Lidar time delay correction method and device, electronic equipment and storage medium

Abstract

The present disclosure provides a laser radar time delay correction method and device, electronic equipment and storage medium, relating to the technical field of laser radar, and the method comprises: acquiring a first distance between a marker and a laser radar, the center of the marker, the centroid of the point cloud of a first module of the laser radar and the optical center of the laser radar are on the same straight line, the point cloud of the first module comprises N initial points, N is an integer greater than 1; acquiring the second distance of the N initial points, the second distance is the distance between the initial point and the optical center of the laser radar; determining a first target point in the N initial points, the absolute value of the difference between the second distance of the first target point and the first distance is less than a set distance threshold; based on the second distance and the first distance of the first target point, the corrected time delay corresponding to the first module is calculated; and the first module is corrected in time based on the corrected time delay corresponding to the first module. The present disclosure can reduce the measurement error of the laser radar.

Description

Technical Field

[0001] This disclosure relates to the field of lidar technology, specifically to a lidar delay correction method, apparatus, electronic device, and storage medium. Background Technology

[0002] A lidar (Light Detection and Ranging) system is a device that determines the distance to a target by sending pulse signals to it and then collecting the echo signals. In related technologies, the lidar's transmitting module emits pulse signals, and the receiving module acquires the pulse signals reflected from the object. The distance to the object is measured based on the time difference between the transmitted and received pulse signals. However, in these technologies, the transmitting or receiving modules of the lidar may have measurement delays, leading to significant errors in the distance calculation based on the time difference between the transmitted and received pulse signals.

[0003] It is evident that the relevant technologies suffer from measurement delays in the transmitting or receiving modules of lidar, resulting in significant errors in the calculated distance to objects. Summary of the Invention

[0004] This disclosure provides a method, apparatus, electronic device, and storage medium for correcting delays in lidar, in order to solve the problem in related technologies where the transmitting or receiving module of lidar has a measurement delay, resulting in a large error in the calculated distance to the object.

[0005] To solve the above problems, this disclosure is implemented as follows:

[0006] In a first aspect, embodiments of this disclosure provide a lidar delay correction method, including:

[0007] Obtain the first distance between the marker and the lidar, wherein the center of the marker, the centroid of the point cloud of the first module of the lidar, and the optical center of the lidar are on the same straight line, and the point cloud of the first module includes N initial points, where N is an integer greater than 1;

[0008] Obtain the second distance between the N initial points, where the second distance is the distance between the initial point and the optical center of the lidar;

[0009] Determine a first target point among the N initial points, wherein the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold;

[0010] Based on the second distance and the first distance of the first target point, the corrected delay corresponding to the first module is calculated;

[0011] The delay of the first module is corrected based on the corrected delay corresponding to the first module.

[0012] Secondly, embodiments of this disclosure also provide a lidar delay correction device, comprising:

[0013] The first acquisition module is used to acquire the first distance between the marker and the lidar. The center of the marker, the centroid of the point cloud of the first module of the lidar and the optical center of the lidar are on the same straight line. The point cloud of the first module includes N initial points, where N is an integer greater than 1.

[0014] The second acquisition module is used to acquire the second distance of the N initial points, wherein the second distance is the distance between the initial point and the optical center of the lidar;

[0015] The determination module is used to determine a first target point among the N initial points, wherein the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold.

[0016] The first calculation module is used to calculate the corrected time delay corresponding to the first module based on the second distance and the first distance of the first target point;

[0017] The correction module is used to correct the delay of the first module based on the correction delay corresponding to the first module.

[0018] Thirdly, embodiments of this disclosure also provide an electronic device, including a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps in the lidar delay correction method described in the first aspect above.

[0019] Fourthly, embodiments of this disclosure also provide a readable storage medium for storing a program that, when executed by a processor, implements the steps in the lidar delay correction method described in the first aspect above.

[0020] Fifthly, embodiments of this disclosure also provide a computer program product, including computer instructions, which, when executed by a processor, implement the steps of the lidar delay correction method as described in the first aspect above.

[0021] In this embodiment, when the center of the marker, the centroid of the point cloud of the first module of the lidar, and the optical center of the lidar are on the same straight line, the following steps are taken: First distance between the marker and the lidar is obtained; second distances between N initial points are obtained, where the second distance is the distance between the initial point and the optical center of the lidar; a first target point is determined among the N initial points, and the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold; based on the second distance and the first distance of the first target point, the corrected time delay corresponding to the first module is calculated; and the time delay of the first module is corrected based on the corrected time delay. Thus, when the center of the marker, the centroid of the point cloud of the first module, and the optical center of the lidar are on the same straight line, the second distance between the optical center measured by the first module and the point cloud of the first module is corrected using the first distance, thereby obtaining the corrected time delay of the first module. Then, the time delay of the first module is corrected based on the corrected time delay, achieving time delay correction for the transmitting or receiving module of the lidar, thereby reducing the measurement distance error of the lidar. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments of this disclosure will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A schematic diagram of the composition of a lidar system according to an embodiment of the present disclosure is shown;

[0024] Figure 2a An example of laser emission point distribution is shown when a lidar system according to an embodiment of the present disclosure performs field-of-view scanning;

[0025] Figure 2b An example of the receiving field of view of a lidar system according to an embodiment of the present disclosure is shown;

[0026] Figure 2c An example of the structure of an optical receiver in a lidar system according to an embodiment of the present disclosure is shown;

[0027] Figure 2d An example of the correspondence between the laser emission point and the receiving field of view of a lidar system according to an embodiment of the present disclosure is shown;

[0028] Figure 3 A flowchart illustrating a lidar delay correction method according to an embodiment of the present disclosure is shown;

[0029] Figure 4A schematic diagram showing the distribution of the first target points according to an embodiment of the present disclosure is provided.

