Laser radar and scanning method
By forming and stitching a local vertical field of view in the lidar, the problems of large equipment size and high cost are solved, and high line count point cloud data acquisition and low power consumption are achieved, reducing motion distortion.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUHAN WANJI INFORMATION TECH
- Filing Date
- 2024-11-06
- Publication Date
- 2026-05-08
AI Technical Summary
The existing multi-line lidar equipment suffers from large size and high cost, mainly due to the increased number of laser transceiver modules.
By forming a local vertical field of view and stitching multiple local fields of view together, the entire vertical field of view is finally formed. By using a combination of rotating mirrors and transceiver modules, the working time of the laser and the rotation of the rotating mirror are controlled, thereby reducing the number of lasers.
It achieves high-line-count point cloud data acquisition, reduces device power consumption, minimizes motion distortion, and optimizes point cloud stitching effects.
Smart Images
Figure CN121995346A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of lidar technology, and in particular to a lidar and its scanning method. Background Technology
[0002] LiDAR, or lidar, is a sensor used to perceive parameters of the surrounding environment and is known as the "eyes" of machines. It has wide applications in surveying, exploration, and autonomous driving. Multi-line lidar is a key product for constructing three-dimensional environmental parameters; the higher the number of lines, the larger the vertical scanning field of view, and the richer the point cloud data acquired.
[0003] Currently, one way to achieve multi-line lidar is to increase the number of laser transceiver modules, but too many transceiver modules will increase the size and cost of the lidar. Summary of the Invention
[0004] This application proposes a lidar and scanning method to solve the problems of large size and high cost of large field-of-view lidar. It first forms a local vertical field of view, then forms multiple local vertical fields of view in sequence, and finally stitches them together to form the entire vertical field of view.
[0005] In a first aspect, embodiments of this application propose a scanning method for a laser, the apparatus comprising a rotating mirror and a transceiver module; the transceiver module comprising N groups of transmitting units arranged in a vertical direction, each group of transmitting units comprising M transmitting devices arranged in a horizontal direction; the rotating mirror comprising a rotation axis in a vertical direction and an L-shaped reflector rotating around the rotation axis; the method comprising:
[0006] The N sets of emitting units are driven to emit light, and the rotating mirror is driven to rotate.
[0007] When the nth group of emitting units emits light (n = 1 to N), according to the set horizontal viewing angle range, each emitting device and each reflector of the nth group of emitting units cooperate to generate a point cloud array, forming a total of M×L point cloud arrays. According to the vertical resolution distribution, the nth vertical field of view point cloud set is generated, where n is a positive integer less than or equal to N.
[0008] The N groups of luminescent units correspond to N vertical field-of-view point cloud sets, which are distributed along the vertical direction to form a frame of point cloud dataset.
[0009] In one embodiment of this application, the rotating mirror rotates one revolution, and the L-face mirrors act on the same emitting device to generate L point cloud arrays distributed according to the vertical resolution.
[0010] In one embodiment of this application, the pitch angles of the L-face reflectors relative to the rotation axis of the rotating mirror are different, and the pitch angle difference between adjacent reflectors corresponds to the vertical resolution.
[0011] In one embodiment of this application, the emission positions or laser emission angles of the M emitting devices are distributed in the vertical direction, and the point cloud array generated by the (m-1)th emitter and the mth emitter is distributed in the vertical direction according to the vertical resolution × L.
[0012] In one embodiment of this application, the N groups of emitting units work in turn, with the rotation period being N times the rotation period of the rotating mirror; and / or, the M laser emitting devices in any group of emitting units work sequentially or simultaneously within one rotation period of the rotating mirror.
[0013] In one embodiment of this application, the rotation speed of the rotating mirror is adjusted so that the product of the time difference between adjacent point cloud arrays and the moving speed of the target under test is less than a set distortion threshold.
[0014] On the other hand, this application also proposes a lidar for implementing the method described in the first aspect of this application. The lidar includes a rotating mirror, a transceiver module, and a control module. The transceiver module includes N groups of transmitting units arranged vertically, each group of transmitting units including M transmitting devices arranged horizontally. The rotating mirror includes a vertically rotating axis and an L-shaped reflector rotating around the rotating axis.
