Rotating polygonal mirror lidar systems, and calibration methods, devices, and systems thereof
The rotating device and calibration method for LiDAR systems address positional deviations and centrifugal forces, improving scanning accuracy and reducing noise, ensuring precise LiDAR performance.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-09-23
- Publication Date
- 2026-04-02
AI Technical Summary
LiDAR systems face issues such as deviations in channel positions due to manufacturing errors, leading to inaccurate point cloud results, and large polygonal mirrors experience centrifugal forces and vibrations at high rotational speeds, affecting scanning accuracy and noise levels.
A rotating device for LiDAR systems with a bearing and motor configuration that reduces vibration and noise, and a calibration method to correct channel angle errors, using a movable component and controller to align detection centers with calibration targets, and dynamic-balance components to maintain concentricity and reduce centrifugal forces.
Improves point cloud accuracy and scanning precision by reducing vibration and noise, while maintaining concentricity and reducing centrifugal forces, thereby enhancing LiDAR system performance.
Smart Images

Figure CN2025123335_02042026_PF_FP_ABST
Abstract
Description
ROTATING POLYGONAL MIRROR LIDAR SYSTEMS, AND CALIBRATION METHODS, DEVICES, AND SYSTEMS THEREOFCROSS-REFERENCE
[0001] This application claims priority to Chinese Patent Application No. 202411342097.4, filed on September 24, 2024, and claims priority to U.S. Application No. US 19 / 214,227 filed on May 21, 2025 which claims priority to Chinese Patent Application No. 202411342097.4 filed on September 24, 2024, and claims priority to Chinese Patent Application No. 202411342139.4 filed on September 24, 2024, and claims priority to U.S. Application No. US 19 / 256,615 filed on July 1, 2025 which claims priority from Chinese Patent Application No. 202411342139.4 filed on September 24, 2024, the entire contents of which are incorporated herein by reference.BACKGROUND
[0002] LiDAR acquires information of a calibration target by emitting laser pulses towards the calibration target and receiving the reflected pulses, presenting the acquired information in the form of point clouds. Each point in the point cloud corresponds to a channel of the LiDAR, and the channels of the LiDAR are arranged according to pre-designed positions. However, due to errors in the manufacturing process and production techniques, after actual production is completed, there may be deviations between the actual positions of the LiDAR channels and their pre-designed positions. Consequently, the obtained LiDAR point cloud results may deviate from the true LiDAR point cloud results, leading to deviations in the detection or measurement results of the LiDAR.
[0003] Moreover, LiDAR systems often include a polygonal mirror and corresponding rotating device thereof to reflect and scan the LiDAR beam across an environment. Commonly available LiDAR scanners on the market are either large in size with low rotational speed, or small in size with high rotational speed in terms of dimensions and rotational speed of the polygonal mirror. However, when attempting to utilize a large polygonal mirror at high rotational speed, excessive centrifugal forces can easily damage the polygonal mirror and rotating device thereof. Moreover, by utilizing a large polygonal mirror in a LiDAR scanner, it is difficult to achieve good concentricity in the assembly of the motor and a corresponding polygonal mirror. Lastly, the polygonal mirror and rotating device thereof are prone to vibration and noise at high rotational speeds that may also introduce noise or a deviation into the acquired point cloud of a surrounding environment.SUMMARY
[0004] In view of the above shortcomings of prior LiDAR scanner systems, provide herein are a calibration method, controller, calibration device, and system for adjusting or correcting LiDAR system channel angle error to improve the point cloud accuracy of a LiDAR system in recreating its surrounding environment. Moreover, the present application provides a rotating device of a polygonal mirror of a LiDAR system, which reduces vibration and noise of the polygonal mirror when rotating at high rotational speeds. Provided herein are devices, and methods of decreasing centrifugal forces upon the rotating polygonal mirror that also maintain concentricity between the rotating motor and polygonal mirror.
[0005] In an aspect, the disclosure provides a rotating device for Light Detection and Ranging (LiDAR) system comprising: a motor configured to drive an optical component to have a rotary movement; and a bearing disposed between a first bearing support and a second bearing support, wherein the motor and the optical component are sleeved onto the bearing and wherein the motor is configured to drive the optical component via the bearing thereby reducing vibration and noise or centrifugal force. In some embodiments, the first bearing support and the second bearing support may be oppositely arranged with respect to each other. In some embodiments, a stator of the motor may be connected to a surface of the first bearing support facing toward the second bearing support. In some embodiments, the motor may comprise an outer rotor and wherein the outer rotor is located at an end surface of the motor facing away from the first bearing support. In some embodiments, the optical component may comprise a polygonal mirror comprising a first end surface, and a second end surface opposite to the first end surface. In some embodiments, the first end surface may be connected to the outer rotor through a plurality of connecting elements. In some embodiments, an end of the bearing may be connected to the second bearing support, and wherein another end of the bearing may be configured to pass through the second end surface and the first end surface of the polygonal mirror and connected to the motor. In some embodiments, the outer rotor and the polygonal mirror may be respectively sleeved on the bearing. In some embodiments, the first bearing support and the second bearing support may be connected to a base. In some embodiments, the first bearing support and the second bearing support may be parallelly arranged, and respectively connected to a same end surface of the base. In some embodiments, the polygonal mirror and the outer rotor respectively may have a gap with the base. In some embodiments, an end surface of the outer rotor may be connected to a motor base facing toward the first bearing support, and wherein the motor base is connected to the first bearing support. In some embodiments, the optical component may comprise a polygonal mirror formed by a plurality of mirrors surrounding edges of a first end surface and a second end surface of the optical component, wherein each mirror is connected to an adjacent mirror, and parallel to the bearing. In some embodiments, the plurality of connecting elements may be symmetrically arranged around the bearing. In some embodiments, the optical component may be configured to direct light beams emitted by the LiDAR. In some embodiments, the rotating device may further comprise an encoder located on a surface of the second bearing support facing away from the first bearing support, wherein the encoder may be configured to measure positions or rotating speed of the motor which are used to generate control instructions for directing light beams. In some embodiments, the control instructions may be transmitted to the motor to adjust operating data of the motor. In some embodiments, the operating data may comprise rotational speed data representing a rotational speed of the motor, and position data representing a rotational position of the motor. In some embodiments, the rotating device may comprise a first dynamic-balance component, wherein the first dynamic-balance component comprises a first dynamic-balance surface facing toward the first bearing support, and a second dynamic-balance surface facing away from the first dynamic-balance surface. In some embodiments, the first dynamic-balance surface may be in direct contact with an end surface of a rotor of the motor facing toward the second bearing support. In some embodiments, along an axis direction perpendicular to the first dynamic-balance component, a cross-sectional area of the first dynamic-balance surface may be smaller than a cross-sectional area of the second dynamic-balance surface. In some embodiments, the first dynamic-balance component may further comprise a first sidewall extending toward the second bearing support around an edge of the first dynamic-balance surface, a second sidewall extending toward the first bearing support around an edge of the second dynamic-balance surface, and a first counterweight groove formed by the second dynamic-balance surface, an outer wall of the first sidewall, and an inner wall of the second sidewall, wherein the first counterweight groove accommodates a plurality of first counterweight elements. In some embodiments, the rotating device may further comprise a second dynamic-balance component located on a surface of the second bearing support facing away from the optical component and wherein the second dynamic-balance component has a gap with the second bearing support. In some embodiments, the second dynamic-balance component may be provided with a third dynamic-balance surface facing toward the second bearing support and a fourth dynamic-balance surface facing away from the third dynamic-balance surface. In some embodiments, along an axis direction perpendicular to the second dynamic-balance component, a cross-sectional area of the fourth dynamic-balance surface may be smaller than a cross-sectional area of the third dynamic-balance surface. In some embodiments, the second dynamic-balance component may further comprise a third sidewall extending away from the second bearing support around the edge of the third dynamic-balance surface, a fourth sidewall extending toward the second bearing support around the edge of the fourth dynamic-balance surface, and a second counterweight groove formed by the fourth dynamic-balance surface, an outer wall of the third sidewall, and an inner wall of the fourth sidewall, wherein the second counterweight groove accommodates a plurality of second counterweight elements. In some embodiments, the rotary movement may be at a speed of at least 300 rotations per minute (rpm) .