[0030] Figure 5 A schematic diagram showing a lidar scanning marker and a plane according to an embodiment of the present disclosure;

[0031] Figure 6 One of the point cloud distribution diagrams of different modules according to embodiments of the present disclosure is shown;

[0032] Figure 7 A second schematic diagram showing the point cloud distribution of different modules according to an embodiment of the present disclosure is provided.

[0033] Figure 8 A schematic diagram of a first point cloud plane and a second point cloud plane according to an embodiment of the present disclosure is shown;

[0034] Figure 9 A schematic diagram illustrating a lidar delay correction process according to an embodiment of the present disclosure is shown.

[0035] Figure 10 A structural diagram of a lidar delay correction device according to an embodiment of the present disclosure is shown;

[0036] Figure 11 A schematic diagram of a vehicle integrating a lidar system according to an embodiment of the present disclosure is shown.

[0037] Figure 12 A block diagram illustrating the configuration of an electronic device according to an embodiment of the present disclosure is shown. Detailed Implementation

[0038] The following detailed description is based on the accompanying drawings and provides various exemplary embodiments of the present disclosure to aid in a comprehensive understanding. Various details are included in the following description to aid understanding; however, these details are considered exemplary only and not intended to limit the present disclosure, which is defined by the appended claims and their equivalents. The words and phrases used in the following description are intended only to provide a clear and consistent understanding of the present disclosure. Additionally, descriptions of well-known structures, functions, and configurations may have been omitted for clarity and brevity. Those skilled in the art will recognize that various changes and modifications can be made to the examples described herein without departing from the scope of the present disclosure.

[0039] Figure 1An exemplary lidar system 100 is shown, which can be applied to the techniques disclosed herein. The lidar system 100 may include a light emitter 101, a light receiver 106, and a controller 108. The light emitter 101 includes a light source 102 and a scanner 104. The light source 102 emits an emitted beam for scanning a target object 120. The light source 102 may be a laser, such as a solid-state laser (e.g., an edge-emitting laser (EEL) or a vertical-cavity surface-emitting laser (VCSEL) or an external-cavity semiconductor laser (ECDL)), a laser diode, or a fiber laser. The light source 102 may also include a light-emitting diode (LED). The light source 102 may emit different forms of light beams, including time-of-flight (TOF), continuous wave (CW), and quasi-continuous light. The operating wavelength of the light source can be 650nm to 1150nm, 800nm ​​to 1000nm, 850nm to 950nm, or 1300nm to 1600nm. In one or more embodiments, the light source 102 may further include optical components optically coupled to the light source 102 for collimating or focusing the light beam emitted by the light source 102. In one or more embodiments, the light source 102 includes at least one fiber laser. Each emitted light beam from the light source 102 can be continuous light lasting for a certain period of time, or it can be one or more light pulses.

[0040] Scanner 104 is used to deflect the direction of the emitted beam from light source 102 to scan target object 120, achieving a wider emission field of view or scanning field of view. Scanner 104 can be any number of optical mirrors driven by any number of drivers. For example, scanner 104 may include plane mirrors, prisms, mechanical galvanometers, polarization gratings, optical phased arrays (OPA), and microelectromechanical system (MEMS) galvanometers. For MEMS galvanometers, the mirror surface rotates or translates in one or two dimensions under electrostatic / piezoelectric / electromagnetic actuation. Driven by the drivers, scanner 104 guides the beam from the light source to various positions within the field of view to scan target object 120 within the field of view.

[0041] After the light beam is reflected from the target object 120, a portion of the reflected light returns to the lidar system 100 and is received by the optical receiver 106. The optical receiver 106 receives and detects a portion of the reflected light from the target object 120 and generates a corresponding electrical signal. The optical receiver may include a receiving unit and associated receiving circuitry. Each receiving circuitry can be used to process the output electrical signal of the corresponding receiving unit. The receiving unit includes various forms of photodetectors or one-dimensional or two-dimensional arrays of photodetectors; correspondingly, the receiving circuitry may be a single circuit or an array of multiple circuits. The photodetector measures the power, phase, or time characteristics of the reflected light and generates a corresponding current output. The photodetector may be an avalanche photodiode (APD), a single-photon avalanche photodiode (SPAD), a PN-type photodiode, or a PIN-type photodiode.

[0042] Controller 108 is communicatively coupled to one or more of the light source 102, scanner 104, and light receiver 106. Controller 108 can control whether and when the light source 102 emits a light beam. Controller 108 can control the scanner 104 to scan the light beam to a specific location. Controller 108 can process and analyze the electrical signals output by the light receiver to ultimately determine the position, velocity, and other characteristics of the target object 120. Controller 108 may include an integrated circuit (IC), an application-specific integrated circuit (ASIC), a microchip, a microcontroller, a central processing unit, a graphics processing unit (GPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), or other circuits suitable for executing instructions or implementing logical operations. Instructions executed by controller 108 can be preloaded into an integrated or separate memory (not shown). The memory can store configuration data or commands for the light source 102, scanner 104, or light receiver 106. The memory can also store electrical signals output from the optical receiver 106 or analysis results based on the output electrical signals. For example, the memory can store relevant information about stray light signals detected during the calibration period for use in subsequent working periods. The memory may include random access memory (RAM), read-only memory (ROM), hard disk, optical disk, magnetic disk, flash memory, or other volatile or non-volatile memory. The controller 108 may include one or more processing circuits. In the case of multiple processing circuits, the processing circuits may have the same or different structures and interact or cooperate with each other through electrical, magnetic, optical, acoustic, mechanical, or other means.

