A multi-line laser radar and its data point cloud processing method

Abstract

The present invention relates to a multi-line laser radar and a data point cloud processing method thereof. The multi-line laser radar comprises a rotatable rotating base and a plurality of laser transmitting and receiving modules arranged circumferentially on the rotating base. The laser transmitting and receiving modules comprise: a laser transmitting array comprising a plurality of laser emitters arranged in an array, the laser emitters being configured to emit outgoing laser light, which is reflected by a detection target to produce reflected laser light; and a laser detecting array comprising a plurality of laser detectors arranged in an array, the laser detectors being configured to receive the reflected laser light. The plurality of laser emitters arranged circumferentially between the plurality of laser transmitting arrays included in the plurality of laser transmitting and receiving modules have different emission angles. The multi-line laser radar and the data point cloud processing method thereof of the present invention can improve the detection accuracy of the multi-line laser radar.

Description

Technical Field

[0001] The present invention generally relates to the field of laser technology. More specifically, the present invention relates to a multi-line laser radar and a data point cloud processing method thereof. Background Art

[0002] With the continuous development of laser technology, it is increasingly being applied in various aspects of life, such as laser measurement. The basic principle of lidar is to emit a laser beam toward a target, receive the reflected beam, and calculate the round-trip time of the laser to determine the distance between the lidar and the target. Multi-line lidar emits multiple laser beams and compares the received reflected beams to obtain information such as the target's distance, height, speed, shape, and size.

[0003] Currently, multi-line LiDAR is widely used to detect targets. However, its detection accuracy is related to the number of laser beams, which is limited by the size of the LiDAR. Consequently, traditional multi-line LiDARs generally suffer from low accuracy or bulk. Furthermore, the point cloud data generated by traditional multi-line LiDARs is modeled based on each laser source, resulting in low accuracy.

[0004] Therefore, it is necessary to develop a multi-line laser radar with higher precision and smaller size to improve the problems of low precision and large size in traditional multi-line laser radars; and to make the obtained point cloud information of the detected object data more accurate. Summary of the Invention

[0005] In order to solve one or more of the technical problems mentioned above, the present invention provides a multi-line laser radar and a data point cloud processing method thereof to improve the problems of poor detection accuracy and large size of traditional multi-line laser radar.

[0006] In a first aspect, an exemplary embodiment of the present invention provides a multi-line laser radar, which may include a rotatable rotating base and a plurality of laser transmitting and receiving modules arranged circumferentially on the rotating base, the laser transmitting and receiving modules may include: a laser transmitting array, which includes a plurality of laser emitters arranged in an array, the laser emitters are used to emit outgoing lasers, and the outgoing lasers are reflected by the detection target to generate reflected lasers; and a laser detection array, which includes a plurality of laser detectors arranged in an array, the laser detectors are used to receive the reflected lasers, wherein, between the plurality of laser transmitting arrays included in the plurality of laser transmitting and receiving modules, the plurality of laser emitters arranged correspondingly in the circumferential direction may have different emission angles respectively.

[0007] In an exemplary embodiment, between the multiple laser emitting arrays included in the multiple laser emitting and receiving modules, the multiple laser emitters correspondingly arranged along the circumferential direction may have different heights.

[0008] In an exemplary embodiment, the number of the laser detectors may be the same as the number of the laser emitters, and the plurality of laser detectors may respectively have angles and heights corresponding to the plurality of laser emitters.

[0009] In an exemplary embodiment, all laser emitters may have different emission angles.

[0010] In an exemplary embodiment, the laser transmitting and receiving module may further include: an optical receiving structure, which includes a receiving lens, the receiving lens is used to collect reflected laser and make the collected reflected laser incident on a corresponding laser detector; and / or an optical output structure, which includes an emitting lens, the emitting lens is arranged around the receiving lens, and is used to collect the output laser emitted by the laser transmitter.

[0011] In an exemplary embodiment, the optical emission structure may include at least four emitting lenses, and the optical receiving structure may include at least one receiving lens, wherein the at least four emitting lenses may be arranged on one side of the receiving lens.

[0012] In an exemplary embodiment, the multiple laser transmitting and receiving modules may include: a first laser transmitting and receiving module, a second laser transmitting and receiving module, a third laser transmitting and receiving module and a fourth laser transmitting and receiving module, wherein the first laser transmitting and receiving module and the third laser transmitting and receiving module are centrally symmetrical structures, the second laser transmitting and receiving module and the fourth laser transmitting and receiving module are centrally symmetrical structures, the first laser transmitting and receiving module and the second laser transmitting and receiving module are axially symmetrical structures, and the third laser transmitting and receiving module and the fourth laser transmitting and receiving module are axially symmetrical structures.

[0013] In an exemplary embodiment, the laser emission array may further include an emission board, on which a plurality of laser emitters arranged in an array are disposed, and the laser detection array may further include a receiving board, on which a plurality of laser detectors arranged in an array are disposed.

[0014] In an exemplary embodiment, the laser emission array may further include a light source driving device and at least four laser emitters electrically connected to the light source driving device; the laser detection array may further include a signal processing device and at least four laser detectors electrically connected to the signal processing device; and the laser detectors may correspond one-to-one to the laser emitters respectively.

[0015] In an exemplary embodiment, the multi-line laser radar may further include a motor, a top plate and a light barrier, wherein the motor is connected to the rotating base so that the rotating base rotates under the drive of the motor; the top plate is arranged above the laser emitting and receiving module; and the light barrier is arranged between the multiple laser emitting and receiving modules to separate the multiple laser emitting and receiving modules.