[0015] The control module is electrically connected to the transceiver module and the rotating mirror, respectively, and is used to control the N sets of transmitting units to emit light and drive the rotating mirror to rotate.
[0016] When the nth group of emitting units emits light, each emitting device and each reflector of the nth group of emitting units cooperate to generate a point cloud array according to the set horizontal viewing angle range, generating a total of M×L point cloud arrays. Distributed according to the vertical resolution, the nth vertical field of view point cloud set is generated. The N groups of emitting units correspond to N vertical field of view point cloud sets, and the N vertical field of view point cloud sets are distributed along the vertical direction to form a frame point cloud dataset.
[0017] In one embodiment of this application, the pitch angle of each of the L-face mirrors is adjustable; the pitch angles of the L-face mirrors relative to the rotation axis of the rotating mirror are different, and the difference in pitch angle between adjacent mirrors corresponds to the vertical resolution.
[0018] In one embodiment of this application, the horizontal field of view of the L-face reflectors is the same.
[0019] Thirdly, embodiments of this application also provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in any embodiment of this application.
[0020] The above-described technical solutions adopted in the embodiments of this application can achieve the following beneficial effects:
[0021] This paper proposes a lidar scanning method that first forms a local vertical field of view, then sequentially forms multiple local vertical fields of view, and finally stitches them together to form the entire vertical field of view. The multi-line point cloud array constructed by this method has small inter-row time difference, reducing motion distortion.
[0022] The point cloud scanning scheme using this approach has the following characteristics: for small moving targets, there is no motion distortion within a local vertical field of view; for large moving targets, the point cloud in multiple local vertical fields of view exhibits a linear tilt, making it easier to correct motion distortion between adjacent local vertical fields of view through software processing.
[0023] The point cloud scanning scheme of this application achieves high-line-count point cloud data acquisition while using fewer lasers, thus reducing equipment power consumption. In some embodiments of this application, equipment power consumption is further reduced by controlling the laser operating time. Attached Figure Description
[0024] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:
[0025] Figure 1 This is a schematic diagram of an embodiment of the device of this application;
[0026] Figure 2 This is an embodiment of the method of this application;
[0027] Figure 3 This is a schematic diagram of the field-of-view point cloud array stitching in this application;
[0028] Figure 4 This is a schematic diagram of an embodiment of the device of this application that includes a control module;
[0029] Figure 5 This is a schematic diagram of the structure of an electronic device provided in this application. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.
[0032] Figure 1 This is a schematic diagram of an embodiment of the device described in this application. This application proposes a lidar system, including a rotating mirror and a transceiver module; the transceiver module includes N groups of transmitting units arranged vertically, each group of transmitting units including M transmitting devices arranged horizontally; the rotating mirror includes an L-shaped reflector arranged along a vertical rotation axis and an L-shaped reflector arranged in the rotation angular direction. In this application... Figure 3 In the embodiment shown, N=4, M=8, L=4.
[0033] The axis of rotation is the same as the arrangement direction of the N sets of transmitting units. For ease of explanation, in all embodiments of this application, the vertical direction can also be described as a first direction, and the horizontal direction can be described as a second direction. Those skilled in the art will understand that the first direction can also be a horizontal direction, and the second direction can also be a vertical direction. Therefore, in any embodiment of this application, the vertical direction can be described as the second direction, and the horizontal direction can be described as the first direction, all of which fall within the scope of protection of this application.
[0034] In the operation of the device of this application, the first group of transmitting units of the transmitting module rotates once through the rotating mirror module to form the first circle of point cloud data, which corresponds to the first vertical field of view of the lidar; ...; the Nth group of transmitting units of the transmitting module rotates once through the rotating mirror module to form the Nth circle of point cloud data, which corresponds to the Nth vertical field of view of the lidar.
[0035] Each rotation of the rotating mirror module creates an M×L point cloud channel through the L-face reflector, meaning that any given vertical field of view is composed of M×L point cloud channels. Each transmitting device has an L-channel point cloud channel formed by the L-face reflector that is vertically adjacent, and each channel covers the horizontal field of view angle.
[0036] The first vertical field of view, ..., the Nth vertical field of view are sequentially stitched together to form the vertical field of view of the lidar, forming a complete frame of point cloud data. Therefore, the vertical field of view of the lidar consists of N×M×L point cloud channels. Each point cloud channel contains a set of point cloud array data.