[0006] In an aspect, the disclosure provides a Light Detection and Ranging (LiDAR) system comprising: an optical component; and a rotating device configured to drive the optical component to have a rotary movement, wherein the rotating device comprises: a bearing disposed between a first bearing support and a second bearing support, and a motor configured to drive the optical component via the bearing thereby reducing vibration and noise or centrifugal force, wherein the motor and the optical component are sleeved onto the bearing. In some embodiments, the first bearing support and the second bearing support may be oppositely arranged with respect to each other. In some embodiments, a stator of the motor may be connected to a surface of the first bearing support facing toward the second bearing support. In some embodiments, the motor may comprise an outer rotor and wherein the outer rotor is located at an end surface of the motor facing away from the first bearing support. In some embodiments, the optical component may comprise a polygonal mirror comprising a first end surface, and a second end surface opposite to the first end surface. In some embodiments, the first end surface may be connected to the outer rotor through a plurality of connecting elements. In some embodiments, an end of the bearing may be connected to the second bearing support, and wherein another end of the bearing may be configured to pass through the second end surface and the first end surface of the polygonal mirror and connected to the motor. In some embodiments, the outer rotor and the polygonal mirror may be respectively sleeved on the bearing. In some embodiments, the first bearing support and the second bearing support may be connected to a base. In some embodiments, the first bearing support and the second bearing support may be parallelly arranged, and respectively connected to a same end surface of the base. In some embodiments, the polygonal mirror and the outer rotor respectively may have a gap with the base. In some embodiments, an end surface of the outer rotor may be connected to a motor base facing toward the first bearing support, and wherein the motor base may be connected to the first bearing support. In some embodiments, the optical component may comprise a polygonal mirror formed by a plurality of mirrors surrounding edges of a first end surface and a second end surface of the optical component, and wherein each mirror may be connected to an adjacent mirror, and parallel to the bearing. In some embodiments, the plurality of connecting elements may be symmetrically arranged around the bearing. In some embodiments, the optical component may be configured to direct light beams emitted by the LiDAR. In some embodiments, the rotating device may further comprise an encoder located on a surface of the second bearing support facing away from the first bearing support, and wherein the encoder may be configured to measure positions or rotating speed of the motor which are used to generate control instructions for directing light beams. In some embodiments, the control instructions may be transmitted to the motor to adjust operating data of the motor. In some embodiments, the operating data may comprise rotational speed data representing a rotational speed of the motor, and position data representing a rotational position of the motor. In some embodiments, the LiDAR system may comprise a first dynamic-balance component, wherein the first dynamic-balance component may comprise a first dynamic-balance surface facing toward the first bearing support, and a second dynamic-balance surface facing away from the first dynamic-balance surface. In some embodiments, the first dynamic-balance surface may be in direct contact with an end surface of a rotor of the motor facing toward the second bearing support. In some embodiments, along an axis direction perpendicular to the first dynamic-balance component, a cross-sectional area of the first dynamic-balance surface may be smaller than a cross-sectional area of the second dynamic-balance surface. In some embodiments, the first dynamic-balance component may comprise a first sidewall extending toward the second bearing support around an edge of the first dynamic-balance surface, a second sidewall extending toward the first bearing support around an edge of the second dynamic-balance surface, and a first counterweight groove formed by the second dynamic-balance surface, an outer wall of the first sidewall, and an inner wall of the second sidewall, wherein the first counterweight groove may accommodate a plurality of first counterweight elements. In some embodiments, the rotating device may further comprise a second dynamic-balance component located on a surface of the second bearing support facing away from the optical component, and wherein the second dynamic-balance component may have a gap with the second bearing support. In some embodiments, the second dynamic-balance component may be provided with a third dynamic-balance surface facing toward the second bearing support and a fourth dynamic-balance surface facing away from the third dynamic-balance surface. In some embodiments, along an axis direction perpendicular to the second dynamic-balance component, a cross-sectional area of the fourth dynamic-balance surface may be smaller than a cross-sectional area of the third dynamic-balance surface. In some embodiments, the second dynamic-balance component may comprises a third sidewall extending away from the second bearing support around the edge of the third dynamic-balance surface, a fourth sidewall extending toward the second bearing support around the edge of the fourth dynamic-balance surface, and a second counterweight groove formed by the fourth dynamic-balance surface, an outer wall of the third sidewall, and an inner wall of the fourth sidewall, wherein the second counterweight groove may accommodate a plurality of second counterweight elements. In some embodiments, the rotary movement may be at a speed of at least 300 rpm.
[0007] In an aspect, the disclosure provides a calibration device for calibrating channel angular errors for a LiDAR optical engine comprising: a movable component configured to drive the LiDAR optical engine to deflect relative to a calibration target in one or more directions; and a controller operably coupled to the movable component, wherein the controller comprises a memory, configured to store computer programs and a processor, configured to execute the computer programs to perform a calibration method comprising: (a) controlling the movable component to move to align a detection center of the LiDAR optical engine with a center of the calibration target, (b) selecting a channel from a plurality of the channels in the LiDAR optical engine to be calibrated and activating an emitter of the selected channel to project a real light spot, (c) controlling the movable component to move at a deflection angle in the one or more directions to align the selected channel with the center of the calibration target by aligning the real light spot with the center of the calibration target, and (d) determining an offset angle for the selected channel based at least in part on the deflection angle, and calibrating the selected channel based on the offset angle. In some embodiments, the detection center of the LiDAR optical engine may be a center of a detection area of the plurality of the channels. In some embodiments, the center of the calibration target may be represented by a reference marker on the calibration target. In some embodiments, the one or more directions may comprise a horizontal direction and a vertical direction. In some embodiments, the deflection angle in the one or more directions may comprise a horizontal deflection angle or a vertical deflection angle. In some embodiments, the calibration method may further comprise selecting a next channel from the plurality of channels and repeating (c) and (d) . In some embodiments, the offset angle may be stored in a lookup table for calibrating the selected channel. In some embodiments, the deflection angle may be based on a command generated by the controller.
[0008] In an aspect, the disclosure provides a calibration device for calibrating channel angular errors for a LiDAR optical engine comprising: a movable component configured to drive the LiDAR optical engine to deflect relative to a calibration target in one or more directions; and a controller operably coupled to the movable component, wherein the controller comprises a memory, configured to store computer programs and a processor, configured to execute the computer programs to perform a calibration method comprising: controlling the movable component to move to align a detection center of the LiDAR optical engine with a center of the calibration target, selecting one or more channels from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of each of the selected one or more channels to project a real light spot to the calibration target, acquiring an image of the calibration target containing one or more of the real light spots, with an imaging acquisition device, and determining an offset angle for each of the selected one or more channels based at least in part on an offset position between a real light spot and a respective reference spot in the acquired image. In some embodiments, the one or more channels may be activated simultaneously, and wherein the acquired image contains one or more of the real light spots emitted simultaneously. In some embodiments, the one or more channels may be activated sequentially, wherein the acquired image may be an image containing a real light spot emitted from a single channel, and wherein one or more of the images may be superimposed to generate a superimposed image. In some embodiments, the superimposed image may be analyzed to determine the offset angle of each of the selected one or more channels. In some embodiments, the offset position may comprise an offset of the real light spot relative to the respective reference spot measured in the acquired image a horizontal direction or a vertical direction. In some embodiments, the offset angle may be determined based at least in part on the offset position and a known spatial relationship between the calibration target, the LiDAR optical engine, and the image acquisition device. In some embodiments, the one or more directions may comprise a horizontal direction and a vertical direction. In some embodiments, the offset angle may be stored in a lookup table for calibrating the selected channel.
[0009] In an aspect, the disclosure provides a method of calibrating channel angular errors for a LiDAR optical engine, comprising: (a) controlling a moveable component to move in one or more directions to align a detection center of the LiDAR optical engine with a center of a calibration target; (b) selecting a channel from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of the selected channel to project a real light spot; (c) controlling the movable component to move at a deflection angle in the one or more directions to align the selected channel with the center of the calibration target by aligning the real light spot with the center of the calibration target; and (d) determining an offset angle for the selected channel based at least in part on the deflection angle, and calibrating the selected channel based on the offset angle. In some embodiments, the detection center of the LiDAR optical engine may be a center of a detection area of the plurality of the channels. In some embodiments, the center of the calibration target may be represented by a reference marker on the calibration target. In some embodiments, the one or more directions may comprise a horizontal direction or a vertical direction. In some embodiments, the deflection angle in the one or more directions may comprise a horizontal deflection angle or a vertical deflection angle. In some embodiments, the calibration method may comprises selecting a next channel from the plurality of channels and repeating (c) and (d) . In some embodiments, the offset angle may be stored in a lookup table for calibrating the selected channel. In some embodiments, the deflection angle may be based on a command generated by the controller.
[0010] In an aspect, the disclosure provides a method of calibrating channel angular errors for a LiDAR optical engine, comprising: controlling a movable component to move in one or more directions to align a detection center of the LiDAR optical engine with a center of the calibration target; selecting one or more channels from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of each of the selected one or more channels to project a real light spot to the calibration target; acquiring an image of the calibration target containing one or more of the real light spots with an imaging acquisition device; and determining an offset angle for each of the selected one or more channels based at least in part on an offset position between a real light spot and a respective reference spot in the acquired image. In some embodiments, the one or more channels may be activated simultaneously, and wherein the acquired image may contain one or more of the real light spots emitted simultaneously. In some embodiments, the one or more channels may be activated sequentially, wherein the acquired image may be an image containing a real light spot emitted from a single channel, and wherein one or more of the images are superimposed to generate a superimposed image. In some embodiments, the superimposed image may be analyzed to determine the offset angle of each of the selected one or more channels. In some embodiments, the offset position may comprise an offset of the real light spot relative to the respective reference spot measured in the acquired image in a horizontal direction or in a vertical direction. In some embodiments, the offset angle may be determined based at least in part on the offset position and a known spatial relationship between the calibration target, the LiDAR optical engine, and the image acquisition device. In some embodiments, the one or more directions may comprise a horizontal direction and a vertical direction. In some embodiments, the offset angle may be stored in a lookup table for calibrating the selected channel.BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
[0012] FIG. 1 illustrates a schematic structural diagram of a rotating device of a polygonal mirror, as described in embodiments herein.
[0013] FIG. 2 illustrates a schematic structural diagram of a LiDAR optical engine, as described in embodiments herein.
[0014] FIG. 3 shows a flowchart of a calibration method for LiDAR optical engine channel angle errors in accordance with a first embodiment, as described in embodiments herein.
[0015] FIGs. 4-5 show a sub-flowchart of a calibration method for LiDAR optical engine channel angle errors, as described in embodiments herein.
[0016] FIG. 6 illustrates a schematic diagram of electrical connections of a calibration device for LiDAR channel angle errors, as described in embodiments herein.
[0017] FIG. 7 illustrates a schematic diagram of the structure of a calibration system for LiDAR optical engine channel angle errors, as described in embodiments herein.
[0018] FIG. 8 shows an image of a calibration target illuminated by a channel of the LiDAR optical engine to be calibrated, as described in embodiments herein.
[0019] FIG. 9 shows an image of a calibration target illuminated by a plurality of channels of a LiDAR optical engine to be calibrated, as described in embodiments herein.
[0020] FIG. 10 shows a graphical distribution of channels of a LiDAR optical engine, as described in embodiments herein.
[0021] FIGS. 11A-11B show a bottom view (FIG. 11A) and a right perspective view (FIG. 11B) of an exemplary polygonal mirror design, as described in embodiments herein.
[0022] FIG. 12 is an example illustration of a dynamic-balance component, as described in embodiments herein. INCORPORATION BY REFERENCE
[0023] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.DETAILED DESCRIPTION
[0024] Unless defined otherwise, all terms of art, notations and other technical and scientific terms or terminology used herein are intended to have the same meaning as is commonly understood by one of ordinary skill in the art to which the claimed subject matter pertains. In some cases, terms with commonly understood meanings are defined herein for clarity and / or for ready reference, and the inclusion of such definitions herein should not necessarily be construed to represent a substantial difference over what is generally understood in the art.
[0025] Throughout this application, various embodiments may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the disclosure. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.
[0026] As used in the specification and claims, the singular forms “a, ” “an, ” and “the” include plural references unless the context clearly dictates otherwise. For example, the term “asample” includes a plurality of samples, including mixtures thereof.
[0027] As used herein, the term “about” a number refers to that number plus or minus 10%of that number. The term “about” a range refers to that range minus 10%of its lowest value and plus 10%of its greatest value.