[0043] In one or more embodiments, the lidar system 100 may further include a emitting lens 110. The emitting lens 110 can be used to expand a light beam emitted by the light source 102 and directed by the scanner 104. The emitting lens 110 may include diffractive optical elements (DOEs) for shaping, separating, or diffusing the light beam. The emitting lens 110 may be present independently or integrated into other components (e.g., the scanner 104 or the light source 102). The position of the emitting lens 110 in the emission optical path from the light source to the target object is not limited to... Figure 1As shown in the diagram, the position can be changed to another location. For example, the emitting lens can be arranged between the light source 102 and the scanner 104, so that the beam emitted by the light source 102 is first expanded by the emitting lens and then redirected by the scanner.

[0044] In one or more embodiments, the lidar system 100 may further include a receiving lens 112 and an aperture stop 113. The receiving lens 112 is located in front of the light receiver 106 on the receiving path of the emitted light from the target object 120 to the light receiver 106. The receiving lens 112 may include an imaging system lens such that the focal point of the reflected beam is in front of or behind the detection surface of the photodetector or photodetector array, or exactly above the detection surface. In some cases, instead of existing as a separate component, the receiving lens 112 may also be integrated into the light receiver 106. The aperture stop 113 is used to limit the angle of incident light onto the light receiver 106, block stray light, etc.

[0045] In one or more embodiments, the lidar system 100 may further include a housing 114 for enclosing one or more of the aforementioned components therein for protection. In some embodiments, the housing 114 is made of an opaque material, and transparent areas or windows 116 may be provided on the housing 114 to allow the emitted or reflected beam to pass through. In other embodiments, the housing 114 itself is made of a transparent material, thereby allowing the emitted or reflected beam to pass through from any location.

[0046] In some embodiments, the lidar system 100 may include a coaxial optical transceiver system. A coaxial optical transceiver system refers to a transmission path from the light source 102 to the target object 120 that at least partially overlaps with the reception path from the target object 120 to the optical receiver 106. For example, with... Figure 1 Unlike the previous method, the reflected beam can travel in the opposite direction through the scanner 104 to reach the optical receiver 106. For a coaxial optical transceiver system, not only does the exit angle of the emitted beam change with the deflection of the scanner, but the receiving angle of the light that the optical receiver can receive also changes synchronously with the deflection of the scanner. That is, the receiving field of view always remains equivalent to the scanning range of the emitted beam.

[0047] In other embodiments, the lidar system 100 may include a non-coaxial optical transceiver system. A non-coaxial optical transceiver system refers to a system where the transmission path from the light source 102 to the target object 120 does not overlap with the reception path from the target object 120 to the optical receiver 106. For example, as... Figure 1 As shown, the reflected beam does not reach the optical receiver 106 via the scanner 104. For a non-coaxial optical transceiver system, although the exit angle of the emitted beam changes with the deflection of the scanner, the total receiving field of view of the optical receiver is fixed and does not change with the deflection of the scanner.

[0048] A lidar system can control a scanner to guide the emitted beam according to a predetermined scanning pattern. Typically, the scanner presents a closed scanning pattern in space and repeats the scan periodically. Common scanning patterns include row and column grating, Lissajous figures, and spiral patterns. Figure 2a This diagram illustrates an example of a laser point cloud when a lidar system scans according to a row-and-column raster scanning pattern. Each pixel 204 in the point cloud represents the position where the scanner guides the emitted beam into the emission field of view (or scanning field of view). The collection of all pixels 204 constitutes the emission field of view 202 of the lidar system. Depending on the predetermined scanning pattern, the emission field of view 202 can have various shapes, and is not limited to these. Figure 2a The rectangular shape shown. Each pixel 204 can be associated with one or more emitted beams or one or more measurements.

[0049] Figure 2b An example of the receiving field of view distribution of a lidar system including a non-coaxial optical transceiver system is shown. In this example, the optical receiver of the lidar system consists of multiple receiving submodules, each including one or more receiving units and their corresponding receiving circuitry. Each receiving submodule is capable of receiving reflected light within a relatively small range. For example, Figure 2b Each rectangle in the diagram represents the range of reflected light that a corresponding receiving submodule of the lidar system can receive, also known as the receiving field of view of the corresponding receiving submodule. The collection of the receiving fields of view of all receiving submodules constitutes the total receiving field of view 206 of the optical receiver.

[0050] Figure 2c It shows how to provide Figure 2b A schematic diagram of the optical receiver of a receiving field-of-view lidar system. The optical receiver includes one or more receiving units 210 and corresponding one or more receiving circuits 214. The receiving unit 210 is connected to the corresponding receiving circuit 214 via an electrical connector 212. For example, Figure 2b The receiving field of view 208 in the middle corresponds to Figure 2c The receiving submodule consists of receiving unit 216 and corresponding receiving circuit 214.

[0051] Figure 2d It shows having Figure 2a Scanning laser point cloud and Figure 2b This is an example of the correspondence between laser emission and the receiving field of view in a lidar system during normal operation. During normal operation, as the scanner deflects, the emitted beam is directed to different positions within the emission field of view. The controller instructs the receiving submodule in the light receiver corresponding to that position to activate, thereby receiving the reflected beam and completing the measurement. For example, pixel 218 could correspond to... Figure 2aPixel 204 in the image, the receiving field of view 220 can correspond to Figure 2b The receiving field of view 208 is used. When the lidar system generates an emitted beam pointing to pixel 218, the receiving submodule corresponding to the receiving field of view 220 needs to be turned on, i.e., it can be turned on. Figure 2c The receiver includes a receiving submodule comprising a receiving unit 216 and a receiving circuit 214. All receiving submodules in the optical receiver, except those corresponding to the receiving field of view 220, can be turned off or put into sleep mode.