[0037] Each group of emitting units contains M emitting devices. Adjacent emitting devices emit lasers simultaneously or sequentially at a set time interval to ensure that the light emission start time interval of the emitting devices in each group of emitting units is minimized.
[0038] Figure 2 This is an embodiment of the method of this application. The laser scanning method proposed in this application is used for... Figure 1 The apparatus shown includes the following steps:
[0039] Step 21: Determine the pitch angle of each mirror in the rotating mirror so that the point cloud data scanned by multiple mirrors are separated in the vertical direction.
[0040] In one embodiment of this application, the pitch angles of the L-plane reflectors are adjusted to be different, and the pitch angle difference between adjacent reflectors corresponds to the vertical resolution of the point cloud. For example, in Figure 3 In the point cloud frame shown, the first row of point cloud data is generated by the first rotating mirror and the first transmitting device in the first group of transmitting units, and the second row of point cloud data is generated by the second rotating mirror and the first transmitting device in the first group of transmitting units. Due to the difference in the pitch angles of the first and second rotating mirrors, the first and second rows of point cloud data are separated in the vertical direction. The difference in position (which can be represented by a vertical angle) between the two rows of data corresponds to the vertical resolution of the point cloud. In this application, the point cloud array is referred to as a "line," and the number of point cloud rows in the vertical field of view is referred to as the "line count."
[0041] Step 22: Drive the rotating mirror to obtain multiple sets of point cloud array data, generate multiple vertical field-of-view point cloud sets, and each vertical field of view corresponds to a set of emission units.
[0042] When the horizontal rotating mirror (i.e., the rotating mirror) rotates for the nth revolution (n = 1 to N), the nth group of emitting units emits light. According to the set horizontal viewing angle range, each emitting device of the nth group of emitting units and each reflector cooperate to generate a point cloud array, generating a total of M×L point cloud arrays. According to the vertical resolution distribution, the nth vertical field-of-view point cloud set is generated. This further includes the following steps:
[0043] In one embodiment of this application, during each rotation of the horizontal rotating mirror, the L-face mirrors act on the same emitting device to generate L point cloud arrays distributed according to the vertical resolution.
[0044] In one embodiment of this application, the light emission positions or laser emission angles of the M emitting devices in each group of emitting units are distributed in the vertical direction, and the point cloud array generated by the (m-1)th emitter and the mth emitter is distributed in the vertical direction according to the vertical resolution × L.
[0045] In one embodiment of this application, the rotation speed of the rotating mirror is adjusted so that the product of the time difference between adjacent point cloud arrays and the moving speed of the target under test is less than a set distortion threshold. Adjacent point cloud arrays are generated by the same laser emitting device through adjacent mirrors. As the rotating mirror module rotates one revolution, the higher the rotation speed, the smaller the time difference between two adjacent rotating mirrors; that is, the smaller the point cloud deformation corresponding to two adjacent rotating mirrors in one revolution, i.e., the smaller the motion distortion. In other words, this ensures that the starting time interval between adjacent line emission is as small as possible.
[0046] Step 23: Control the emission of multiple groups of emission units to work in turn, and to make multiple lasers in each group of emission units work sequentially or simultaneously.
[0047] Preferably, the N groups of emitting units work in rotation, and the rotation period refers to the time required for all N groups of emitting units to complete one detection cycle. That is, within one rotation period, the N groups of emitting units complete the emission detection in sequence, and the corresponding rotating mirror rotates N times. The rotation period is N times the rotation period of the rotating mirror.
[0048] Preferably, the M laser emitting devices in any group of emitting units can emit light sequentially, in groups, or simultaneously within one rotation cycle of the horizontal rotating mirror. It should also be noted that the M laser emitting devices in any group of emitting units can emit lasers simultaneously in a set order or sequentially at a set minimum time interval. However, the more devices emit simultaneously, the greater the crosstalk effect. The minimum time interval is related to the radar range; as the lidar ranging distance increases, the minimum time interval also increases to ensure that laser transmission and reflected laser acquisition can be completed within the minimum time interval.
[0049] Step 24: Frame the point cloud array based on the vertical field of view.
[0050] The N groups of luminescent units correspond to N vertical field-of-view point cloud sets, which are distributed along the vertical direction to form a frame of point cloud dataset.