[0028] Use of absolute or sequential terms, for example, “will, ” “will not, ” “shall, ” “shall not, ” “must, ” “must not, ” “first, ” “initially, ” “next, ” “subsequently, ” “before, ” “after, ” “lastly, ” and “finally, ” are not meant to limit scope of the present embodiments disclosed herein but as exemplary.
[0029] The terms “first, ” “second, ” “third, ” “fourth, ” if any, in the specification, claims and drawings of this application are configured to distinguish similar objects but need not be configured to describe any particular order or sequence of priorities. It should be understood that the data used here are interchangeable where appropriate, in other words, the embodiments described can be implemented in order other than what is illustrated or described here. In addition, the terms “include” and “have” and any variation of them, can encompass other things. For example, processes, methods, systems, products, or equipment that comprise a series of steps or units need not be limited to those clearly listed but may include other steps or units that are not clearly listed or are inherent to these processes, methods, systems, products, or equipment.
[0030] It is to be noted that the references to “first, ” “second, ” etc. in the invention are for descriptive purpose only and neither be construed or implied the relative importance nor indicated as implying the number of technical features. Thus, feature defined as “first” or “second” can explicitly or implicitly include one or more such features. In addition, technical solutions between embodiments may be integrated, but only on the basis that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or impossible to be realized, such combination of technical solutions shall be deemed to be non-existent and not within the scope of protection required by the invention. LiDAR System
[0031] In reference to FIG. 1, a schematic structural diagram of a rotating device for a Light Detection and Ranging (LiDAR) system comprising a polygonal mirror, as described in some embodiments herein, is illustrated. In some embodiments, the LiDAR system may comprise: an optical component; and a rotating device configured to drive the optical component to have a rotary movement, where the rotating device comprises: a bearing disposed between a first bearing support and a second bearing support, and a motor configured to drive the optical component via the bearing thereby reducing vibration and noise or centrifugal force. In some embodiments, the motor and the optical components may be sleeved onto the bearing.
[0032] In some embodiments, the rotating device for the LiDAR system may comprise: a motor configured to drive an optical component (e.g., a polygonal mirror) to have a rotary movement; and a bearing disposed between a first bearing support and a second bearing support, where the motor and the optical component are sleeved onto the bearing and where the motor is configured to drive the optical component via the bearing thereby reducing vibration and noise or centrifugal force. In some cases, the rotary movement may comprise a speed of at least about 10 rpm, 20 rpm, 50 rpm, 100 rpm, 150 rpm, 200 rpm, 250pm, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, 1200 rpm, 1300 rpm, 1400 rpm, 1500 rpm, or 1600 rpm. A rotating device 10 of a polygonal mirror 3 may rotate the polygonal mirror in a LiDAR optical engine to direct or steer a LiDAR optical engine one or more LiDAR beams. In some cases, the LiDAR system may emit light beams from, off of, or through the polygonal mirror 3 to achieve multi-field-of-view scanning of an external environment adjacent or surrounding a LiDAR system. In some cases, the rotating device 10 can reduce the centrifugal force produced by a rotating polygonal mirror 3. In some instances, the rotating device 10 may reduce the vibration and noise produced during high-speed rotation, thereby improving the scanning and measurement accuracy of the LiDAR system.
[0033] As shown in FIG. 1, the rotating device 10 may comprise a bearing support 1, a motor, an optical component (e.g., a polygonal mirror 3) , or any combination thereof. In some cases, the optical component may be configured to direct light beams emitted by the LiDAR system. The bearing support 1 may comprise a first bearing support 11 and a second bearing support 12. In some cases, the first bearing support 11 and the second bearing support are oppositely arranged with respect to each other. In some embodiments, the bearing support 1 may further comprise a base 14. The first bearing support 11 and the second bearing support 12 may be arranged in parallel. In some cases, the first bearing support 11 and the second bearing support 12 may be coupled or connected to an end surface of the base 14. The base 14 may be provided with a mounting portion to facilitate the installation of the rotating device 10 on the LiDAR optical engine. The base 14 may comprise an end surface corresponding to the installation position of the polygonal mirror 3 within the LiDAR optical engine to save material costs when installing the rotating device 10. In some cases, the polygonal mirror 3 and the motor rotor 21 may have a gap with the base 14 to ensure smooth rotation of the motor components and the polygonal mirror 3. In some cases, a shaft or rod may be coupled to the motor rotor 21, motor base 22, bearing 13, polygonal mirror 3, or any combination thereof components. In some cases, the shaft or rod may be inserted through the length of the motor rotor 21, motor base 22, bearing 13, polygonal mirror 3, or any combination thereof components. In some cases, the polygonal mirror 3 may comprise a mounting interface 16 (as shown in FIGS. 11A-11B) , e.g., a tubular or cylindrical mounting interface through which the shaft or rod may be inserted through to couple to the polygonal mirror 3.
[0034] In some embodiments, the motor can be an outer rotor permanent magnet synchronous motor that may drive the polygonal mirror 3 to achieve rotation speed, e.g., of at least about 300 rpm. In some cases, a stator of the motor may be connected to a surface of the first bearing support 11 facing toward the second bearing support 12. In some cases, an end surface of the motor facing away from the first bearing support 11 may be provided with a motor rotor 21. In some embodiments, the motor may comprise a motor base 22. The motor base 22 may be connected to an end surface of the motor rotor 21 facing toward the first bearing support 11. The motor may be connected to the first bearing support 11 through the motor base 22. In some cases, the motor may comprise an outer rotor, where the outer rotor is located at an end surface of the motor facing away from the first bearing support 11.
[0035] In some embodiments, the motor may comprise a motor-rotor hub 23. The motor-rotor hub 23 may be mounted around an outer periphery of the motor rotor 21 to limit the rotation space of the motor rotor 21 when driven to rotate by the motor. The motor-rotor hub 23 may be in direct contacted, adjacent, or not in direct contacted to the motor rotor 21. In some cases, along an inner wall of the motor-rotor hub 23, one or more damping components made of vibration damping material may be disposed between the motor-rotor hub 23 and the outer periphery of the motor rotor 21, the contact between the motor-rotor hub 23 and the motor rotor 21, or a combination thereof. The one or more damping components may further reduce vibration and noise when the motor rotor 21 rotates the polygonal mirror 3. Alternatively, the one or more damping components may be located on an outer housing of the LiDAR system.
[0036] In some embodiments, the motor base 22 may be releasably coupled to the first bearing support 11 to facilitate the disassembly and subsequent maintenance of the rotating device 10. In some embodiments, the rotating device 10, the motor base 22, the first bearing support 11, or a combination thereof, can be integrated into a single system or unit to reduce the installation components required for the LiDAR optical engine and the rotating device 10, thereby saving material costs.
[0037] In some cases, other components of the rotating device 10 can reduce the centrifugal force generated by the motor. In some cases, the polygonal mirror 3 may comprise a first end surface and a second end surface opposite to the first end surface, as shown in FIGS. 11A-11B. In some cases, the polygonal mirror 3 may comprise one or more cavities 15 that may be provided throughout a portion of the length of the polygonal mirror 3 or through an entire length of the polygonal mirror 3. In some cases, the one or more cavities 15 of the polygonal mirror 3 may reduce the weight of the polygonal mirror 3, thereby reducing the moment of inertia of the polygonal mirror 3 such that the polygonal mirror can rotate with speeds of at least about 300 rpm with reduced torque and vibrations. In some cases, the first end surface may be connected to the motor rotor 21 through a plurality of connecting elements 31. In some cases, the first end surface may be connected or coupled to the outer rotor through a plurality of connecting elements. In some cases, the connecting element (s) 31 may comprise a material of aluminum alloy. In some cases, the connecting elements 31 may be made of aluminum alloy 6061-T6. In some cases, the connecting elements 31 may securely fasten the polygonal mirror 3 to the motor rotor hub 23. A bearing 13 may be disposed between the first bearing support 11 and the second bearing support 12. An end of the bearing 13 may be connected to the second bearing support 12. In some cases, another end of the bearing 13 may pass through the second end surface and the first end surface to connect to the motor, such that the motor rotor 21 and the polygonal mirror 3 are respectively sleeved on the bearing 13. In some cases, the outer rotor of the motor and the polygonal mirror 3 may be respectively sleeved on the bearing 13. In some cases, the position where the other end of the bearing 13 is connected to the motor may comprise an end surface of the motor base 22 facing the motor rotor 21, an end surface of the motor base 22 away from the motor rotor 21, or positions inside the motor base 22. In some cases, the motor may drive the motor rotor 21 to rotate when operating, thereby driving the bearing 13 to rotate and in turn causing the polygonal mirror 3 to rotate around the bearing 13.
[0038] In some embodiments, the other end of the bearing 13 can also pass through the motor base 22 to connect to the first bearing support 11, to increase support of the bearing support 1 to the motor rotor 21 and reduce or avoid deviation in the position of the polygonal mirror 3 due to deformation of both ends of the bearing 13 after high-speed rotation. If such deviation in the position of the polygonal mirror is not reduced such deviations may cause errors in the light beams emitted by the LiDAR optical engine through the polygonal mirror 3 to the environment adjacent or surround the LiDAR optical engine, thereby affecting the scanning accuracy and measurement accuracy of the LiDAR optical engine.
[0039] In some embodiments, the optical component of the LiDAR optical engine may comprise a polygonal mirror 3. In some instances, the polygonal mirror 3 may be formed by a plurality of facets of mirrors (e.g., facets 32 in FIG. 1) surrounding the edges of the first end surface and the second end surface of the optical component, as shown in FIGS. 11A-11B. In some cases, each mirror 32 may be connected to an adjacent mirror 32 thereof, and parallel to the bearing 13. In some cases, the plurality of connecting elements 31 may be symmetrically arranged around the bearing 13 to improve the stability of the connection between the motor rotor 21 and the polygonal mirror 3, thereby improving the concentricity of the polygonal mirror 3 relative to the rotating device 10 during rotation. In some cases, the plurality of mirrors 32 may be symmetrically arranged around the bearing 13. The plurality of connecting elements 31 may be arranged according to the arrangement direction of the plurality of mirrors 32 in the polygonal mirror 3 to improve the stability of the polygonal mirror 3 in the rotating device 10, thereby maintaining concentricity of the rotating device 10 during high-speed rotation.
[0040] In some embodiments, the first bearing support 11 and the second bearing support 12, combined with the bearing 13 and the base 14, improve the support for other components in the rotating device 10, avoiding measurement errors due to deformation of the bearing 13, that may occur at both ends of the bearing 13 during high-speed rotation of the rotating device 10. In some embodiments, the LiDAR system may emit light beams away from the LiDAR system into a surrounding environment external to the LiDAR system through the polygonal mirror 3.