[0052] It should be recognized that, Figures 2a to 2d The illustrated transmit field of view, receive field of view, and corresponding receive submodule distribution are merely schematic. The lidar system according to this disclosure may have different scanning patterns, transmit field of view, receive field of view distributions, shapes, numbers, and distributions of receive submodules, as well as different correspondences between the transmit and receive fields of view.

[0053] In related technologies, an FPGA generates drive signals to control the LiDAR's transmitting module to emit pulse signals. The LiDAR's receiving module acquires the pulse signals reflected by the object, and the distance to the object is measured based on the time difference between the emitted and received pulse signals. During the measurement process, the LiDAR's transmitting or receiving modules may experience measurement delays, leading to errors based on the time difference between the emitted and received pulse signals. Nanosecond-level measurement delays can cause centimeter-level errors in the ranging results; therefore, correction of the absolute delay parameter is necessary to improve the accuracy of the ranging measurement.

[0054] To increase the horizontal and vertical width of a lidar's field of view, multiple transmitting modules (usually containing lasers) are typically introduced at the transmitting end. Alternatively, a single transmitting module may use beam splitter technology to separate multiple laser beams. Each laser or independent beam forms a separate field of view, and the complete field of view of a lidar is often formed by stitching together multiple fields of view created by multiple lasers or beams. Similarly, the receiving end also has multiple receiving modules to receive the pulse signals from multiple lasers or beams reflected by an object.

[0055] It should be noted that different transmitting modules have different transmission delays, different receiving modules have different receiving delays, and the beam splitter has different transmission media after beam splitting, resulting in different transmission delays for each field of view. Therefore, it is necessary to correct the delay of each transmitting module and / or receiving module, that is, to correct the delay of each field of view, in order to ensure the accuracy of ranging.

[0056] For details, please see Figure 3 , Figure 3 This is a flowchart of a lidar delay correction method according to an embodiment of this disclosure, as shown below. Figure 3 As shown, the lidar delay correction method includes:

[0057] Step 301: Obtain the first distance between the marker and the lidar. The center of the marker, the centroid of the point cloud of the first module of the lidar, and the optical center of the lidar are on the same straight line. The point cloud of the first module includes N initial points, where N is an integer greater than 1.

[0058] Step 302: Obtain the second distance between the N initial points, where the second distance is the distance between the initial point and the optical center of the lidar;

[0059] Step 303: Determine the first target point among the N initial points, wherein the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold;

[0060] Step 304: Based on the second distance and the first distance of the first target point, calculate the corrected delay corresponding to the first module;

[0061] Step 305: Perform time delay correction on the first module based on the corrected time delay corresponding to the first module.

[0062] The aforementioned marker is pre-set at a location scannable by the lidar. The initial distance between the marker and the optical center of the lidar is determined through actual measurement to ensure its accuracy. The lidar's first module can be either a transmitting or receiving module, used to transmit and receive signal pulses. The point cloud formed by scanning the marker by the first module is the point cloud of the first module. Specifically, the first distance is the distance between the center of the marker and the optical center of the lidar. Optionally, the marker can be a Lambertian plate.

[0063] The aforementioned second distance is the distance between each of the N initial points in the point cloud of the first module and the optical center of the lidar. The aforementioned distance threshold is used to filter out the first target point from the N initial points. The second distance of the first target point can be greater than or less than the first distance. The first target point is filtered by the absolute value of the difference between the second distance and the first distance, ensuring that the first target point is a point in the point cloud of the first module that is close to the center of the marker, i.e., a point close to the centroid in the point cloud of the first module.

[0064] The center of the aforementioned marker, the centroid of the point cloud of the first module, and the optical center of the lidar are all on the same straight line. The second distance between the first module and its point cloud is corrected by using a first distance, thereby correcting the time delay of the first module. It should be noted that when the first module has no time delay, the distance between the first module and its point cloud is the same as the first distance. However, when the first module has a time delay, the distance between the first module and its point cloud deviates from the first distance. This deviance is used to determine the time delay of the first module.

[0065] Specifically, the second distance between the point cloud of the first module and the optical center of the lidar is collected. A first target point is selected from N initial points in the point cloud of the first module. The absolute value of the difference between the second distance and the first distance of the first target point is less than a set threshold. That is, the first target point is a point distributed around the centroid of the point cloud. The time delay is then determined by the first distance and the second distance to correct the time delay of the first module.

[0066] In this embodiment, when the center of the marker, the centroid of the point cloud of the first module of the lidar, and the optical center of the lidar are on the same straight line, the following steps are taken: First distance between the marker and the lidar is obtained; second distances between N initial points are obtained, where the second distance is the distance between the initial point and the optical center of the lidar; a first target point is determined among the N initial points, and the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold; based on the second distance and the first distance of the first target point, the corrected time delay corresponding to the first module is calculated; and the time delay of the first module is corrected based on the corrected time delay. Thus, when the center of the marker, the centroid of the point cloud of the first module, and the optical center of the lidar are on the same straight line, the second distance between the optical center measured by the first module and the point cloud of the first module is corrected using the first distance, thereby obtaining the corrected time delay of the first module. Then, the time delay of the first module is corrected based on the corrected time delay, achieving time delay correction for the transmitting or receiving module of the lidar, thereby reducing the measurement distance error of the lidar.

[0067] Furthermore, after obtaining the second distance between the N initial points, the method further includes:

[0068] Obtain the azimuth and / or elevation angles of the N initial points relative to the optical center of the lidar;

[0069] The absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold, and the azimuth and / or elevation angle of the first target point relative to the optical center of the lidar meets preset conditions.

[0070] The preset conditions include at least one of the following:

[0071] The difference between the azimuth angle of the first target point relative to the optical center of the lidar and the azimuth angle of the adjacent initial point is less than a first set angle threshold.