[0016] In an exemplary embodiment, the multi-line laser radar may further include a control device connected to the motor to control the rotation of the rotating base through the motor.

[0017] In an exemplary embodiment, the multi-line laser radar may further include an orientation detection device configured to determine the orientation of the target, including: determining the round-trip time T of the laser between the target and the laser radar; determining a first angle α between the laser and a predetermined plane in a predetermined coordinate system; determining a rotation angle β of the laser emitter with the rotating base; and determining the orientation of the target based on the round-trip time T, the position of the laser emitter in the predetermined coordinate system, the first angle α and the rotation angle β.

[0018] In a second aspect, an exemplary embodiment of the present invention provides a data point cloud processing method for a multi-line lidar described in the first aspect and its various embodiments, the method may include: determining a round-trip time T of the laser between the target and the lidar; determining a first angle α between the laser and a predetermined plane in a predetermined coordinate system; determining a rotation angle β of the laser emitter with the rotating base; and determining the orientation of the target based on the round-trip time T, the position of the laser emitter in the predetermined coordinate system, the first angle α and the rotation angle β.

[0019] As described above, the laser radar of an exemplary embodiment of the present invention can arrange multiple laser transmitting and receiving modules on a rotating base, and the multiple laser emitters included in these laser transmitting and receiving modules can have different emission angles, thereby increasing the number of pixel points on the detection target, thereby significantly improving the resolution of the laser radar.

[0020] In addition, the laser radar of an exemplary embodiment of the present invention can increase the number of laser emitters without increasing the height of the laser transmitting and receiving modules by setting the multiple laser emitters included in the multiple laser transmitting and receiving modules to have different heights. Therefore, the laser radar of the present invention can improve the resolution of the laser radar without increasing the overall height of the laser radar, thereby reducing the volume of the laser radar.

[0021] Furthermore, the multi-line laser radar and its data point cloud processing method of the present invention can establish a three-dimensional rectangular coordinate system using the laser radar's rotation axis as the z-axis. This allows the pixels generated by the laser radar's multiple laser transmitting and receiving modules to be calculated within the same predetermined coordinate system, and the data point cloud of the detected target can be drawn within the same predetermined coordinate system. Therefore, the multi-line laser radar and its data point cloud processing method of the present invention can improve the laser radar's detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present invention are shown in an illustrative and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0023] Figure 1 is a schematic diagram illustrating a multi-line laser radar according to an exemplary embodiment of the present invention;

[0024] Figure 2 is a schematic diagram illustrating a laser emission array of a multi-line laser radar according to an exemplary embodiment of the present invention;

[0025] Figure 3 is a schematic diagram showing an equivalent layout of a laser transmitter of a multi-line laser radar according to an exemplary embodiment of the present invention;

[0026] Figure 4 is a schematic diagram illustrating a laser emission array of a multi-line laser radar according to another exemplary embodiment of the present invention;

[0027] Figure 5 is a schematic diagram illustrating a laser emission array of a multi-line laser radar according to another exemplary embodiment of the present invention;

[0028] Figure 6 is a schematic diagram illustrating an optical emission structure and an optical receiving structure of a multi-line laser radar according to an exemplary embodiment of the present invention;

[0029] Figure 7 is a schematic diagram illustrating a multi-line laser radar measuring a target detection object according to an exemplary embodiment of the present invention; and

[0030] Figure 8 3 is a flowchart illustrating a method for processing a data point cloud of a multi-line laser radar according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0032] It should be understood that the terms "first," "second," "third," and "fourth," etc. in the claims, description, and drawings of the present invention are used to distinguish different objects, rather than to describe a specific order. The terms "comprise" and "comprising" used in the description and claims of the present invention indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0033] It should also be understood that the terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present invention. As used in the specification and claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should further be understood that the term "and / or" as used in the specification and claims refers to any and all possible combinations of one or more of the associated listed items, including and including these combinations.

[0034] As used in this specification and claims, the term "if" can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0035] Multi-line lidar is a type of lidar that uses multiple laser transmitters to emit lasers to detect the position, speed and other characteristic quantities of the target. Its working principle is to first emit an outgoing laser to the target, then receive the reflected laser reflected from the detected target and compare it with the outgoing laser, thereby obtaining relevant information about the target.

[0036] Currently, traditional multi-line LiDARs typically implement multi-line laser detection by installing multiple laser emitters and multiple laser detectors on a transmitting board and a receiving board, respectively. The system utilizes the laser light emitted by these multiple laser emitters for detection. However, the number of laser lines in a multi-line LiDAR determines its detection accuracy. Increasing the number of laser lines typically involves simply adding more laser emitters on the transmitting board, which in turn increases the size of the transmitting board and the corresponding optical structure, thus increasing the size of the LiDAR.

[0037] Furthermore, increasing the number of laser emitters on the transmitter board increases their density, making them more difficult to debug. Therefore, simply increasing the number of laser emitters to increase the number of lines is limited by the overall size of the LiDAR and the difficulty of adjusting the LiDAR angle, making it difficult to improve LiDAR detection accuracy.

[0038] In response to the above problems, an exemplary embodiment of the present invention provides a multi-line laser radar, which may include at least one rotating base and at least two laser transmitting and receiving modules arranged on the rotating base. The laser transmitting and receiving modules may include: a laser transmitting array, a laser detecting array, an optical emitting structure and an optical receiving structure, wherein the laser transmitting array may include: a receiving plate, a laser emitter and a collimating cylinder, and the laser detecting array may include: a receiving plate and a laser detector.