[0041] In some embodiments, the rotating device 10 may comprise an encoder 4. The encoder 4 may be provided on a surface of the second bearing support 12 facing away from the first bearing support 11. In some cases, the encoder 4 may be configured to measure one or more positions, one or more rotating speeds, or a combination thereof, of the motor. In some cases, the encoder may comprise an optical encoder. In some cases, the optical encoder may comprise a photoelectric encoder. In some instances, the one or more positions, one or more rotating speeds, or a combination thereof, may be used to generate control instructions for directing light beams of the LiDAR system. The encoder 4 may be configured to generate control instructions based on the LiDAR system light beams and send or transmit the control instructions to the motor to adjust operating data of the motor, such that the motor drives the motor rotor 21 to rotate according to the operating data. The operating data may comprise rotational speed data representing a rotational speed of the motor, position data representing a rotational position of the motor, or a combination thereof. The encoder 4 may be capable of converting input analog signals and / or digital signals into corresponding output signals and generating corresponding control instructions based on the output signals to feed back to the rotating device 10 of the LiDAR system, thereby controlling the rotation of the polygonal mirror 3. In some cases, the encoder 4 may generate output signals based on the LiDAR system output beam, the spot formed by the beam, signals corresponding to the beam and / or the spot, or any combination thereof, where the encoder generates control instructions based on the output signals. In some cases, the control instructions may comprise speed commands for adjusting the rotational speed of the motor. In some cases, after generating the control instructions, the encoder 4 may send the control instructions to the motor to control the current rotational speed of the motor. In some embodiments, the control instructions may comprise one or more position commands for adjusting the rotational position of the motor. In some cases, after generating the control instructions, the encoder 4 may send the control instructions to the motor to control the current rotational speed and / or rotational position of the motor.
[0042] In some cases, when the components within the rotating device 10, described herein, rotate at speeds (e.g., at least about 10 rpm, 20 rpm, 50 rpm, 100 rpm, 150 rpm, 200 rpm, 250pm, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, 1200 rpm, 1300 rpm, 1400 rpm, 1500 rpm, 1600 rpm, etc. ) driven by the motor, corresponding dynamic balancing may be utilized to avoid or reduce deviation of the rotating components that may occur when rotating at high speeds.
[0043] In some embodiments, the rotating device 10 comprises a first dynamic-balance component 5. The first dynamic-balance component 5 may comprise a cylindrical shape as a whole. In some cases, the opposite end faces of the first dynamic-balance component 5 may comprise one or more grooves 13 (as shown in FIG. 12) with a predetermined dimension and shape (e.g., predetermined axial depth) complementary to a mating structures on other components in the rotation device thereby facilitating the installation of the first dynamic-balance component 5 with other components in the rotating device 10 without additional fastening means. In some cases, the one or more grooves 13 may maintain concentricity of the rotating device 10 during high-speed rotation. In some cases, the first dynamic-balance component 5 may be provided with a first dynamic-balance surface 51 facing toward the first bearing support 11, and a second dynamic-balance surface 52 facing away from the first dynamic-balance surface 51. In some cases, the first dynamic-balance surface 51 may directly contact an end face of the motor rotor 21 facing toward the second bearing support 12. In some cases, the first dynamic-balance surface 51 may comprise a groove with an axial depth to facilitate contact between the end face of the motor rotor 21 facing toward the second bearing support 12 and the first dynamic-balance surface 51. Along an axis direction perpendicular to the first dynamic-balance component 5, a cross-sectional area of the first dynamic-balance surface 51 may be less than or smaller than a cross-sectional area of the second dynamic-balance surface 52.
[0044] In some cases, to enable the rotating device 10 to maintain dynamic balancing at rotational speeds, e.g., of at least about 300 rpm, the rotating device 10 may achieve dynamic balancing of the motor rotor 21 by adding counterweight elements to the first dynamic-balance component 5. In some cases, the first dynamic-balance component 5 may comprises a first sidewall extending toward the second bearing support 12 around the edge of the first dynamic-balance surface 51, a second sidewall extending toward the first bearing support 11 around the edge of the second dynamic-balance surface 52, a first counterweight groove 53 formed by surrounding the second dynamic-balance surface 52, an outer wall of the first sidewall, an inner wall of the second sidewall, or any combination thereof. The first counterweight groove 53 may accommodate a plurality of first counterweight elements to achieve dynamic balancing of the rotating device 10 at rotational speeds of e.g., at least about 300 rpm. The first counterweight elements can be adapted according to the material of the first counterweight groove 53.
[0045] In some cases, the material of the first counterweight groove 53 may comprise photoelectric materials, magneto-electric materials, metallic materials. In some cases, the methods for dynamic balancing of the motor rotor 21 comprise photoelectric methods, magneto-electric methods, weight adjustment methods, or any combination thereof. In some cases, the material of the first counterweight element (s) may comprise but is not limited to metals, gels, photoelectric materials, or any combination thereof.
[0046] In some embodiments, based on the dynamic balancing of the motor rotor 21, the rotating device 10 may perform dynamic balancing of the encoder 4 to improve the accuracy of the data input to the encoder 4 and further improve the precision of the control commands outputted by the encoder 4 compared to if no dynamic balancing of the encoder 4 were performed. In some cases, the rotating device 10 may comprises a second dynamic-balance component 6. The second dynamic-balance component 6 may be located or provided on a surface of the second bearing support 12 facing away from the optical component, e.g., a polygonal mirror 3. In some instances, there may be a gap between the second dynamic-balance component 6 and the second bearing support 12. The second dynamic-balance component 6 may comprise a cylindrical shape as a whole. The shapes and / or sizes of the first dynamic-balance component 5 and the second dynamic-balance component 6 can be equal or unequal. The second dynamic-balance component 6 may be provided with a third dynamic-balance surface 61 facing toward the second bearing support 12, and a fourth dynamic-balance surface 62 facing away from the third dynamic-balance surface 61. Along an axis direction perpendicular to the second dynamic-balance component 6, a cross-sectional area of the fourth dynamic-balance surface 62 may be smaller or less than that of the third dynamic-balance surface 61.
[0047] Further, the third dynamic-balance surface 61 may comprise a groove with an axial depth. The encoder 4 may achieve dynamic balancing through components on the fourth dynamic-balance surface 62. In some cases, the second dynamic-balance component 6 may comprise a third sidewall extending away from the second bearing support 12 around the edge of the third dynamic-balance surface 61, a fourth sidewall extending toward the second bearing support 12 around the edge of the fourth dynamic-balance surface 62, and / or a second counterweight groove 63 formed by the fourth dynamic-balance surface 62, an outer wall of the third sidewall, and an inner wall of the fourth sidewall. The second counterweight groove 63 may accommodate a plurality of second counterweight elements to achieve dynamic balancing of the encoder 4 rotation speeds of e.g., at least about 300 rpm. In some cases, the encoder 4 does not directly contact the second dynamic-balance component 6. In some instances, the material of the second counterweight groove 63 can be magneto-electric material. In some cases, the material of the second counterweight element (s) can be a magneto-electric material.
[0048] Referring to FIG. 2, an exemplary schematic structural diagram of a LiDAR system is illustrated. The LiDAR system 100 provided may comprise an optical component, e.g., the polygonal mirror 3 and the rotating device 10. In some cases, the rotating device 10 may be configured to enable the LiDAR system 100 to emit light beams externally through the polygonal mirror 3.
[0049] In some embodiments, the rotating device may be coupled to the polygonal mirror and the motor rotor through a plurality of connecting elements, described elsewhere herein, which can reduce vibration and noise when the polygonal mirror rotates around the bearing. Moreover, by connecting or coupling the bearing to the bearing support and the motor, concentricity between the motor and the polygonal mirror when the motor driving is maintained. Additionally, in some cases, brackets capable of accommodating counter counterweight elements may be respectively sleeved between two bearing supports, described elsewhere herein, and outside the bearing support to reduce the centrifugal force of the polygonal mirror and the rotating device thereof. LiDAR Optical Engine Calibration Methods, Devices, and Systems
[0050] In some embodiments, as described herein, a LiDAR optical engine may comprise multiple channels B (for example, as shown in FIG. 10) , each arranged at a desired installation angle. One or more channels may be disposed on one or more emitter boards. Different channels may correspond to different desired installation angles of the channel. In some embodiments, the multiple channels may be spaced apart from one another with a first spacing an a second spacing, as illustrated, for example, in FIG. 10. In some embodiments, the multiple channels may be spaced apart from one another with a first spacing in a first region of on a substrate (e.g., circuit board) that differs from a second spacing in a second region of the board that does not overlap with the first region of the board, as shown in FIG. 10.
[0051] In some embodiments, a channel may comprise a detection loop formed by a laser emitter, a laser receiver, and one or more optical components. Due to errors in large scale manufacturing processes and production techniques, the actual installation angle of each channel may deviate from the desired installation angle, resulting in deviations between the obtained LiDAR point cloud results and the actual LiDAR point cloud results of an environment being surveyed.
[0052] To better restore the actual LiDAR point cloud results, the disclosure, in some embodiments, provides a calibration method for one or more LiDAR optical engine channel angle errors. By leveraging the calibration methods, devices, and systems, described elsewhere herein, one may calibrate each channel of a plurality of channels of a LiDAR optical engine to improve an accuracy of the LiDAR system in mapping the environment surround or adjacent to the LiDAR system to the point cloud produced by the LiDAR system. In some
[0053] Referring again to FIGs. 6-7, the disclosure further provides a calibration device 100 for angle errors of LiDAR channels. The calibration device 100 may arranged opposite to a calibration target 200 and comprises a LiDAR optical engine 7, a moveable component 2, a fixed frame 4, and a controller 8. The LiDAR optical engine 7 may comprise multiple channels. The moveable component 2 may be configured to drive the LiDAR optical engine 7 to tilt vertically and / or rotate horizontally relative to the calibration target 200. The controller 8 may be electrically connected to the LiDAR optical engine 7, the moveable component 2, and an image acquisition device 300. The controller 8 may be configured to control the LiDAR optical engine 7 to select and illuminate channels, to control the moveable component 2 to move and thereby drive the LiDAR optical engine 7 to move relative to the calibration target 200, and to control the image acquisition device 300 to acquire a calibration target image of the channel to be calibrated and to calculate and analyze the calibration target image to obtain the center offset angle of the channel to be calibrated. In some embodiments, the structure and relationship between the calibration device 100 and the calibration target 200 may assist to ensure that after the LiDAR optical engine 7 is fixed to the fixed frame 4, the detection center of the LiDAR optical engine 7 is aligned with the center of the calibration target. In some cases, the LiDAR optical engine 7 may be aligned with the center of the calibration target 200 by using measurement equipment to calculate the relative position between the LiDAR optical engine and the calibration target to determine whether the LiDAR optical engine and the calibration target a properly aligned. In some cases, the LiDAR optical engine 7 may be aligned with the center of the calibration target 200 by utilizing a tooling structure that may maintain a constant relative position between the LiDAR optical engine 7 and the calibration target 200. In some cases, the tooling structure may allow for the use of the calibration systems, devices, and methods, described elsewhere herein, with LiDAR optical engines of e.g., varying size and optical configured may be calibrated using a single devices, systems, and methods.