[0072] The difference between the elevation angle of the first target point relative to the optical center of the lidar and the elevation angle of the adjacent initial point is less than a second set angle threshold.

[0073] It should be noted that, as Figure 4 As shown, the first target point selected from N initial points based on the first distance and a set distance threshold may be a free point that is far from the centroid of the point cloud of the first module. In this case, the correction delay is determined based on the second distance and the first distance of the first target point. The correction delay may be too large or too small, and it is necessary to further limit the range of the first target point to improve the accuracy of the correction delay.

[0074] Specifically, the range of the first target point is further defined by the azimuth and / or elevation angles of N initial points relative to the optical center of the lidar. Specifically, when the first target point meets a set distance threshold, the difference between the azimuth angle of the first target point relative to the optical center of the lidar and the azimuth angle of the adjacent initial point is less than a first set angle threshold, and / or, the difference between the elevation angle of the first target point relative to the optical center of the lidar and the elevation angle of the adjacent initial point is less than a second set angle threshold. Thus, when the difference between the azimuth angle of the first target point relative to the optical center of the lidar and the azimuth angle of the adjacent initial point is less than the first set angle threshold, multiple first target points are continuously distributed horizontally around the centroid; and when the difference between the elevation angle of the first target point relative to the optical center of the lidar and the elevation angle of the adjacent initial point is less than the second set angle threshold, multiple first target points are continuously distributed vertically around the centroid. This avoids the first target point being a distant, isolated point far from the centroid of the point cloud of the first module, improving the accuracy of delay correction.

[0075] Furthermore, by using both azimuth and elevation angles to define the range of the first target point, multiple first target points are confined to a specific area. Figure 4 The centroid of the point cloud of the first module is also within the dashed box shown, so the corrected time delay can be calculated by the second distance and the first distance of the first target point.

[0076] For example, first, screen the N initial points based on a set distance threshold to obtain a set D{1} that meets the set distance threshold: D1 - X < dx < D1 + X, where D1 is the first distance, dx is the set distance threshold, and X is the second distance of a point in the set D{1}; then, screen the points in the set D{1} based on a first set angle threshold and a second set angle threshold to obtain a first target point. The first target point is a point in the set D{2}, and the points in the set D{2} satisfy D{2} = [(|a x –a x-1 |<Δa)&(|e x –e x-1 |<Δe)], where Δa is the first set angle threshold, Δe is the second set angle threshold, a x is the azimuth angle of point x relative to the optical center of the lidar, a x-1 is the azimuth angle of point x - 1 relative to the optical center of the lidar, e x is the elevation angle of point x relative to the optical center of the lidar, e x-1 is the elevation angle of point x - 1 relative to the optical center of the lidar, and points x and x - 1 are adjacent.

[0077] In an embodiment of the present disclosure, by obtaining the azimuth angle and / or elevation angle of the N initial points relative to the optical center of the lidar; the absolute value of the difference between the second distance and the first distance of the first target point is less than the set distance threshold, and the azimuth angle and / or elevation angle of the first target point relative to the optical center of the lidar meet the preset conditions. Among them, the preset conditions include at least one of the following: the difference between the azimuth angle of the first target point relative to the optical center of the lidar and the azimuth angle of an adjacent initial point is less than the first set angle threshold; the difference between the elevation angle of the first target point relative to the optical center of the lidar and the elevation angle of an adjacent initial point is less than the second set angle threshold. In this way, the range of the first target point is further limited by the azimuth angle and / or elevation angle of the N initial points relative to the optical center of the lidar, thereby avoiding the first target point being a stray point far from the centroid of the point cloud of the first module and improving the accuracy of the correction delay.

[0078] In one embodiment, calculating the correction delay corresponding to the first module based on the second distance and the first distance of the first target point includes at least one of the following:

[0079] When the first target point is one of the N initial points, calculate the first difference between the second distance and the first distance of the first target point, and set the quotient of the first difference and twice the speed of light as the correction delay corresponding to the first module;

[0080] When the first target point is one of the N initial points, the average value of the second distances of the multiple initial points and the second difference of the first distance are calculated, and the quotient of the second difference and twice the speed of light is set as the correction delay corresponding to the first module.

[0081] It should be noted that the first target point can be one initial point or multiple initial points. When the first target point is one initial point, this initial point is the one closest to the centroid of the point cloud of the first module, and the corrected time delay can be calculated based on the second distance from this initial point. When the first target point is multiple initial points, these multiple initial points can be evenly distributed around the centroid of the point cloud of the first module (e.g., ...). Figure 4 As shown in the figure, the corrected time delay can be calculated based on the average of the second distances from multiple initial points.

[0082] Specifically, when the first target point is one of N initial points, the second distance to the first target point and the first difference between the first distance are calculated, and the quotient of the first difference and twice the speed of light is set as the correction delay corresponding to the first module.

[0083] When the first target point is multiple initial points among N initial points, calculate the average of the second distances of the multiple initial points and the second difference of the first distance, and set the quotient of the second difference and twice the speed of light as the correction delay corresponding to the first module.

[0084] The calculation process can be represented by the following formula:

[0085]

[0086] t0 is the corrected time delay, ΔD is the first or second difference, and V0 is the speed of light.

[0087] In one embodiment, after calculating the corrected delay corresponding to the first module based on the second distance and the first distance from the first target point, the method further includes:

[0088] A first point cloud plane formed by the point cloud of the first module and a second point cloud plane formed by the point cloud of the second module of the lidar are obtained. The second module is adjacent to the first module. Both the second module and the first module are transmitting modules or receiving modules of the lidar. The second point cloud plane is less than or equal to the first point cloud plane.

[0089] Calculate the third distance between the second point cloud plane and the first point cloud plane;

[0090] Calculate the first relative time delay, which is the quotient of the third distance and twice the speed of light;

[0091] The sum of the first relative delay and the corrected delay corresponding to the first module is set as the corrected delay of the second module.