[0039] The multi-line laser radar of the present invention utilizes multiple laser emitters arranged at different vertical angles and positions to emit laser light. After being collimated by a collimator, the emitted laser light is emitted through the corresponding transmitting lens. Upon encountering the detection target, it is reflected to produce reflected laser light. The reflected laser light is converged by a receiving lens and detected by laser detectors arranged at different vertical angles and positions, corresponding to each laser emitter.

[0040] Furthermore, the multi-line laser radar of the present invention uses a timing unit and an orientation detection device to determine laser beam information related to ranging, thereby calculating three-dimensional data point cloud information of the detected target relative to the laser radar's rotation axis. The multi-line laser radar of the present invention not only effectively improves the resolution of the multi-line laser radar while maintaining a smaller overall size, but also accurately calculates and processes three-dimensional data point cloud information of the detected target.

[0041] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0042] Figure 1 is a schematic diagram illustrating a laser radar according to an exemplary embodiment of the present invention.

[0043] like Figure 1As shown, an exemplary embodiment of the present invention provides a laser radar, which may include: a rotatable rotating base 100 and a plurality of laser emitting and receiving modules 200 arranged circumferentially on the rotating base 100. Specifically, the laser emitting and receiving modules 200 may include: a laser emitting array 210a-210d, which includes a plurality of laser emitters 211 arranged in an array, and the laser emitters 211 are used to emit outgoing laser light, which is reflected by a detection target to generate reflected laser light; and a laser detecting array 220a-220d, which includes a plurality of laser detectors 221 arranged in an array, and the laser detectors 221 are used to receive the reflected laser light.

[0044] Specifically, if Figure 1 As shown, the above-mentioned laser emitting array 210a-210d may include a plurality of laser emitters 211, and the plurality of laser emitters 211 may emit outgoing lasers toward the outside of the laser radar. When the outgoing lasers encounter the detection target, they will be reflected to produce reflected lasers, and the reflected lasers may be received by the laser detector 221 on the laser detection array arranged near the laser emitting array 210a-210d, thereby realizing laser detection.

[0045] Figure 2 is a schematic diagram illustrating a laser emission array of a multi-line laser radar according to an exemplary embodiment of the present invention.

[0046] Further Figure 2 As shown, each of the plurality of laser emission arrays 210a-210d includes a plurality of laser emitters 211 spaced apart along a first direction, wherein the first direction is parallel to the rotation axis of the laser radar. Figure 2 In the embodiment shown, the first direction is Figure 2 The vertical direction in .

[0047] In particular, if Figure 2 As shown, between the multiple laser emitting arrays 210a-210d included in the multiple laser emitting and receiving modules 200, the multiple laser emitters 211 arranged in a corresponding circumferential direction can each have different emission angles. Here, the emission angle refers to the angle between the outgoing laser light emitted by the laser emitter 211 and a first plane, which is a plane perpendicular to the rotation axis of the laser radar.

[0048] Specifically, in Figure 2 The figure shows a plurality of laser emitting arrays 210a-210d included in a plurality of laser emitting and receiving modules 200, wherein a plurality of laser emitters 211 are arranged correspondingly along the circumferential direction between the plurality of laser emitting arrays 210a-210d. Figure 2As shown in FIG, four laser emitters 211 are arranged correspondingly along the horizontal direction. Figure 2 The figure shows four rows of corresponding laser emitters 211, each row including four laser emitters. The four laser emitters in each row can have different emission angles. It will be appreciated that this arrangement allows each of the corresponding laser emitters 211 arranged circumferentially to generate a pixel on the detected target when the lidar rotates, thereby increasing the number of pixels generated on the detected target.

[0049] Therefore, it can be understood that the multi-line laser radar disclosed in the present invention can achieve scanning ranging in a 360° field of view when the laser radar is rotated by setting the multiple laser emitters arranged correspondingly in the circumferential direction on the multiple laser emission arrays to have different emission angles, thereby increasing the number of pixel points that enter the detection target and thus improving the resolution of the laser radar.

[0050] Further, continue to refer to Figure 2 In an exemplary embodiment, between the multiple laser emitting arrays 210a-210d included in the multiple laser emitting and receiving modules 200, the multiple laser emitters 211 correspondingly arranged along the circumferential direction can have different heights.

[0051] Specifically, similar to the emission angles described above, Figure 2 As shown, a total of four rows of correspondingly arranged laser emitters 211 are shown, each row includes four laser emitters 211, and the four laser emitters 211 in each row can have different heights. Here, it can be understood that the height is Figure 2 The height along the vertical direction, which is parallel to the rotation axis of the multi-line lidar.

[0052] Therefore, it can be understood that the above arrangement can enable the multiple laser emitters 211 arranged correspondingly along the circumferential direction to each generate a pixel point on the detection target when the laser radar rotates, thereby increasing the number of pixel points generated on the detection target.

[0053] Furthermore, it is understandable that although Figure 2 The embodiment shown includes four rows of corresponding laser emitters 211, with each row including four laser emitters 211. However, this arrangement is only a preferred embodiment of the present disclosure. Regarding the number of rows and the number of laser emitters included in each row, those skilled in the art may select a different number of rows and the number of laser emitters included in each row based on the application scenario, and the present disclosure does not limit this.

[0054] Furthermore, in an exemplary embodiment, all laser emitters can have different emission angles. In other words, each of the laser emitters included in the multi-line laser radar of the present disclosure can have a different emission angle. This arrangement allows each laser emitter 211 to generate a pixel on the detected target, thereby further increasing the number of pixels generated on the detected target.

