the mirror of the scanning device and is emitted outward, and the detector receives the laser light emitted back from the mirror of the scanning device for detection.