[0092] It should be noted that when using markers to correct the delay of the transmitting or receiving modules, the overall point cloud scanned by the lidar is large. Due to the size limitation of the markers, different transmitting or receiving modules cannot directly scan the markers to form a point cloud, making it impossible to directly correct each transmitting or receiving module using the markers. The position of the lidar needs to be adjusted, which results in a long correction time for each transmitting or receiving module within the lidar. In this embodiment, the delay of the first module, which has already been calculated, is used to correct the delay of other modules. The distance between the marker and the first module is only used when calculating the corrected delay of the first module. When calculating the corrected delay of the second module, it is not necessary to measure the distance between the second module and the marker, thus improving the correction efficiency.

[0093] Specifically, the first point cloud plane and the second point cloud plane mentioned above are the planes containing the point clouds obtained by the first module and the second module scanning the same plane. For example... Figure 5 As shown, the first module first scans the markers to calculate its corrected time delay. Then, the first and second modules scan the same plane to obtain a first point cloud plane and a second point cloud plane. Since the first and second point cloud planes are point cloud planes formed by scanning the same plane, the relative time delay between the first and second point cloud planes can be calculated from the distance between them. Combined with the corrected time delay of the first module, the corrected time delay of the second module can be determined.

[0094] In one embodiment, the second point cloud plane includes a plurality of points, and calculating the third distance between the second point cloud plane and the first point cloud plane includes:

[0095] By performing surface fitting on the multiple points, the surface equation corresponding to the cloud plane of the second point is obtained;

[0096] Calculate the equation of the straight line corresponding to at least one second target point, wherein the at least one second target point and the optical center of the lidar are located on a straight line, and the at least one second target point is a point in the first point cloud plane;

[0097] Based on the corresponding straight line equation and the surface equation, the intersection point corresponding to the at least one second target point is calculated, and the intersection point is located in the second point cloud plane;

[0098] The average distance between the at least one second target point and its corresponding intersection point is set as the third distance.

[0099] It should be noted that the differences in signal transmission between the multiple channels within the transmitting and receiving modules can lead to slight differences in actual ranging, causing the point cloud formed by the transmitting module to be a slightly curved surface. Therefore, in this embodiment, a surface fitting method is used to obtain the surface equation corresponding to the second point cloud plane, thereby improving the accuracy of calculating the third distance.

[0100] The above calculation of the straight line equation corresponding to at least one second target point is as follows: Figure 8 As shown: Determine the coordinates P1(x1,y1,z1) of the second target point P1 in the first point cloud plane; calculate the unit vector V_P1(m,n,p) of the straight line connecting the second target point P1 and the optical center of the lidar, and obtain the parametric equation of the straight line passing through point P1 from the unit vector V_P1:

[0101]

[0102] The surface equation corresponding to the second point cloud plane is: a×X 2 +b×XY+c×Y 2 +d×X+e×Y+fZ=0, by combining the linear parametric equation and the surface equation, we can obtain the intersection point P0(x0,y0,z0), and then calculate the third distance △d between P0(x0,y0,z0) and P1(x1,y1,z1).

[0103] In this embodiment, a surface equation corresponding to the second point cloud plane is obtained by performing surface fitting on multiple points; a straight line equation corresponding to at least one second target point is calculated, wherein at least one second target point and the optical center of the lidar are located on a straight line, and at least one second target point is a point among N initial points; based on the corresponding straight line equation and surface equation, the intersection point corresponding to at least one second target point is calculated; the average distance between at least one second target point and the corresponding intersection point is set as the third distance, so as to determine the relative time delay of the second module through the third distance.

[0104] Furthermore, both the first module and the second module are either transmitting or receiving modules, and the point clouds formed by the first module and the second module during simultaneous scanning are adjacent, such as... Figure 6 As shown, the time delay of each module is corrected in this way to complete the time delay correction of all transmitting and receiving modules in the lidar.

[0105] Furthermore, the second point cloud plane is smaller than or equal to the first point cloud plane to improve the accuracy of the calculated third distance between the first and second point cloud planes. Since the third distance is the average distance between at least one second target point and its corresponding intersection point, the more intersection points with the second point cloud plane, the higher the accuracy of the calculated third distance between the first and second point cloud planes. If the first point cloud plane is small, some areas in the second point cloud plane may not have intersection points, resulting in lower accuracy. Therefore, in this embodiment, the second point cloud plane is smaller than or equal to the first point cloud plane, ensuring that all positions in the second point cloud plane can be intersection points, further improving the accuracy of the calculated third distance.

[0106] It should be noted that the areas of the point clouds scanned by adjacent modules can be different, such as... Figure 7 As shown, the point cloud area corresponding to the eighth module is larger than that corresponding to the second module. Therefore, it is necessary to correct the point cloud of the eighth module by using the point clouds corresponding to the second and fourth modules to obtain the corrected time delay of the eighth module relative to the second module.

[0107] In this embodiment, a first point cloud plane is formed by the point cloud of the first module, and a second point cloud plane is formed by the point cloud of the second module of the lidar. The second module is adjacent to the first module, and both the second and first modules are transmitting or receiving modules of the lidar. The second point cloud plane is less than or equal to the first point cloud plane. A third distance between the second and first point cloud planes is calculated. A first relative time delay is calculated, which is the quotient of the third distance and twice the speed of light. The sum of the first relative time delay and the correction time delay corresponding to the first module is set as the correction time delay of the second module. In this way, the relative time delay between the second and first modules is calculated by the third distance between the first and second point cloud planes, and the correction time delay of the second module is calculated by combining it with the correction time delay of the first module. The distance between the first and second point cloud planes is directly calculated, eliminating the need to first determine the distance between the first module and the marker using a marker, or to determine the distance between the second module and the marker using a marker. This reduces measurement steps and improves correction efficiency.