[0055] In an exemplary embodiment, Figure 1 As shown, the multi-line laser radar of the present invention may illustratively include four laser emitting and receiving modules 200. The four laser emitting and receiving modules 200 may include: a first laser emitting and receiving module 200a, a second laser emitting and receiving module 200b, a third laser emitting and receiving module 200c, and a fourth laser emitting and receiving module 200d. Specifically, the first laser emitting and receiving module 200a and the third laser emitting and receiving module 200c are centrally symmetrical, the second laser emitting and receiving module 200b and the fourth laser emitting and receiving module 200d are centrally symmetrical, the first laser emitting and receiving module 200a and the second laser emitting and receiving module 200b are axially symmetrical, and the third laser emitting and receiving module 200c and the fourth laser emitting and receiving module 200d are axially symmetrical.

[0056] Here, it can be understood that the above-mentioned centrally symmetrical structure of the first laser emitting and receiving module 200a and the third laser emitting and receiving module 200c refers to the symmetry of the overall layout direction of the first laser emitting and receiving module 200a and the third laser emitting and receiving module 200c, and does not mean that the shapes, positions and directions of the various components arranged inside the first laser emitting and receiving module 200a and the third laser emitting and receiving module 200c are also symmetrical to each other.

[0057] Similarly, the second laser emitting and receiving module 200b and the fourth laser emitting and receiving module 200d are centrally symmetrical structures, the first laser emitting and receiving module 200a and the second laser emitting and receiving module 200b are axially symmetrical structures, and the third laser emitting and receiving module 200c and the fourth laser emitting and receiving module 200d are axially symmetrical structures, which also refers to the symmetry of the overall layout direction of the laser emitting and receiving module 200, but is not intended to indicate that the shapes, positions and directions of the various elements arranged inside the laser emitting and receiving module are also symmetrical to each other.

[0058] Therefore, it can be understood that the four laser transmitting and receiving modules 200a-200d arranged as above can respectively detect in four directions of the laser radar, such as Figure 1As shown, and since these laser transmitting and receiving modules 200a-200d are arranged on a rotatable rotating base 100, when the laser radar rotates, each laser transmitting and receiving module can realize scanning ranging under a 360° field of view, thereby increasing the number of laser transmitting and receiving modules used to detect targets, thereby improving the resolution of the laser radar.

[0059] Furthermore, the exemplary embodiment of the present disclosure preferably employs four laser transmitting and receiving modules. Compared to other arrangements, this arrangement not only improves the space utilization of the LiDAR but also simplifies the layout. Therefore, the LiDAR of the present disclosure not only reduces size and improves resolution, but also offers the advantage of being easy to assemble and debug.

[0060] Furthermore, if Figure 1 As shown, the above-mentioned laser emitting and receiving modules 200a-200d may include: a laser emitting array 210a-210d, which includes a plurality of laser emitters 211 arranged in an array, and the laser emitter 211 is used to emit an outgoing laser, and the outgoing laser is reflected by the detection target to generate a reflected laser; and a laser detection array 220a-220d, which includes a plurality of laser detectors 221 arranged in an array, and the laser detectors 221 are used to receive the reflected laser, wherein, among the plurality of laser emitters 211 included in the plurality of laser emitting and receiving modules 200, at least two laser emitters 211 have different emission angles.

[0061] In an exemplary embodiment, Figure 2 As shown, at least two laser emitters 211 among the multiple laser emitters 211 arranged on the same laser emission array may have different emission angles; preferably, each laser emitter 211 may have a different emission angle.

[0062] Specifically, if Figure 2 As shown, the above-mentioned laser emitting array 210a-210d may include multiple laser emitters 211, and the laser emitter 211 may emit outgoing laser toward the outside of the laser radar. The outgoing laser may be reflected when encountering a detection target to generate reflected laser, and the reflected laser may be received by a laser detector 221 on a laser detection array arranged near the laser emitting array 210a-210d, thereby realizing a single laser detection.

[0063] Further Figure 2 As shown, each of the four laser emission arrays 210a-210d includes four laser emitters 211 arranged at intervals in the vertical direction, so the laser radar according to this exemplary embodiment can have a total of sixteen laser emitters 211, and the sixteen laser emitters 211 have different emission angles.

[0064] Furthermore, if Figure 2 As shown, the above four laser emitting arrays 210a-210d can be respectively arranged in the first laser emitting and receiving module 200a, the second laser emitting and receiving module 200b, the third laser emitting and receiving module 200c and the fourth laser emitting and receiving module 200d, so that the sixteen laser emitters 211 do not need to be arranged in the same vertical direction, thereby reducing the overall height of the laser radar and further reducing the volume of the laser radar.

[0065] Figure 3 FIG. 2 is a schematic diagram showing an equivalent layout of the laser emitter 211 of the multi-line laser radar according to an exemplary embodiment of the present invention.

[0066] When the rotating base 100 of the laser radar rotates, the sixteen laser emitters 211 will emit laser beams with different emission angles to the 360° field of view while rotating, and the equivalent layout of the sixteen laser emitters 211 and the equivalent distribution form of the emitted laser beams are as follows: Figure 3 As shown. It can be seen that compared with the traditional laser radar with only one laser transmitting and receiving module, the multi-line laser radar of the present invention can generate sixteen pixel points on the detection target, so the multi-line laser radar of the present invention can significantly improve the resolution of the laser radar.

[0067] Therefore, it can be understood that although the above exemplary embodiment describes a laser radar including four laser transmitting and receiving modules 200a-200d, four laser emitting arrays 210a-210d and sixteen laser emitters 211, the present invention is not intended to limit the number of laser radars. Those skilled in the art can select the number of laser transmitting and receiving modules and laser emitting arrays as needed based on the inventive concepts disclosed in the present invention, and can also select the number of laser emitters included in each laser emitting array as needed.