[0054] Referring again to FIG. 7, the disclosure further provides a calibration system 1000 for angle errors of LiDAR channels, including a calibration device 100, a calibration target 200, and an image acquisition device 300. The image acquisition device 300 may be independently arranged relative to the calibration target 200 and the calibration device 100 facing the calibration target 200. The shooting range of the image acquisition device 300 may cover an en-face perspective of the calibration target 200 when the image acquisition device is positioned nearby to the calibration device 100. In some cases, the image acquisition device 300 may be placed at angle with respect to the optical axis of the one or more channels of the LiDAR optical engine 7 this is being calibrated, as shown in FIG. 7. The angle of the image acquisition device 300 may prevent from the image acquisition device 300 to obstruct the path of light emitting by the channel towards the calibration target 200. The image acquisition device 300 may be electrically connected to the controller 8. In some cases, the image acquisition device 300 may comprise a camera, and the controller 8 may control the camera to acquire an image of the current calibration target 200 in the form of an image or photograph. In some embodiments, the image acquisition device 300 may be wirelessly connected to the controller 8. In some cases, the image acquisition device 300 may be wired to the controller 8. In some cases, the sizes of the calibration target 200 and the calibration device 100, as well as the driving mode of the calibration device 100 and the LiDAR optical engine 7, can be set according to actual needs and are not limited herein.
[0055] Referring to FIGs. 3 and 4-5, FIG. 3 shows an exemplary flowchart of the calibration method for LiDAR channel angle errors. FIG. 6 shows an exemplary schematic diagram of the electrical connections of the calibration device for LiDAR channel angle errors. FIG. 7 shows an exemplary schematic diagram of the structure of the calibration system for LiDAR channel angle errors.
[0056] In some cases, the calibration method for LiDAR channel angle errors provided by the disclosure may applied to a calibration device 100, which faces a calibration target 200, as shown in FIG. 7. In some cases, the calibration device 100 may comprise a LiDAR system. In some cases, a calibration device 100 for calibrating channel angular errors for a LiDAR optical engine may comprise: a movable component 2 configured to drive the LiDAR optical engine 7 to deflect relative to a calibration target 200 in one or more directions; and a controller operably coupled to the movable component, where the controller comprises a memory, configured to store computer programs and a processor, configured to execute the computer programs to perform a calibration method comprising: controlling the movable component to move to align a detection center of the LiDAR optical engine with a center of the calibration target, selecting a channel from a plurality of the channels in the LiDAR optical engine to be calibrated and activating an emitter of the selected channel to project a real light spot, controlling the movable component to move at a deflection angle in the one or more directions to align the selected channel with the center of the calibration target by aligning the real light spot with the center of the calibration target, and determining an offset angle for the selected channel based at least in part on the deflection angle, and calibrating the selected channel based on the offset angle. In some cases, the detection center of the LiDAR optical engine may be a center of a detection area of the plurality of channels. In some cases, the LiDAR optical engine 7 may be coupled to a fixed mounting base 9. In some embodiments, the fixed mounting base 9 may maintain a spatial relationship between the LiDAR optical engine 7 and the movable component 2. In some cases, the center of the calibration target may be represented by a reference marker on the calibration target. In some embodiments, the one or more directions may comprise a horizontal direction and a vertical direction. In some cases, the deflection angle in the one or more directions comprises a horizontal deflection angle or a vertical deflection angle. In some embodiments, the calibration method may further comprise selecting a next channel from the plurality of channels and repeating (c) and (d) . In some cases, the offset angle may be stored in a lookup table for calibrating the selected channel. In some instances, the deflection angle may be based on a command generated by the controller.
[0057] In some cases, a calibration device 100 for calibrating channel angular errors for a LiDAR optical engine may comprise: a movable component 2 configured to drive the LiDAR optical engine 7 to deflect relative to a calibration target 200 in one or more directions; and a controller operably coupled to the movable component, where the controller comprises a memory, configured to store computer programs and a processor, configured to execute the computer programs to perform a calibration method comprising: controlling the movable component to move to align a detection center of the LiDAR optical engine with a center of the calibration target, selecting one or more channels from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of each of the selected one or more channels to project a real light spot to the calibration target, acquiring an image of the calibration target containing one or more of the real light spots, with an imaging acquisition device, and determining an offset angle for each of the selected one or more channels based at least in part on an offset position between a real light spot and a respective reference spot in the acquired image. In some cases, the one or more channels may be activated simultaneously, and where the acquired image contains one or more of the real light spots emitted simultaneously. In some cases, the one or more channels may be activated sequentially, where the acquired image is an image containing a real light spot emitted from a single channel, and where one or more of the images are superimposed to generate a superimposed image. In some cases, the superimposed image may be analyzed to determine the offset angle of each of the selected one or more channels. In some instances, the offset position may comprise an offset of the real light spot relative to the respective reference spot measured in the acquired image in a horizontal direction or in a vertical direction. In some cases, the offset angle may be determined based at least in part on the offset position and a known spatial relationship between the calibration target, the LiDAR optical engine, and the image acquisition device. In some cases, the one or more directions may comprise a horizontal direction and a vertical direction. In some cases, the offset angle may be stored in a lookup table for calibrating the selected channel.
[0058] The calibration device 100 may be configured to calibrate each channel of a LiDAR optical engine 7. The calibration device 100 may comprise a controller or one or more processors 8, and a moveable component 2, as shown in an example configuration in FIG. 6. The LiDAR optical engine 7 may be installed on the moveable component 2, and both the LiDAR optical engine 7 and the moveable component 2 may be electrically connected to the controller 8. The controller 8 may be configured to control the moveable component 2 to deflect in multiple directions such as the vertical direction (s) and / or the horizontal direction (s) to drive the LiDAR optical engine 7 to deflect relative to the calibration target 200.
[0059] It is understood that due to manufacturing production deviations and tolerances, there may an offset between the actual installation angle of one or more channels of a plurality of channels of a LiDAR optical engine and the desired installation angle of each channel. By obtaining the offset between the actual installation angle and the desired installation angle of each channel through a calibration method, as described elsewhere herein, each channel can be calibrated, thereby improving the accuracy of the detection results of the LiDAR optical engine 1. Provided herein are calibration methods for determining the offset between each channel's actual and desired installation angles. In some embodiments, the calibration method may comprise: controlling the deflection of the moveable component 2 to successively align each channel to be calibrated with the center of a calibration target, and deriving an offset between the actual installation angle and the desired installation angle of each channel to be calibrated based on the deflection amount of the moveable component 2. In some embodiments, the calibration method may comprise obtaining a calibration target image including real spots and reference spots corresponding to the actual installation angle and the desired installation angle and obtaining the offset between the actual installation angle of a channel and the desired installation angle of the channel through image calculation and analysis, described elsewhere herein. Although a single channel can be aligned with the center of the calibration target at a given time, a calibration target image containing spots corresponding to a plurality of channels can be obtained simultaneously. In some cases, the calibration method can operate on one channel. In some instances, the calibration method can operate on multiple channels simultaneously.
[0060] In some embodiments, the disclosure provides a calibration method for LiDAR channel angle errors, for example, steps S10 to S60 as shown in FIG. 3. In some cases, the method of calibrating angular errors for a LiDAR optical engine, may comprise: (a) controlling a moveable component to move in one or more directions to align a detection center of the LiDAR optical engine with a center of a calibration target; (b) selecting a channel from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of the selected channel to project a real light spot; (c) controlling the movable component to move at a deflection angle in the one or more directions to align the selected channel with the center of the calibration target by aligning the real light spot with the center of the calibration target; and (d) determining an offset angle for the selected channel based at least in part on the deflection angle, and calibrating the selected channel based on the offset angle. In some cases, the method of calibrating angular errors for a LiDAR optical engine, may comprise: controlling a movable component to move in one or more directions to align a detection center of the LiDAR optical engine with a center of the calibration target; selecting one or more channels from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of each of the selected one or more channels to project a real light spot to the calibration target; acquiring an image of the calibration target containing one or more of the real light spots with an imaging acquisition device; and determining an offset angle for each of the selected one or more channels based at least in part on an offset position between a real light spot and a respective reference spot in the acquired image.
[0061] In some embodiments, the calibration method may comprise step S10: controlling the moveable component 2 to move to align a detection center of the LiDAR optical engine 7 with a center of the calibration target. In some case, the controller 8 may control the moveable component 2 to move such that the detection center of the LiDAR optical engine 7 is aligned with the center of the calibration target. In some cases, the detection center may comprise a center of the detection area formed by all channels. The term “detection center” as used herein refers to a virtual reference point associated with a LiDAR sensor, and more specifically a multi-channel LiDAR, from which all emitted laser beams are considered to originate and to which all received reflections are referenced. In some cases, a multi-channel LiDAR includes a plurality of discrete laser transmitters and detectors, each having a slightly different physical emission origin. Without calibration, the point cloud data generated by such a device may include inter-channel offsets, resulting in misalignment and geometric distortion. By defining a common detection center, the outputs of all channels may be unified into a single sensor coordinate system, thereby enabling consistent three-dimensional reconstruction. In some cases, the detection center may not necessarily coincide with any single physical laser emitter but is instead a virtual geometric center computed during the calibration process.