[0108] Furthermore, the corrected delays of other modules can be determined directly by the first module whose corrected delay is obtained through the marker, or the corrected delays of other modules can be determined by the module whose corrected delay is obtained through the relative delay. Specifically, after setting the sum of the first relative delay and the corrected delay corresponding to the first module as the corrected delay of the second module, the method further includes:

[0109] The third point cloud plane is formed by the point cloud of the third module of the lidar. The third module is also adjacent to the second module. Both the third module and the second module are the transmitting module or receiving module of the lidar. The third point cloud plane is smaller than or equal to the second point cloud plane.

[0110] Calculate the fourth distance between the third point cloud plane and the second point cloud plane;

[0111] Calculate the second relative time delay, which is the quotient of the fourth distance and twice the speed of light;

[0112] The quotient of the fourth distance and twice the speed of light is set as the second relative delay, and the sum of the second relative delay and the corrected delay corresponding to the second module is set as the corrected delay of the third module.

[0113] In this way, the correction delay of the third module is determined by the correction delay of the second module. The second module is the module whose correction delay is determined by the first relative delay. This allows other modules that have not been corrected to correct their delays by obtaining the correction delay from the first module through the marker, or by obtaining the correction delay from the module through the relative delay.

[0114] Furthermore, such as Figure 9 As shown, in the process of time delay correction for different modules of the lidar, the correction time delay of one module is determined first, and then the time delays of each transmitting module and each receiving module are corrected sequentially until the time delay correction of all modules is completed. After the correction is completed, a self-test is performed on each transmitting module and each receiving module to determine the accuracy of the ranging. For example, each transmitting module scans the same plane to determine whether the distance results obtained by each transmitting module are the same. If they are the same or the error is less than a threshold, the correction of each transmitting module is confirmed to be complete. The self-test for each receiving module is the same as that for each transmitting module and will not be described again.

[0115] Please participate Figure 10 , Figure 10 This is a flowchart of a lidar delay correction device according to an embodiment of the present disclosure, as shown below. Figure 10 As shown, the lidar delay correction device 1000 includes:

[0116] The first acquisition module 1001 is used to acquire the first distance between the marker and the lidar. The center of the marker, the centroid of the point cloud of the first module of the lidar and the optical center of the lidar are on the same straight line. The point cloud of the first module includes N initial points, where N is an integer greater than 1.

[0117] The second acquisition module 1002 is used to acquire the second distance of the N initial points, wherein the second distance is the distance between the initial point and the optical center of the lidar;

[0118] The determining module 1003 is used to determine a first target point among the N initial points, wherein the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold.

[0119] The first calculation module 1004 is used to calculate the corrected time delay corresponding to the first module based on the second distance and the first distance of the first target point;

[0120] The correction module 1005 is used to correct the delay of the first module based on the correction delay corresponding to the first module.

[0121] In one embodiment, after the second acquisition module 1002, the lidar delay correction device 1000 further includes:

[0122] The third acquisition module is used to acquire the azimuth and / or elevation angles of the N initial points relative to the optical center of the lidar;

[0123] The absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold, and the azimuth and / or elevation angle of the first target point relative to the optical center of the lidar meets preset conditions.

[0124] The preset conditions include at least one of the following:

[0125] The difference between the azimuth angle of the first target point relative to the optical center of the lidar and the azimuth angle of the adjacent initial point is less than a first set angle threshold.

[0126] The difference between the elevation angle of the first target point relative to the optical center of the lidar and the elevation angle of the adjacent initial point is less than a second set angle threshold.

[0127] In one embodiment, after the first calculation module 1004, the lidar delay correction device 1000 further includes:

[0128] The fourth acquisition module is used to acquire the first point cloud plane formed by the point cloud of the first module and the second point cloud plane formed by the point cloud of the second module of the lidar. The second module is adjacent to the first module. Both the second module and the first module are the transmitting module or receiving module of the lidar. The second point cloud plane is less than or equal to the first point cloud plane.

[0129] The second calculation module is used to calculate the third distance between the second point cloud plane and the first point cloud plane;

[0130] The third calculation module is used to calculate the first relative time delay, which is the quotient of the third distance and twice the speed of light;

[0131] The fourth calculation module is used to set the sum of the first relative delay and the corrected delay corresponding to the first module as the corrected delay of the second module.

[0132] In one embodiment, the second point cloud plane includes multiple points, and the second calculation module includes:

[0133] A fitting unit is used to perform surface fitting on the plurality of points to obtain the surface equation corresponding to the cloud plane of the second point;

[0134] The first calculation unit is used to calculate the straight line equation corresponding to at least one second target point, wherein the at least one second target point and the optical center of the lidar are located on a straight line, and the at least one second target point is a point in the first point cloud plane;

[0135] The second calculation unit is used to calculate the intersection point corresponding to the at least one second target point based on the corresponding straight line equation and the surface equation.

[0136] The third calculation unit is used to set the average distance between the at least one second target point and the corresponding intersection point as the third distance.

[0137] In one embodiment, after the fourth calculation module, the lidar delay correction device 1000 further includes:

[0138] The fifth acquisition module is used to acquire the third point cloud plane formed by the point cloud of the third module of the lidar. The third module is also adjacent to the second module. Both the third module and the second module are the transmitting module or receiving module of the lidar. The third point cloud plane is less than or equal to the second point cloud plane.

[0139] The fifth calculation module is used to calculate the fourth distance between the third point cloud plane and the second point cloud plane;

[0140] The sixth calculation module is used to calculate the second relative time delay, which is the quotient of the fourth distance and twice the speed of light;

[0141] The seventh calculation module is used to set the quotient of the fourth distance and twice the speed of light as the second relative time delay, and to set the sum of the second relative time delay and the correction time delay corresponding to the second module as the correction time delay of the third module.