[0068] In another exemplary embodiment, among the multiple laser emitters 211 included in the multiple laser emitting and receiving modules 200, at least two laser emitters 211 may have different heights; preferably, at least two laser emitters 211 among the multiple laser emitters 211 arranged on the same laser emitting array may have different heights; more preferably, each laser emitter 211 may have a different height.

[0069] It can be understood that in the multi-line laser radar according to this exemplary embodiment, since the laser emitters 211 can be arranged in a vertical direction, and the number of laser emitters 211 can be increased by arranging the laser emitters 211 in a staggered manner, the resolution of the laser radar can be improved without increasing the overall height of the laser radar, and thus the volume of the laser radar can be reduced.

[0070] In one exemplary embodiment, the number of laser detectors 221 can be the same as the number of laser emitters 211, and each of the laser detectors 221 can have a one-to-one correspondence in angle and height with each of the laser emitters 211. Specifically, each of the laser detectors 221 can correspond one-to-one with the outgoing lasers emitted by the laser emitters 211, and each reflected laser generated by an outgoing laser hitting a detection target will be received by a corresponding laser detector 221. This arrangement ensures that each outgoing laser emitted by a laser emitter 211 is received by a corresponding laser detector, thereby improving the detection accuracy of the lidar.

[0071] In an exemplary embodiment, Figure 2 As shown, the laser emission array may further include an emission plate 212, and a plurality of laser emitters 211 arranged in an array may be spaced apart in the vertical direction on the emission plate 212. In addition, the laser detection array may further include a receiving plate 222, and a plurality of laser detectors 221 arranged in an array may be spaced apart in the vertical direction on the receiving plate 222. This arrangement allows for the vertical arrangement of multiple laser emitters 211, thereby increasing the number of laser emitters 211 and improving the detection accuracy of the laser radar.

[0072] In an exemplary embodiment, Figure 2 As shown, the laser emission array may further include a light source driving device and at least four laser emitters 211 electrically connected to the light source driving device. The laser detection array may further include a signal processing device and at least four laser detectors 221 electrically connected to the signal processing device, and the laser detectors 221 may correspond one to one with the laser emitters.

[0073] In an exemplary embodiment, the laser radar may further include: a light emission control device connected to the light source driving device to control the light emission of the laser emitter 211.

[0074] Figure 4 is a schematic diagram showing a laser emission array of a multi-line laser radar according to another exemplary embodiment of the present invention. Figure 4As shown, in this exemplary embodiment, the outgoing laser can be generated by a pulse transmitter, or can be generated by a laser optical fiber in the form of a split line and transmitted to the laser transmitter 211.

[0075] Figure 5 Schematic diagram showing a laser emission array of a multi-line laser radar according to another exemplary embodiment of the present invention. Figure 5 As shown, in this exemplary embodiment, the outgoing laser may also be generated by a pulse transmitter, or may be generated by a laser optical fiber in the form of multiple lines and transmitted to the laser transmitter 211 .

[0076] In an exemplary embodiment, Figure 1 As shown, the laser emitting and receiving modules 200a-200d may further include an optical receiving structure including receiving lenses 230a-230d, which are used to collect reflected laser light and direct the collected reflected laser light to the corresponding laser detector 221. Specifically, the receiving lenses 230a-230d may collect the reflected laser light and converge the reflected laser light to the laser detector 221.

[0077] In an exemplary embodiment, Figure 1 As shown, the laser emitting and receiving modules 200a-200d may further include: an optical emission structure, which includes an emitting lens 240a-240d, which is arranged around the receiving lens 230a-230d and is used to collect the outgoing laser emitted by the laser emitter 211. In an application scenario, such as Figure 1 As shown, each of the multiple laser transmitting and receiving modules 200a-200d can include at least four transmitting lenses 240a-240d and at least one receiving lens 230a-230d, and the above-mentioned at least four transmitting lenses 240a-240d can be arranged at the upper right, lower right, upper left and lower left of the receiving lens 230a-230d respectively.

[0078] Figure 6 Schematic diagram showing an optical emission structure and an optical receiving structure of a multi-line laser radar according to an exemplary embodiment of the present invention.

[0079] In an exemplary embodiment, Figure 6As shown, the optical emission structure may include at least four emission lenses 240a-240d, and the optical receiving structure may include at least one receiving lens 230a-230d. The at least four emission lenses 240a-240d may be arranged on one side of the receiving lenses 230a-230d and correspond one-to-one with the laser emitters 211. The laser light emitted by the laser emitters 211 may be collimated by the collimator 213 before being emitted through the emission lenses 240a-240d. This arrangement can reduce the difficulty of debugging the emission lenses 240a-240d.

[0080] In an exemplary embodiment, the multi-line laser radar may further include a motor, a top plate and a light baffle 300. Specifically, the above-mentioned motor may be connected to the rotating base 100 of the laser radar so that the rotating base 100 can rotate under the drive of the motor. Further, the above-mentioned top plate may be arranged above the laser emitting and receiving module 200 to form a space for accommodating the laser emitting and receiving module 200 between the top plate and the rotating base 100. Further, the above-mentioned light baffle 300 may be arranged between a plurality of laser emitting and receiving modules 200 to separate a plurality of laser emitting and receiving modules 200, and to isolate the outgoing laser light path and the reflected laser light path of each laser emitting and receiving module 200 from the outgoing laser light path and the reflected laser light path of other laser emitting and receiving modules 200.