[0062] In one example, the detection center may be defined as the intersection point of the optical axes of the plurality of channels, or as the point that minimizes the aggregate positional error between the measured returns and known reference positions. For each channel, an initial estimate of the emission origin is determined by aligning the measured point cloud data with the known geometry of the reference targets. This may involve identifying systematic offsets or angular deviations between the measured and actual target locations. Once the emission origins of the respective channels are determined, the method computes the relative offsets among the channels. A virtual detection center is then calculated. In one example, the detection center is defined as a point that minimizes the sum of squared distances from the virtual point to the estimated emission origins of the channels. In another example, the detection center is iteratively refined by transforming the point cloud data into a common coordinate frame, aligning the transformed point cloud with the known reference targets, and updating the virtual reference point until the residual error falls below a predetermined threshold.
[0063] In some embodiments, the method may comprise step S20: selecting one or more channels to be calibrated. In some cases, the controller 8 may control the LiDAR optical engine 7 to select one or more channels of a plurality of channels of a LiDAR optical engine to be calibrated.
[0064] In some embodiments, the calibration method may comprise step S30: according to an orientation between the LiDAR optical engine 7 and the calibration target 200, controlling the channels to be calibrated to project onto the calibration target 200 in a predetermined direction to obtain one or more corresponding spot centers. The orientation may comprise aligning each channel to be calibrated with the center of the calibration target or the detection center of the LiDAR optical engine 7 aligned with the center of the calibration target. In some embodiments, the controller 8 may control the movement of the moveable component 2 to enable each channel of the LiDAR optical engine to be calibrated to be successively aligned with the center of the calibration target. In some cases, once a channel is aligned, the controller 8 may activate or illuminate the currently aligned channel to be calibrated once. In some cases, according to the desired installation angle of the channel to be calibrated, the controller 8 may move the moveable component 2 such that the channel to be calibrated is aligned with the center at zero-degree pitch and zero-degree yaw ( [0, 0] ) of the calibration target.
[0065] In some cases, the center of the calibration for a given channel may be greater or less than zero-degree pitch and zero-degree yaw of the calibration target. For example, the desired installation angle corresponding to the channel to be calibrated is [θpitch, θyaw] , which means moving the moveable component 2 by [-θpitch, -θyaw] to align the channel with the center of the calibration target. Since the desired installation angle represents the ideal setting for the channel, not the actual installation angle of a given channel, therefore, when the moveable component 2 is moved according to the desired installation angle, the channel to be calibrated is theoretically aligned with the center [0, 0] of the calibration target, but when conducted in practice, the spot projected by the channel to be calibrated does not align with the center [0, 0] of the calibration target. For example, assume that the desired installation angle of a channel to be calibrated is [2, 2] , and the actual installation angle of the channel to be calibrated is [3, 3] , according to the desired installation angle [2, 2] , the moveable component 2 may be adjusted by an angle of [-2, -2] , however the channel to be calibrated will align with an angle of [1, 1] instead of the center [0, 0] of the calibration target.
[0066] In some embodiments, when the orientation comprises aligning the detection center of the LiDAR optical engine 7 with the center of the calibration target 200, the calibration method may comprise step S30: the controller 8 successively or simultaneously activates or illuminates one or more channels of the LiDAR optical engine to be calibrated.
[0067] In some embodiments, the calibration method may comprise step S40: acquiring an image of the calibration target 200 to obtain the real spot and the reference spot of the channels to be calibrated. In some embodiments, the real spot may be the spot projected by the channel to be calibrated onto the calibration target 200. In some cases, the reference spot may be predetermined within the calibration target 200. In some cases, the reference spot (s) may be visible with an infrared camera or detector. When each channel to be calibrated is in an orientation where it is aligned with the center of the calibration target, the reference spot may correspond to the center of the calibration target; when the detection center of the LiDAR optical engine 7 is aligned with the center of the calibration target, the reference spot may have a one-to-one correspondence with the center of the channel to be calibrated. The image may be captured through an image acquisition device 300. Specifically, the controller 8 controls the image acquisition device 300 to capture the current image of the calibration target 200. In some cases, the controller 8 may obtain the current image of the calibration target 200 from the image acquisition device 300 and derive, distinguish, or identify the real spot and the reference spot of the current channel to be calibrated based on the current image of the calibration target 200.
[0068] Referring to FIG. 8, an exemplary calibration target image is shown. In some cases, when the orientation is such that each channel to be calibrated is aligned with the center of the calibration target A, the image of the calibration target may be captured to obtain the actual light spot B and reference light spot of the channel to be calibrated. In some cases, the position of the reference light spot may correspond to the center of the calibration target A. It is understandable that the orientation between the actual light spot B and the center of the calibration target A can be either coinciding or offset, as disused elsewhere herein.
[0069] Referring to FIG. 9, an exemplary calibration target image is shown. In some embodiments, when the orientation is such that the detection center of the LiDAR optical engine 7 is aligned with the center of the calibration target, the controller 8 may sequentially control multiple channels to project onto the calibration target 200 in a predetermined direction to obtain individual calibration target images for each channel. The controller 8 may use software image superimposition to overlay a plurality of individual calibration target images, and as a result, a superimposed calibration target image of multiple channels as shown in FIG. 9, may be generated, produced, or obtained. In some cases, the controller 8 may simultaneously control multiple channels to project light beams onto the calibration target 200 in a predetermined direction. The imaging device may capture an image containing a plurality of the actual light spots B and reference light spots A corresponding to the multiple channels. A superimposed calibration target image of multiple channels may be generated at once, thereby obtaining the actual light spots B and reference light spots A of multiple channels through the superimposed calibration target image, as shown in FIG. 9. As described above, the plurality of reference light spots A may be markers that are visible with an infrared camera or detector that can detect both the real / actual light spots and the reference light spots. In some embodiments, the reference light spot corresponds to the light spot associated with the desired installation angle of the channel to be calibrated.
[0070] In some embodiments, the method may comprise step S50: determining a vertical offset angle and a horizontal offset angle of the channel to be calibrated based on the orientation between the obtained actual light spot and reference light spot of the channel to be calibrated. In some embodiments, the controller 8 may obtain the orientation between the actual light spot and reference light spot from the current image of the calibration target 200 and determine the vertical offset angle and horizontal offset angle of the channel to be calibrated based on this orientation.
[0071] Referring to FIG. 4, an exemplary sub-flowchart of the calibration method for LiDAR channel angle error in accordance with a first embodiment is illustrated. In some embodiments, when the orientation is such that each channel to be calibrated is aligned with the center of the calibration target, the calibration method may comprise steps S501-S502.
[0072] In some embodiments, the calibration may comprise step S501: according to an orientation between the real spots of the channels to be calibrated and the center of the calibration target, controlling the moveable component 2 to deflect in the vertical direction and / or horizontal direction until the actual light spot coincides with the center of the calibration target. In some cases, the controller 8 may determine the orientation between the actual light spot and the center of the calibration target based on image information. If the orientation indicates that the actual light spot has deviated from the center of the calibration target, the controller 8 may control the moveable component 2 to deflect in the vertical direction so that the actual light spot and the center of the calibration target are on the same horizontal line. Subsequently, the controller 8 may control the moveable component 2 to deflect in the horizontal direction so that the actual light spot fully coincides with the center of the calibration target. In some cases, if the orientation indicates that the actual light spot coincides with the center of the calibration target, such orientation may indicate that the actual installation angle of the selected channel matches the desired installation angle and thus there is no need to move the moveable component 2. In some cases, when there is no need to move the moveable component 2, the offset angle of the selected channel is directly recorded as zero-degrees pitch and zero-degrees yaw ( [0, 0] ) .
[0073] In some cases, the calibration method may comprise step S502: determining the vertical offset angle and horizontal offset angle of the channel to be calibrated based on the deflection angles of the moveable component 2 in the vertical and horizontal directions. In some instances, the controller 8 may obtain the deflection angles of the moveable component 2 in the vertical and horizontal directions, which correspond to the vertical offset angle and horizontal offset angle of the channel to be calibrated.
[0074] Referring to FIG. 5, an exemplary sub-flowchart of the calibration method for LiDAR channel angle error in accordance. In some embodiments, when the orientation is such that the detection center of the LiDAR optical engine 7 is aligned with the center of the calibration target, the calibration method may comprise steps S503-S505.
[0075] In some embodiments, the calibration method may comprise step S503: measuring a first vertical offset length and a first horizontal offset length of the actual light spot relative to the reference light spot of each channel to be calibrated in the image. In some embodiments, the first vertical offset length and the first horizontal offset length of the actual light spot relative to the reference light spot of each channel to be calibrated may be determined from a measured distance between the centroid of the actual light spot and a centroid of the reference light spot. In some embodiments, the controller 8 may measure the first horizontal offset length and first vertical offset length of the actual light spot relative to the reference light spot for each channel based on the image. In some embodiments, the first horizontal offset length and first vertical offset length may be measured or recorded in pixel units.
[0076] In some embodiments, the calibration method may comprise step S504: converting the first horizontal offset length and the first vertical offset length into a second horizontal offset length and a second vertical offset length in the spatial domain, representing the actual position of the real spot relative to the reference spot. In some embodiments, the second horizontal offset length and the second vertical offset length may be measured and recorded in spatial length units, e.g., micrometers, millimeters, centimeters, etc. In some embodiments, the process 32 of the controller 8 may convert the offset length of the real spot relative to the reference spot from pixel units to spatial length. In some cases, a method of converting the offset length of the real spot relative to the reference spot may comprise referencing a physical scale on the calibration target panel and using the scale as a reference to the offset processing or calculation of physical distance of offset. In some embodiments, a method of converting the offset length of the real spot relative to the reference spot may comprise calculating the specific size of a single pixel projected onto the calibration target 200 to determine the spatial length of the offset geometrically.
[0077] In some embodiments, the calibration method may comprise step S505: determining the vertical offset angle and the horizontal offset angle of the channel to be calibrated based on the second horizontal offset length and the second vertical offset length. In some embodiments, the horizontal offset angle offsetyaw and the vertical offset angle offsetpitch for each channel may be determined by combining the second horizontal offset length and the second vertical offset length with the spatial distance between the LiDAR optical engine 7 and the calibration target 200. The calculation methods for the horizontal offset angle offsetyaw and the vertical offset angle offsetpitchcan be as follows, for example, assume that the vertical offset length and the spatial distance between the LiDAR optical engine 7 and the calibration target 200 is N, and after measurement, the second horizontal offset length is obtained Lenyaw, and the vertical offset length is obtained as Lenpitch, then the second horizontal offset angle can be calculated as offsetyaw=arctan (Lenyaw / N) and the second vertical offset angle can be calculated as offsetpitch=arctan (Lenpitch / N) . In this example, the spatial distance N between the LiDAR optical engine 7 and the calibration target 200 can be configured based on the circumstances for a given measurement. Given that, different LiDAR optical engine designs should use different distances, and the spatial distance N between the LiDAR optical engine 7 and the calibration target 200 can be obtained in any way, such as directly through the laser ranging function of the LiDAR optical engine 7. The spatial distance N between the LiDAR optical engine 7 and the calibration target 200, and the calculation method for the spatial distance N are not limited herein.