[0051] In the embodiments of steps 21 to 24, the transmitting module is divided into N groups of transmitting units. Each group of transmitting units (including M transmitting devices) rotates once through the rotating mirror module to form a ring of point cloud, thus forming a local vertical field of view. The N groups of transmitting units sequentially form N rings of point cloud, that is, N different local vertical fields of view; the N rings of point cloud are pieced together to form a complete frame of point cloud data, that is, to form a complete vertical field of view.
[0052] Figure 3 This is a schematic diagram of the field-of-view point cloud array stitching in this application.
[0053] Multi-line lidar, such as the common 128-line lidar, typically uses 32 laser transceivers, achieved through four reflectors, resulting in 32 × 4 = 128 lines in the vertical direction. A common frame rate is 10Hz, meaning the time for one rotation of the reflector module is 100ms; the time for each reflector within one rotation is 25ms. Each reflector corresponds to the same horizontal field of view, for example, 120°. The four reflectors complete the vertical field of view (FOV) stitching.
[0054] Assuming the relative speed between the lidar and the target is 100 km / h, the distortion between two adjacent mirrors due to the motion is: 100 km / h × 25 ms = 69 cm;
[0055] If the rotation speed of the horizontal rotating mirror is increased to 2400 r / min, the time for the reflector module to complete one revolution is 25 ms, and the time corresponding to each reflector in one revolution is 25 ms / 4 = 6.25 ms; similarly assuming that the relative speed between the lidar and the target is 100 km / h, the distortion between two adjacent reflectors due to the motion is: 100 km / h × 6.25 ms = 17.36 cm;
[0056] Increasing the rotation speed of the horizontal rotating mirror and making adjacent laser emitting units emit light simultaneously or with the minimum time interval can effectively optimize the motion distortion caused by the stitching of the mirror point cloud.
[0057] like Figure 3 As shown: Each black dot represents the starting position of a rotating mirror. The smaller the interval between the starting positions of each rotating mirror (the faster the rotation speed, the smaller the interval), and the laser emitting units of adjacent channels in the corresponding point cloud emit light simultaneously or at the minimum time interval, the target object will be slightly trapezoidal in shape during the relative motion between the lidar and the target object, with minimal deformation. This can effectively optimize the motion distortion caused by the splicing of the mirror point cloud.
[0058] Considering that the horizontal angular resolution of the lidar is 0.1° and the ranging capability is 200m, the round-trip flight time of the laser is approximately t = 1.34us;
[0059] When the horizontal rotating mirror rotates at 600 r / min, the time taken for the lidar to rotate 0.1° is 13.89 μs; 13.89 / 1.34 = 10.3, meaning that a maximum of 10 laser beam transmissions and receptions can be performed within one horizontal resolution cycle; however, in reality, considering the stability of the circuit signal, the actual number of emission times should be less than 10, for example, 8 times, to achieve 8-line scanning; for 32 laser transceivers, considering 8 emission times within one horizontal resolution cycle, each emission requires driving 4 lasers to emit, that is, 4 lasers are emitting simultaneously, and the motor drives the rotating mirror to rotate 1 revolution to form one frame of point cloud;
[0060] When the horizontal rotating mirror rotates at 2400 r / min, the time taken for the lidar to rotate 0.1° is 3.47 μs; 3.47 / 1.34 = 2.5 μs. One horizontal resolution cycle emits light twice. Considering that there are 4 lasers emitting light simultaneously, 32 lasers transmitting and receiving / 2 times / 4 = 4. That is, the motor needs to rotate 4 times to complete all 32 lasers transmitting and receiving. In other words, when the horizontal rotating mirror rotates at 2400 r / min, the motor drives the rotation 4 times to stitch together one frame of point cloud.
[0061] Figure 4 This is a schematic diagram of an embodiment of the device of this application that includes a control module. On the other hand, this application also proposes a lidar for implementing the method described in the first aspect of the application. The multi-line lidar includes a rotating mirror and a transceiver module. The transceiver module includes N groups of transmitting units arranged vertically, each group of transmitting units including M transmitting devices arranged horizontally; the rotating mirror includes a vertical rotation axis and an L-shaped reflector that rotates around the rotation axis (arranged along the rotation angle direction).