[0081] In an exemplary embodiment, the multi-line laser radar may further include a control device that may be connected to the motor to control the rotation of the rotating base 100 via the motor. Specifically, the control device may change the rotation speed of the motor by changing the frequency of the current. When the frequency of the current applied to the motor is increased, the rotation speed of the motor may be increased; and when the frequency of the current applied to the motor is decreased, the rotation speed of the motor may be decreased.

[0082] Therefore, it can be understood that since the rotation speed of the motor can be controlled by the control device, the rotation speed of the rotating base 100 can be obtained by the control device, and the rotation angle of the laser emitter 211 of the laser radar can be calculated based on the rotation speed. For example, the rotation angle of the laser emitter 211 can be calculated by multiplying the angular velocity of the motor by time.

[0083] In an exemplary embodiment, the multi-line laser radar according to an exemplary embodiment of the present invention may further include an azimuth detection device, which is configured to determine the azimuth of the target, including: determining the round-trip time T of the laser between the target and the laser radar; determining the first angle α between the laser and the first plane in a predetermined coordinate system; determining the rotation angle β of the laser emitter 211 as the base 100 rotates; and determining the azimuth of the target based on the round-trip time T, the position of the laser emitter in the predetermined coordinate system, the first angle α and the rotation angle β.

[0084] Figure 7 FIG. 1 is a schematic diagram illustrating a laser radar measuring a target object according to an exemplary embodiment of the present invention.

[0085] Specifically, if Figure 7 As shown, the round trip time T can refer to the time from the laser emitter 211 of the laser radar emitting the outgoing laser to the laser detector 221 receiving the reflected laser. Figure 7 As shown, the predetermined coordinate system can be a three-dimensional rectangular coordinate system with the laser radar's rotation axis as the z-axis. The origin O of the three-dimensional rectangular coordinate system can be selected by those skilled in the art as needed. Specifically, when the laser radar's rotation axis is used as the z-axis of the three-dimensional rectangular coordinate system, the position of the xOy plane of the three-dimensional rectangular coordinate system can be set according to the time application scenario.

[0086] For example, in an application scenario, when the laser radar is arranged vertically on the roof of a vehicle, the rotation axis of the laser radar extends in the vertical direction, so the z-axis of the above-mentioned three-dimensional rectangular coordinate system also extends in the vertical direction. In this way, the xOy plane of the three-dimensional rectangular coordinate system can be selected on the upper surface of the rotating base 100 of the laser radar, or on the surface of the road on which the vehicle travels. This can be set according to actual needs.

[0087] Furthermore, if Figure 7 As shown, the first angle α mentioned above may refer to: the emission angle of the laser emitter 211 of the laser radar, that is, the angle between the outgoing laser emitted by the laser emitter 211 of the laser radar and the xOy plane of the three-dimensional rectangular coordinate system. Figure 7 As shown, the above-mentioned rotation angle β can refer to: when the laser emitter 211 of the laser radar emits the outgoing laser, as the rotating base 100 of the laser radar rotates, it is equal to the angle between the projection of the outgoing laser emitted by the laser emitter 211 of the laser radar on the xOy plane and the x-axis.

[0088] In an exemplary embodiment, the round-trip time T can be determined by a timing unit connected to the laser detector 221. Specifically, the timing unit can record the time when the laser emitter 211 of the laser radar emits the outgoing laser and the time when the laser detector 221 receives the reflected laser, and calculate the difference between the time when the laser detector 221 receives the reflected laser and the time when the laser emitter 211 of the laser radar emits the outgoing laser, so as to obtain the round-trip time T.

[0089] Furthermore, in an exemplary embodiment, the emission angle of each laser emitter 211 can be obtained by configuring the laser emitters 211 of the laser radar to obtain a first angle α between the laser and the first plane in the predetermined coordinate system. It will be appreciated that since the emission angle of the laser emitter 211 can be adjusted as needed, the first angle α between the laser and the first plane in the predetermined coordinate system can also be adjustable or fixed.

[0090] Furthermore, in an exemplary embodiment, the rotation angle β of the laser emitter 211 along with the rotating base 100 can be obtained based on the rotation speed of the rotating base of the laser radar. For example, the rotation angle β can be calculated using the following formula:

[0091] β=w×t

[0092] Wherein, w is the angular velocity of the rotating base 100, and t is the running time.

[0093] Furthermore, in an exemplary embodiment, the three-dimensional coordinates (x, y, z) of each pixel point on the detection target in the above predetermined coordinate system can be calculated using the following formula:

[0094]

[0095] Wherein, h is the distance between the laser emitter 211 and the xOy plane; l x is the distance between the laser emitter 211 and the xOz plane; l y is the distance between the laser emitter 211 and the yOz plane; c is the speed of the laser.

[0096] Furthermore, in an exemplary embodiment, the three-dimensional coordinates (x, y, z) of each pixel point of the lidar in the above-mentioned predetermined coordinate system can be calculated separately, and each pixel point can be drawn in the three-dimensional coordinates, so as to obtain a data point cloud of the detected target.

[0097] It will be appreciated that in this exemplary embodiment, the pixels generated by the multiple laser emitting and receiving modules 200 of the laser radar can be calculated within the same predetermined coordinate system, and the data point cloud of the detected target can be drawn within the same predetermined coordinate system. Therefore, compared to traditional multi-line laser radars that model each laser emitting light source as the center, the laser radar of the present invention can significantly improve the detection accuracy of the laser radar.

[0098] Figure 8 3 is a flowchart illustrating a method for processing a data point cloud of a multi-line laser radar according to an exemplary embodiment of the present invention.