[0078] In some embodiments, the calibration method may comprise step S60: calibrating the channels to be calibrated based on the vertical offset angles and the horizontal offset angles of the channels to be calibrated. In some cases, the controller 8 may determine the central offset angle [θpitch+offsetpitch, θyaw+offsetyaw] of the channel to be calibrated based on the vertical offset angle offsetpitchand horizontal offset angle offsetyawof the channel to be calibrated, described elsewhere herein, and then calibrates the channel based on the central offset angle. For example, assume that the desired installation angle of the channel to be calibrated is [2, 2] , and both the vertical offset angle and the horizontal offset angle of the actual installation angle of the channel relative to the desired installation angle are 1, then the central offset angle of the channel to be calibrated is [2+1, 2+1] , that is [3, 3] . In this example, the controller 8 would writes the central offset angle [θpitch+offsetpitch, θyaw+offsetyaw] into a calibration table. It is understandable that after applying the above calibration method to all channels, the calibration table records the central offset angles of all channels, with each channel corresponding to a unique central offset angle.
[0079] The calibration method for LiDAR channel angle errors, as described above, can be executed by: manipulating the moveable component 2 to ensure that the real spot precisely aligns with the center of the calibration target. In some embodiments, the calibration method may comprise utilizing the horizontal and vertical deflection angles of the moveable component 2, to derive the vertical and horizontal offset angles that represent the deviation of the actual installation angle of the channel to be calibrated from the desired installation angle. In some embodiments, the calibration method may comprise iteratively obtaining calibration target images of multiple channels and measuring the vertical offset length and the horizontal offset length from the calibration target images for multiple channels using a best first search algorithm. In some embodiments, the method may comprise measuring the vertical and horizontal offset lengths between the spots corresponding to the actual and desired installation angles of each channel. In some embodiments, the processor of the controller may integrate the measured lengths with the actual control distance between the LiDAR optical engine 7 and the calibration target 200, to determine or compute the vertical and horizontal offset angles for each channel’s actual installation angle relative to the desired installation angle. The calibration method provided herein significantly enhances the detection accuracy of the LiDAR optical engine 7 when reconstructing a surround or adjacent environment scanned with the LiDAR system from a point cloud representation.
[0080] In some cases, the disclosure provides a controller 8 including a memory 33 and a processor 34, as shown in FIG. 6. The memory 33 may be configured to store computer programs, and the processor 34 may be configured to execute the computer programs to implement a calibration method, described elsewhere herein, for angle errors of LiDAR channels. In some embodiments, the processor 34 may be a Central Processing Unit (CPU) 32, a microcontroller 8, a microprocessor 34, or other data processing chips for running mobile calibration program instructions stored in the memory 33.
[0081] The memory 33 may comprise at least one type of readable storage medium, e.g., flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory, etc. ) , magnetic storage, magnetic disks, optical disks, and the like. In some embodiments, the memory 33 may be an internal storage unit of a computer device, such as the hard disk of the computer device. In some embodiments, the memory 33 may also be a storage device of an external computer device, such as a plug-in hard disk equipped on a computer device, a Smart Media Card (SMC) , a Secure Digital (SD) card, or a Flash Card. In some embodiments, the memory 33 may comprise both an internal storage unit of a computer device and an external storage device. The memory 33 may be used to store application software and various data installed on the computer device, e.g., code for implementing mobile intelligent processing, or to store temporarily store data that has been output or will be output.
[0082] The above disclosed preferred embodiments of the invention are intended only to assist in the elaboration of the invention. The preferred embodiment does not elaborate on all the details and does not limit the invention to a specific embodiment. According to the contents of this instruction manual, a lot of amendments and changes can be made. These embodiments are selected and described in detail in this specification for the purpose of better explaining the principle and practical application of the invention, so that the technical personnel in the technical field can better understand and utilize the invention.
[0083] Any systems, methods, software, compositions, and platforms described herein are modular and not limited to sequential steps. Accordingly, terms such as “first” and “second” do not necessarily imply priority, order of importance, or order of acts.
[0084] The section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.
Claims
1.A rotating device for Light Detection and Ranging (LiDAR) system comprising:a motor configured to drive an optical component to have a rotary movement; anda bearing disposed between a first bearing support and a second bearing support, wherein the motor and the optical component are sleeved onto the bearing and wherein the motor is configured to drive the optical component via the bearing thereby reducing vibration and noise or centrifugal force.2.The rotating device of claim 1, wherein the first bearing support and the second bearing support are oppositely arranged with respect to each other.3.The rotating device of claim 2, wherein a stator of the motor is connected to a surface of the first bearing support facing toward the second bearing support.4.The rotating device of claim 1, wherein the motor comprises an outer rotor and wherein the outer rotor is located at an end surface of the motor facing away from the first bearing support.5.The rotating device of claim 4, wherein the optical component comprises a polygonal mirror comprising a first end surface, and a second end surface opposite to the first end surface.6.The rotating device of claim 5, wherein the first end surface is connected to the outer rotor through a plurality of connecting elements.7.The rotating device of claim 5, wherein an end of the bearing is connected to the second bearing support, and wherein another end of the bearing is configured to pass through the second end surface and the first end surface of the polygonal mirror and connected to the motor.8.The rotating device of claim 7, wherein the outer rotor and the polygonal mirror are respectively sleeved on the bearing.9.The rotating device of claim 1, wherein the first bearing support and the second bearing support is connected to a base.10.The rotating device of claim 9, wherein the first bearing support and the second bearing support are parallelly arranged, and respectively connected to a same end surface of the base.11.The rotating device of claim 10, wherein the polygonal mirror and the outer rotor respectively have a gap with the base.12.The rotating device of claim 4, wherein an end surface of the outer rotor is connected to a motor base facing toward the first bearing support, and wherein the motor base is connected to the first bearing support.13.The rotating device of claim 1, wherein the optical component comprises a polygonal mirror formed by a plurality of mirrors surrounding edges of a first end surface and a second end surface of the optical component, wherein each mirror is connected to an adjacent mirror, and parallel to the bearing.14.The rotating device of claim 1, wherein the plurality of connecting elements is symmetrically arranged around the bearing.15.The rotating device of claim 1, wherein the optical component is configured to direct light beams emitted by the LiDAR.16.The rotating device of claim 1, wherein the rotating device further comprises an encoder located on a surface of the second bearing support facing away from the first bearing support, wherein the encoder is configured to measure positions or rotating speed of the motor which are used to generate control instructions for directing light beams.17.The rotating device of claim 16, wherein the control instructions are transmitted to the motor to adjust operating data of the motor.18.The rotating device of claim 17, wherein the operating data comprises rotational speed data representing a rotational speed of the motor, and position data representing a rotational position of the motor.19.The rotating device of claim 1, further comprising a first dynamic-balance component, wherein the first dynamic-balance component comprises a first dynamic-balance surface facing toward the first bearing support, and a second dynamic-balance surface facing away from the first dynamic-balance surface.20.The rotating device of claim 19, wherein the first dynamic-balance surface is in direct contact with an end surface of a rotor of the motor facing toward the second bearing support.21.The rotating device of claim 20, wherein along an axis direction perpendicular to the first dynamic-balance component, a cross-sectional area of the first dynamic-balance surface is smaller than a cross-sectional area of the second dynamic-balance surface.22.The rotating device of claim 21, wherein the first dynamic-balance component further comprises a first sidewall extending toward the second bearing support around an edge of the first dynamic-balance surface, a second sidewall extending toward the first bearing support around an edge of the second dynamic-balance surface, and a first counterweight groove formed by the second dynamic-balance surface, an outer wall of the first sidewall, and an inner wall of the second sidewall, wherein the first counterweight groove accommodates a plurality of first counterweight elements.23.The rotating device of claim 22, wherein the rotating device further comprises a second dynamic-balance component located on a surface of the second bearing support facing away from the optical component and wherein the second dynamic-balance component has a gap with the second bearing support.24.The rotating device of claim 23, wherein the second dynamic-balance component is provided with a third dynamic-balance surface facing toward the second bearing support and a fourth dynamic-balance surface facing away from the third dynamic-balance surface.25.The rotating device of claim 24, wherein along an axis direction perpendicular to the second dynamic-balance component, a cross-sectional area of the fourth dynamic-balance surface is smaller than a cross-sectional area of the third dynamic-balance surface.26.The rotating device of claim 25, wherein the second dynamic-balance component further comprises a third sidewall extending away from the second bearing support around the edge of the third dynamic-balance surface, a fourth sidewall extending toward the second bearing support around the edge of the fourth dynamic-balance surface, and a second counterweight groove formed by the fourth dynamic-balance surface, an outer wall of the third sidewall, and an inner wall of the fourth sidewall, wherein the second counterweight groove accommodates a plurality of second counterweight elements.27.The rotating device of claim 1, wherein the rotary movement is at a speed of at least 300 rpm.28.A Light Detection and Ranging (LiDAR) system comprising:an optical component; anda rotating device configured to drive the optical component to have a rotary movement, wherein the rotating device comprises:a bearing disposed between a first bearing support and a second bearing support, anda motor configured to drive the optical component via the bearing thereby reducing vibration and noise or centrifugal force, wherein the motor and the optical component are sleeved onto the bearing.29.The LiDAR of claim 28, wherein the first bearing support and the second bearing support are oppositely arranged with respect to each other.30.The LiDAR of claim 29, wherein a stator of the motor is connected to a surface of the first bearing support facing toward the second bearing support.31.The LiDAR of claim 28, wherein the motor comprises an outer rotor and wherein the outer rotor is located at an end surface of the motor facing away from the first bearing support.32.The LiDAR of claim 31, wherein the optical component comprises a polygonal mirror comprising a first end surface, and a second end surface opposite to the first end surface.33.The LiDAR of claim 32, wherein the first end surface is connected to the outer rotor through a plurality of connecting elements.34.The LiDAR of claim 32, wherein an end of the bearing is connected to the second bearing support, and wherein another end of the bearing is configured to pass through the second end surface and the first end surface of the polygonal mirror and connected to the motor.35.The LiDAR of claim 34, wherein the outer rotor and the polygonal mirror are respectively sleeved on the bearing.36.The LiDAR of claim 28, wherein the first bearing support and the second bearing support is connected to a base.37.The LiDAR of claim 36, wherein the first bearing support