[0062] In one embodiment of this application, each of the L-face mirrors has an adjustable pitch angle in the vertical direction; the pitch angles of the L-face mirrors relative to the rotation axis of the rotating mirror are different, and the difference in pitch angle between adjacent mirrors corresponds to the vertical resolution.
[0063] In one embodiment of this application, the horizontal field of view of the L-face reflectors is the same.
[0064] The lidar also includes a control module 41, which drives the transmitting unit 42 to emit the detection laser and processes the echo signal received by the receiving unit 43 to form point cloud information.
[0065] In the embodiments of this application, the control module is electrically connected to the transceiver module and the rotating mirror, respectively, and is used to control the N sets of transmitting units to emit light and drive the rotating mirror to rotate.
[0066] Further, the control module is used to control: when the horizontal rotating mirror rotates for the nth revolution (n = 1 to N), when the nth group of emitting units emits light, according to the set horizontal viewing angle range, each emitting device of the nth group of emitting units and each reflector cooperate to generate a point cloud array, generating a total of M×L point cloud arrays, distributed according to the vertical resolution, generating the nth vertical field-of-view point cloud set; the N groups of emitting units correspond to N vertical field-of-view point cloud sets, and the N vertical field-of-view point cloud sets are distributed along the vertical direction, forming a frame of point cloud dataset. The transceiver module includes a transmitting unit 42 and a receiving unit 43. The transmitting unit is used to emit a detection laser to the multi-faceted reflector; the receiving unit is used to receive the laser echo signal after the detection laser is reflected by the target object.
[0067] In one embodiment of this application, the control module is further configured to control the emission time of the emitting device, such that within one revolution of the horizontal rotating mirror, the L-face reflectors act on the same emitting device respectively, generating L point cloud arrays distributed according to the vertical resolution.
[0068] In one embodiment of this application, the control module is further configured to control the pitch angles of the L-face reflectors to be different, such that the pitch angle difference between adjacent reflectors corresponds to the vertical resolution. Further, the device includes a rotating mirror 44 for changing the angle of the laser incident on the multifaceted reflector; the rotating mirror includes a multifaceted reflector and a motor module, the multifaceted reflector being fixed to the motor module and rotating along the axis of the motor module.
[0069] In one embodiment of this application, the control module is further configured to control the emission positions or laser emission angles of the M emitting devices to be distributed in the vertical direction, so that the point cloud array generated by the (m-1)th emitter and the mth emitter is distributed in the vertical direction according to the vertical resolution × L.
[0070] In one embodiment of this application, the control module is further configured to control the N groups of emitting units to work in rotation, with the rotation period being N times the rotation period of the rotating mirror. It can be understood that within one rotation period, each of the N groups of emitting units completes one detection cycle; that is, the N groups of emitting units sequentially complete the emission detection, and the corresponding rotating mirror rotates N times.
[0071] In one embodiment of this application, the control module is further configured to control the M laser emitting devices in any group of emitting units to emit light sequentially, in groups, or simultaneously within one rotation cycle of the horizontal rotating mirror. When emitting light sequentially or in groups, the corresponding laser emitting device is driven to emit light according to the minimum time interval.
[0072] In one embodiment of this application, the control module can drive the motor module, and the rotational speed of the motor module is adjustable. The control module is also used to adjust the rotational speed of the rotating mirror, such that the product of the time difference between adjacent point cloud arrays and the moving speed of the target under test is less than a set distortion threshold.
[0073] Preferably, increasing the rotational speed of the motor module will result in a smaller time interval between two adjacent rotating mirrors when the motor module rotates one revolution; that is, the point cloud deformation corresponding to two adjacent rotating mirrors will be smaller in one revolution of point cloud, i.e., the motion distortion will be smaller.
[0074] Preferably, by using the laser radar point cloud scanning method and simultaneously increasing the rotational speed of the motor module, the motion distortion problem caused by the point cloud splicing scheme of the multi-faceted reflector can be optimized.
[0075] To this end, this application also proposes a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the methods described in any embodiment of this application.
[0076] Furthermore, this application also proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in any embodiment of this application.