[0099] In the second aspect, if Figure 8 As shown, an exemplary embodiment of the present invention also provides a data point cloud processing method for a multi-line laser radar, which can be used for the multi-line laser radar described in the first aspect and its various embodiments above. The method may include: determining the round-trip time T of the laser between the target and the laser radar (S100); determining a first angle α between the laser and a predetermined plane in a predetermined coordinate system (S200); determining a rotation angle β of the laser emitter as the base rotates (S300); and determining the orientation of the target based on the round-trip time T, the position of the laser emitter in the predetermined coordinate system, the first angle α and the rotation angle β (S400).

[0100] The following combination Figure 7 The three-dimensional coordinate system shown and Figure 8 The method of this exemplary embodiment is further described.

[0101] Specifically, the round trip time T mentioned above can refer to the time from the laser emitter of the multi-line laser radar emitting the outgoing laser to the laser detector receiving the reflected laser. Figure 7 As shown, the predetermined coordinate system can be a three-dimensional rectangular coordinate system with the rotation axis of the laser radar as the z-axis. The origin O of the three-dimensional rectangular coordinate system can be selected by those skilled in the art as needed. Specifically, when the rotation axis of the multi-line laser radar is used as the z-axis of the three-dimensional rectangular coordinate system, the position of the xOy plane of the three-dimensional rectangular coordinate system can be set according to the time application scenario.

[0102] For example, in an application scenario, when the multi-line laser radar is arranged vertically on the roof of a vehicle, the rotation axis of the multi-line laser radar extends in the vertical direction, so the z-axis of the above-mentioned three-dimensional rectangular coordinate system also extends in the vertical direction. In this way, the xOy plane of the three-dimensional rectangular coordinate system can be selected on the upper surface of the rotating base of the laser radar, or on the surface of the road on which the vehicle travels. This can be set according to actual needs.

[0103] Furthermore, if Figure 7As shown, the first angle α mentioned above can refer to: the emission angle of the laser transmitter of the multi-line laser radar, that is, the angle between the outgoing laser emitted by the laser transmitter of the multi-line laser radar and the xOy plane of the three-dimensional rectangular coordinate system. Figure 7 As shown, the above-mentioned rotation angle β can refer to: when the laser emitter of the multi-line laser radar emits the outgoing laser, as the rotating base of the laser radar rotates, it is equal to the angle between the projection of the outgoing laser emitted by the laser emitter of the laser radar on the xOy plane and the x-axis.

[0104] In an actual application scenario, the round-trip time T can be determined by a timing unit connected to the laser detector. Specifically, the timing unit can record the time when the laser transmitter of the laser radar emits the outgoing laser and the time when the laser detector receives the reflected laser, and calculate the difference between the time when the laser detector receives the reflected laser and the time when the laser transmitter of the laser radar emits the outgoing laser, so as to obtain the round-trip time T.

[0105] Furthermore, in an exemplary embodiment, the emission angle of each laser emitter can be obtained by configuring the laser radar, thereby obtaining a first angle α between the laser light and the first plane in the predetermined coordinate system. It will be appreciated that since the emission angle of the laser emitter can be adjusted as needed, the first angle α between the laser light and the first plane in the predetermined coordinate system can also be adjustable or fixed.

[0106] Furthermore, in an exemplary embodiment, the rotation angle β of the laser emitter along the rotating base can be obtained based on the rotation speed of the rotating base of the laser radar. For example, the rotation angle β can be calculated using the following formula: β = w × t, where w is the angular velocity of the rotating base and t is the running time.

[0107] Furthermore, in an exemplary embodiment, the three-dimensional coordinates (x, y, z) of each pixel point on the detection target in the above predetermined coordinate system can be calculated using the following formula:

[0108]

[0109] Where h is the distance between the laser emitter and the xOy plane; l x is the distance between the laser emitter and the xOz plane; l y is the distance between the laser emitter and the yOz plane; c is the speed of the laser.

[0110] Furthermore, in an exemplary embodiment, the three-dimensional coordinates (x, y, z) of each pixel point of the lidar in the above-mentioned predetermined coordinate system can be calculated separately, and each pixel point can be drawn in the three-dimensional coordinates, so as to obtain a data point cloud of the detected target.

[0111] It will be appreciated that in this exemplary embodiment, the pixels generated by the multiple laser emitting and receiving modules of the laser radar can be calculated within the same predetermined coordinate system, and the data point cloud of the detected target can be drawn within the same predetermined coordinate system. Therefore, compared to traditional multi-line laser radars that model each laser emitting source as the center, the laser radar of the present invention can significantly improve the detection accuracy of the laser radar.

[0112] In an exemplary embodiment, the round trip time may be the time difference between the laser transmitter emitting the outgoing laser and the laser detector receiving the reflected laser from the detection target.

[0113] With reference to the various exemplary embodiments described above, those skilled in the art will appreciate that the present invention has at least the following beneficial effects.

[0114] On the one hand, the laser radar of the exemplary embodiment of the present invention increases the number of pixels on the detected target by providing multiple laser transmitting and receiving modules, and by arranging the multiple laser emitters included in the multiple laser transmitting and receiving modules to have different emission angles, thereby significantly improving the resolution of the laser radar. In addition, the multi-line laser radar of the exemplary embodiment of the present invention increases the number of laser emitters by arranging the multiple laser emitters at different heights, thereby improving the resolution of the laser radar without increasing the overall height of the laser radar, thereby reducing the size of the laser radar.

[0115] Furthermore, the multi-line laser radar and its data point cloud processing method of the present invention establish a three-dimensional rectangular coordinate system with the laser radar's rotation axis as the z-axis. This allows the calculation of the pixels generated by the laser radar's multiple laser transmitting and receiving modules within the same predetermined coordinate system, and also allows the plotting of the data point cloud of the detected target within the same predetermined coordinate system. Therefore, the laser radar and the method for determining the orientation of a target using the laser radar of the present invention can further improve the detection accuracy of the laser radar.