and the second bearing support are parallelly arranged, and respectively connected to a same end surface of the base.38.The LiDAR of claim 37, wherein the polygonal mirror and the outer rotor respectively have a gap with the base.39.The LiDAR of claim 31, wherein an end surface of the outer rotor is connected to a motor base facing toward the first bearing support, and wherein the motor base is connected to the first bearing support.40.The LiDAR of claim 28, wherein the optical component comprises a polygonal mirror formed by a plurality of mirrors surrounding edges of a first end surface and a second end surface of the optical component, wherein each mirror is connected to an adjacent mirror, and parallel to the bearing.41.The LiDAR of claim 28, wherein the plurality of connecting elements is symmetrically arranged around the bearing.42.The LiDAR of claim 28, wherein the optical component is configured to direct light beams emitted by the LiDAR.43.The LiDAR of claim 28, wherein the rotating device further comprises an encoder located on a surface of the second bearing support facing away from the first bearing support, wherein the encoder is configured to measure positions or rotating speed of the motor which are used to generate control instructions for directing light beams.44.The LiDAR of claim 43, wherein the control instructions are transmitted to the motor to adjust operating data of the motor.45.The LiDAR of claim 44, wherein the operating data comprises rotational speed data representing a rotational speed of the motor, and position data representing a rotational position of the motor.46.The LiDAR of claim 28, further comprising a first dynamic-balance component, wherein the first dynamic-balance component comprises a first dynamic-balance surface facing toward the first bearing support, and a second dynamic-balance surface facing away from the first dynamic-balance surface.47.The LiDAR of claim 46, wherein the first dynamic-balance surface is in direct contact with an end surface of a rotor of the motor facing toward the second bearing support.48.The LiDAR of claim 47, wherein along an axis direction perpendicular to the first dynamic-balance component, a cross-sectional area of the first dynamic-balance surface is smaller than a cross-sectional area of the second dynamic-balance surface.49.The LiDAR of claim 48, wherein the first dynamic-balance component further comprises a first sidewall extending toward the second bearing support around an edge of the first dynamic-balance surface, a second sidewall extending toward the first bearing support around an edge of the second dynamic-balance surface, and a first counterweight groove formed by the second dynamic-balance surface, an outer wall of the first sidewall, and an inner wall of the second sidewall, wherein the first counterweight groove accommodates a plurality of first counterweight elements.50.The LiDAR of claim 49, wherein the rotating device further comprises a second dynamic-balance component located on a surface of the second bearing support facing away from the optical component and wherein the second dynamic-balance component has a gap with the second bearing support.51.The LiDAR of claim 50, wherein the second dynamic-balance component is provided with a third dynamic-balance surface facing toward the second bearing support and a fourth dynamic-balance surface facing away from the third dynamic-balance surface.52.The LiDAR of claim 51, wherein along an axis direction perpendicular to the second dynamic-balance component, a cross-sectional area of the fourth dynamic-balance surface is smaller than a cross-sectional area of the third dynamic-balance surface.53.The LiDAR of claim 52, wherein the second dynamic-balance component further comprises a third sidewall extending away from the second bearing support around the edge of the third dynamic-balance surface, a fourth sidewall extending toward the second bearing support around the edge of the fourth dynamic-balance surface, and a second counterweight groove formed by the fourth dynamic-balance surface, an outer wall of the third sidewall, and an inner wall of the fourth sidewall, wherein the second counterweight groove accommodates a plurality of second counterweight elements.54.The LiDAR of claim 28, wherein the rotary movement is at a speed of at least 300 rpm.55.A calibration device for calibrating channel angular errors for a LiDAR optical engine comprising:a movable component configured to drive the LiDAR optical engine to deflect relative to a calibration target in one or more directions; anda controller operably coupled to the movable component, wherein the controller comprises a memory, configured to store computer programs and a processor, configured to execute the computer programs to perform a calibration method comprising:(a) controlling the movable component to move to align a detection center of the LiDAR optical engine with a center of the calibration target,(b) selecting a channel from a plurality of the channels in the LiDAR optical engine to be calibrated and activating an emitter of the selected channel to project a real light spot,(c) controlling the movable component to move at a deflection angle in the one or more directions to align the selected channel with the center of the calibration target by aligning the real light spot with the center of the calibration target, and(d) determining an offset angle for the selected channel based at least in part on the deflection angle, and calibrating the selected channel based on the offset angle.56.The calibration device of claim 55, wherein the detection center of the LiDAR optical engine is a center of a detection area of the plurality of the channels.57.The calibration device of claim 55, wherein the center of the calibration target is represented by a reference marker on the calibration target.58.The calibration device of claim 55, wherein the one or more directions comprise a horizontal direction and a vertical direction.59.The calibration device of claim 55, wherein the deflection angle in the one or more directions comprise a horizontal deflection angle or a vertical deflection angle.60.The calibration device of claim 55, wherein the calibration method further comprises selecting a next channel from the plurality of channels and repeating (c) and (d) .61.The calibration device of claim 55, wherein the offset angle is stored in a lookup table for calibrating the selected channel.62.The calibration device of claim 55, wherein the deflection angle is based on a command generated by the controller.63.A calibration device for calibrating channel angular errors for a LiDAR optical engine comprising:a movable component configured to drive the LiDAR optical engine to deflect relative to a calibration target in one or more directions; anda controller operably coupled to the movable component, wherein the controller comprises a memory, configured to store computer programs and a processor, configured to execute the computer programs to perform a calibration method comprising:controlling the movable component to move to align a detection center of the LiDAR optical engine with a center of the calibration target,selecting one or more channels from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of each of the selected one or more channels to project a real light spot to the calibration target,acquiring an image of the calibration target containing one or more of the real light spots, with an imaging acquisition device, anddetermining an offset angle for each of the selected one or more channels based at least in part on an offset position between a real light spot and a respective reference spot in the acquired image.64.The calibration device of claim 63, wherein the one or more channels are activated simultaneously, and wherein the acquired image contains one or more of the real light spots emitted simultaneously.65.The calibration device of claim 63, wherein the one or more channels are activated sequentially, wherein the acquired image is an image containing a real light spot emitted from a single channel, and wherein one or more of the images are superimposed to generate a superimposed image.66.The calibration device of claim 65, wherein the superimposed image is analyzed to determine the offset angle of each of the selected one or more channels.67.The calibration device of claim 63, wherein the offset position comprises an offset of the real light spot relative to the respective reference spot measured in the acquired image a horizontal direction or a vertical direction.68.The calibration device of claim 63, wherein the offset angle is determined based at least in part on the offset position and a known spatial relationship between the calibration target, the LiDAR optical engine, and the image acquisition device.69.The calibration device of claim 63, wherein the one or more directions comprise a horizontal direction and a vertical direction.70.The calibration device of claim 63, wherein the offset angle is stored in a lookup table for calibrating the selected channel.71.A method of calibrating channel angular errors for a LiDAR optical engine, comprising:(a) controlling a moveable component to move in one or more directions to align a detection center of the LiDAR optical engine with a center of a calibration target;(b) selecting a channel from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of the selected channel to project a real light spot;(c) controlling the movable component to move at a deflection angle in the one or more directions to align the selected channel with the center of the calibration target by aligning the real light spot with the center of the calibration target; and(d) determining an offset angle for the selected channel based at least in part on the deflection angle, and calibrating the selected channel based on the offset angle.72.The calibration method of claim 71, wherein the detection center of the LiDAR optical engine is a center of a detection area of the plurality of the channels.73.The calibration method of claim 71, wherein the center of the calibration target is represented by a reference marker on the calibration target.74.The calibration method of claim 71, wherein the one or more directions comprise a horizontal direction or a vertical direction.75.The calibration method of claim 71, wherein the deflection angle in the one or more directions comprise a horizontal deflection angle or a vertical deflection angle.76.The calibration method of claim 71, wherein the calibration method further comprises selecting a next channel from the plurality of channels and repeating (c) and (d) .77.The calibration method of claim 71, wherein the offset angle is stored in a lookup table for calibrating the selected channel.78.The calibration method of claim 71, wherein the deflection angle is based on a command generated by the controller.79.A method of calibrating channel angular errors for a LiDAR optical engine, comprising:controlling a movable component to move in one or more directions to align a detection center of the LiDAR optical engine with a center of the calibration target;selecting one or more channels from a plurality of channels in the LiDAR optical engine to be calibrated and activating an emitter of each of the selected one or more channels to project a real light spot to the calibration target;acquiring an image of the calibration target containing one or more of the real light spots with an imaging acquisition device; anddetermining an offset angle for each of the selected one or more channels based at least in part on an offset position between a real light spot and a respective reference spot in the acquired image.80.The calibration method of claim 79, wherein the one or more channels are activated simultaneously, and wherein the acquired image contains one or more of the real light spots emitted simultaneously.81.The calibration method of claim 79, wherein the one or more channels are activated sequentially, wherein the acquired image is an image containing a real light spot emitted from a single channel, and wherein one or more of the images are superimposed to generate a superimposed image.82.The calibration method of claim 81, wherein the superimposed image is analyzed to determine the offset angle of each of the selected one or more channels.83.The calibration method of claim 81, wherein the offset position comprises an offset of the real light spot relative to the respective reference spot measured in the acquired image in a horizontal direction or in a vertical direction.84.The calibration method of claim 81, wherein the offset angle is determined based at least in part on the offset position and a known spatial relationship between the calibration target, the LiDAR optical engine, and the image acquisition device.85.The calibration method of claim 81, wherein the one or more directions comprise a horizontal direction and a vertical direction.86.The calibration method of claim 81, wherein the offset angle is stored in a lookup table for calibrating the selected channel.
Citation Information
Patent Citations
Angle calibration device and angle calibration method
CN113495257A
Laser radar outer rotor motor with rotating speed monitoring function and laser radar
CN114039460A
Rotating mirror structure and laser radar with same
CN115267731A
Laser radar calibration parameter determination method and device, storage medium and electronic equipment
CN115840216A
Laser radar angle calibration method and device, and storage medium
CN116482659A