[0077] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device 50 shown is merely an example and should not be construed as limiting the functionality or scope of use of the embodiments of this application. It includes: one or more processors 52; and a storage device 51 for storing one or more programs, which, when executed by the one or more processors 52, cause the one or more processors 52 to implement the method provided in the embodiments of this application, the method including the control process described in steps 21-24:
[0078] The electronic device 50 also includes an input device 53 and an output device 54; the processor 52, storage device 51, input device 53 and output device 54 in the electronic device can be connected by a bus or other means, and the connection via bus 55 is taken as an example in the figure.
[0079] Storage device 51, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and module units, such as the program instructions corresponding to the cloud bottom height determination method in the embodiments of this application. Storage device 51 may mainly include a program storage area and a data storage area, wherein the program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created based on terminal usage, etc. Furthermore, storage device 51 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some instances, storage device 51 may further include memory remotely located relative to processor 52, and these remote memories can be connected via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.
[0080] Input device 53 can be used to receive input digital, character, or voice information, and to generate key signal inputs related to user settings and function control of the electronic device. Output device 54 may include electronic devices such as a display screen and a speaker.
[0081] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0082] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.
Claims
1. A scanning method for a lidar, characterized in that, The lidar includes a rotating mirror and a transceiver module; the transceiver module includes N sets of transmitting units arranged vertically, each set of transmitting units including M transmitting devices arranged horizontally; the rotating mirror includes a vertical rotation axis and an L-shaped reflector rotating around the rotation axis; the method includes: The N sets of emitting units are driven to emit light, and the rotating mirror is driven to rotate. When the nth group of emitting units emits light, each emitting device and each reflector of the nth group of emitting units, according to the set horizontal viewing angle range, cooperate to generate a point cloud array, forming a total of M×L point cloud arrays, which are distributed according to the vertical resolution to form the nth first field of view point cloud set; where n is a positive integer less than or equal to N; The N groups of luminescent units correspond to N first field-of-view point cloud sets, which are distributed along the vertical direction to form a frame of point cloud dataset.
2. The scanning method as described in claim 1, characterized in that, The pitch angles of the L-face mirrors relative to the rotation axis of the rotating mirror are different, and the pitch angle difference between adjacent mirrors corresponds to the vertical resolution.
3. The scanning method as described in claim 2, characterized in that, The emission positions or laser emission angles of the M emitting devices are distributed in the vertical direction, and the point cloud array generated by the (m-1)th emitter and the mth emitter is distributed in the vertical direction according to the vertical resolution × L.
4. The scanning method as described in claim 1, characterized in that, The N sets of transmitting units operate in rotation, with a rotation period of N times the rotation period of the rotating mirror.
5. The scanning method as described in claim 1, characterized in that, The M laser emitting devices in any group of emitting units operate sequentially or simultaneously within one rotation cycle of the rotating mirror.
6. The scanning method as described in claim 1, characterized in that, The rotation speed of the rotating mirror is adjusted so that the product of the time difference between adjacent point cloud arrays and the moving speed of the target under test is less than the set distortion threshold.
7. A lidar, characterized in that, Includes a rotating mirror, a transceiver module, and a control module; The transceiver module includes N sets of transmitting units arranged in a vertical direction, and each set of transmitting units includes M transmitting devices arranged in a horizontal direction. The rotating mirror includes a rotation axis in a vertical direction and an L-shaped reflector that rotates around the rotation axis. The control module is electrically connected to the transceiver module and the rotating mirror, respectively, and is used to control the n groups of emitting units to emit light and drive the rotating mirror to rotate. When the nth group of emitting units emits light, each emitting device and each reflector in the nth group of emitting units cooperate to generate a point cloud array according to the set horizontal viewing angle range, generating a total of M×L point cloud arrays. The point cloud sets are distributed according to the vertical resolution to generate the nth vertical field of view point cloud set. The N groups of emitting units correspond to N vertical field of view point cloud sets, and the N vertical field of view point cloud sets are distributed along the vertical direction to form a frame point cloud dataset.
8. The multi-line lidar as described in claim 7, characterized in that, The pitch angles of the L-face reflectors relative to the rotation axis of the rotating mirror are all different, and the difference in pitch angle between adjacent reflectors corresponds to the vertical resolution.
9. The multi-line lidar as described in claim 7, characterized in that, The horizontal field of view of the L-face mirrors is the same.
10. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method as described in any one of claims 1-6.