[0116] In the foregoing description of this specification, unless otherwise expressly specified or limited, terms such as "fixed," "mounted," "connected," or "connected" should be understood broadly. For example, the term "connected" can refer to a fixed connection, a removable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediary; or the internal connection between two components or the interaction between two components. Therefore, unless otherwise expressly defined in this specification, those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0117] According to the above description of this specification, those skilled in the art may also understand that the terms used below, such as "up", "down", "front", "back", "left", "right", "length", "width", "thickness", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", "center", "longitudinal", "lateral", "clockwise" or "counterclockwise", etc., which indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the drawings of this specification, and are only for the purpose of facilitating the explanation of the scheme of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the devices or elements involved must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms cannot be understood or interpreted as limitations on the scheme of the present invention.

[0118] In addition, the terms "first" or "second" used in this specification to refer to numbers or ordinal numbers are used for descriptive purposes only and should not be understood as explicitly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this specification, "plurality" means at least two, such as two, three or more, etc., unless otherwise clearly specified.

[0119] Although this specification has shown and described a number of embodiments of the present invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will conceive of many modifications, changes, and alternatives without departing from the ideas and spirit of the present invention. It should be understood that in practicing the present invention, various alternatives to the embodiments of the present invention described herein may be employed. The appended claims are intended to define the scope of protection of the present invention and therefore cover modular compositions, equivalents, or alternatives within the scope of these claims.

Claims

1. A multi-line laser radar, comprising a rotatable rotating base and a plurality of laser transmitting and receiving modules arranged circumferentially on the rotating base, wherein the laser transmitting and receiving modules include: A laser emission array comprising a plurality of laser emitters arranged in an array, wherein the laser emitters are configured to emit outgoing laser light, and the outgoing laser light is reflected by a detection target to generate reflected laser light; and A laser detection array comprising a plurality of laser detectors arranged in an array, wherein the laser detectors are used to receive reflected laser light. Among them, between the multiple laser emission arrays included in the multiple laser emission and receiving modules, the multiple laser emitters arranged correspondingly along the circumferential direction have different emission angles respectively, wherein the emission angle refers to the angle between the outgoing laser emitted by the laser emitter and the first plane, and the first plane is a plane perpendicular to the rotation axis of the laser radar.

2. The multi-line laser radar according to claim 1, wherein: Between the multiple laser emitting arrays included in the multiple laser emitting and receiving modules, the multiple laser emitters correspondingly arranged along the circumferential direction have different heights.

3. The multi-line laser radar according to claim 1, wherein: The number of the laser detectors is the same as the number of the laser emitters, and the laser detectors respectively have angles and heights corresponding to the laser emitters.

4. The multi-line laser radar according to claim 1, wherein: All laser emitters have different emission angles.

5. The multi-line laser radar according to claim 1, wherein the laser transmitting and receiving module further comprises: An optical receiving structure, comprising a receiving lens, wherein the receiving lens is used to collect reflected laser light and allow the collected reflected laser light to be incident on a corresponding laser detector; and / or The optical emission structure includes an emission lens, which is arranged around the receiving lens and is used to collect the outgoing laser emitted by the laser emitter.

6. The multi-line laser radar according to claim 5, wherein: The optical emission structure includes at least four emitting lenses, and the optical receiving structure includes at least one receiving lens, wherein the at least four emitting lenses are arranged on one side of the receiving lens.

7. The multi-line laser radar according to claim 1, wherein: The plurality of laser transmitting and receiving modules include: a first laser transmitting and receiving module, a second laser transmitting and receiving module, a third laser transmitting and receiving module and a fourth laser transmitting and receiving module. Among them, the first laser transmitting and receiving module and the third laser transmitting and receiving module are centrally symmetrical structures, the second laser transmitting and receiving module and the fourth laser transmitting and receiving module are centrally symmetrical structures, the first laser transmitting and receiving module and the second laser transmitting and receiving module are axially symmetrical structures, and the third laser transmitting and receiving module and the fourth laser transmitting and receiving module are axially symmetrical structures.

8. The multi-line laser radar according to claim 1, wherein: The laser emission array further comprises an emission plate, on which a plurality of laser emitters arranged in an array are disposed, and The laser detection array further includes a receiving plate, and a plurality of laser detectors arranged in an array are provided on the receiving plate.

9. The multi-line laser radar according to claim 1, wherein: The laser emitting array further comprises a light source driving device and at least four laser emitters electrically connected to the light source driving device; The laser detection array further includes a signal processing device and at least four laser detectors electrically connected to the signal processing device; and the laser detectors correspond to the laser emitters one by one.

10. The multi-line laser radar according to claim 1, wherein: The laser radar further includes a motor, a top plate and a light shield. The motor is connected to the rotating base so that the rotating base rotates under the drive of the motor; The top plate is arranged above the laser transmitting and receiving module; and The light blocking plate is disposed between the plurality of laser emitting and receiving modules to separate the plurality of laser emitting and receiving modules.

11. A method for processing data point clouds for a multi-line laser radar according to any one of claims 1 to 10, the method comprising: Determine the round trip time T of the laser between the target and the laser radar; Determining a first angle α between the laser and the predetermined plane in a predetermined coordinate system; determining a rotation angle β of the laser emitter along the rotating base; as well as The orientation of the target is determined according to the round-trip time T, the position of the laser transmitter in the predetermined coordinate system, the first angle α and the rotation angle β.

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