[0142] In one embodiment, the first computing module 1004 includes at least one of the following:

[0143] The fourth calculation unit is used to calculate the second distance of the first target point and the first difference of the first distance when the first target point is one of the N initial points, and to set the quotient of the first difference and twice the speed of light as the correction delay corresponding to the first module.

[0144] The fifth calculation unit is used to calculate the average value of the second distances of the multiple initial points and the second difference of the first distance when the first target point is multiple initial points among the N initial points, and to set the quotient of the second difference and twice the speed of light as the correction delay corresponding to the first module.

[0145] The lidar delay correction device provided in this disclosure is capable of implementing each process of the above-described lidar delay correction method, with one-to-one correspondence of technical features and achieving the same technical effect. To avoid repetition, it will not be described again here.

[0146] It should be noted that the lidar delay correction device in the embodiments of this disclosure can be a device, or it can be a component, integrated circuit, or chip in an electronic device.

[0147] Furthermore, Figure 11 A schematic diagram of a vehicle 1100 integrating a lidar system according to an embodiment of the present disclosure is shown. The vehicle 1100 may include at least a lidar system 1102, a vehicle controller 1104, and a motion system 1106. The lidar system 1102 can use... Figure 1 The lidar system 100 is implemented in the present disclosure. Accordingly, the light source 1112, scanner 1114, light receiver 1116, and controller 1118 correspond to the light source 102, scanner 104, light receiver 106, and controller 108 of the lidar system 100, respectively. The difference is that the vehicle controller 1104 can be communicatively coupled to the light source 1112, scanner 1114, and light receiver 1116 via the controller 1118. In other embodiments, the vehicle controller 1104 can also be directly communicatively coupled to the light source 1112, scanner 1114, and light receiver 1116. In some embodiments, the lidar system 1102 may not include the controller 1118. The technology for calibrating the lidar system according to embodiments of the present disclosure can be implemented independently by the vehicle controller 1104, or it can be implemented collaboratively by the vehicle controller 1104 and partly by the controller 1118. The motor system 1106 may include a power subsystem, a braking subsystem, and a steering subsystem, etc. The vehicle controller 1104 can adjust the mobility system 1106 based on the detection results of the lidar system 1102.

[0148] Figure 12A configuration block diagram of an electronic device 1200 according to an embodiment of the present disclosure is shown. The electronic device 1200 can be any type of general-purpose or special-purpose computing device, such as a desktop computer, laptop computer, server, mainframe computer, cloud-based computer, tablet computer, wearable device, vehicle electronics, etc. Figure 12 As shown, the electronic device 1200 includes an input / output (I / O) interface 1201, a network interface 1202, a memory 1204, and a processor 1203.

[0149] I / O interface 1201 is a collection of components that can receive input from a user and / or provide output to a user. I / O interface 1201 may include, but is not limited to, buttons, keyboards, keypads, liquid crystal displays (LCDs), LED displays, or other similar display devices, including display devices with touchscreen capabilities that enable interaction between a user and an electronic device.

[0150] Network interface 1202 may include various adapters and circuitry implemented in software and / or hardware to enable communication with the LiDAR system using wired or wireless protocols. Wired protocols include, for example, any one or more of serial, parallel, Ethernet, Universal Serial Bus (USB), or other wired communication protocols. Wireless protocols include, for example, any IEEE 802.11 Wireless Fidelity (Wi-Fi) protocol, cellular network communication protocols, etc.

[0151] Memory 1204 includes a single memory or one or more memories or storage locations, including but not limited to random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, logic blocks of an FPGA, hard disk, or any other layer of the memory hierarchy. Memory 1204 can be used to store any type of instructions, software, or algorithms, including instructions 1205 for controlling the general functions and operation of electronic device 1200.

[0152] Processor 1203 controls the general operation of electronic device 1200. Processor 1203 may include, but is not limited to, a CPU, hardware microprocessor, hardware processor, multi-core processor, single-core processor, microcontroller, application-specific integrated circuit (ASIC), DSP, or other similar processing device, capable of executing any type of instructions, algorithms, or software for controlling the operation and functions of electronic device 1200 according to embodiments described in this disclosure. Processor 1203 may be various implementations of digital circuit systems, analog circuit systems, or mixed-signal (analog and digital combination) circuit systems that perform functions in a computing system. Processor 1203 may include, for example, portions or circuitry of an integrated circuit (IC), a single processor core, an entire processor core, a single processor, programmable hardware devices such as a field-programmable gate array (FPGA), and / or a system comprising multiple processors.

[0153] The internal bus 1206 can be used to establish communication between components of the electronic device 1200.

[0154] Electronic device 1200 is communicatively coupled to the lidar system to be calibrated to control the operation of the lidar system. For example, the calibration method according to this disclosure can be stored in the memory 1204 of electronic device 1200 as computer-readable instructions. Processor 1203 implements the calibration method by reading the stored computer-readable instructions.

[0155] Although specific components are used to describe electronic device 1200, different components may be present in alternative embodiments. For example, electronic device 1200 may include one or more additional processors, memory, network interfaces, and / or I / O interfaces. Additionally, one or more components may not be present in electronic device 1200. Furthermore, although in Figure 12 Individual components are shown, but in some embodiments, some or all of a given component may be integrated into one or more other components in the electronic device 1200.

[0156] This disclosure can be implemented as any combination of apparatus, system, integrated circuit, computer program or program product on a non-transitory computer-readable medium.

[0157] It should be understood that the computer-executable instructions in a computer-readable storage medium or program product according to embodiments of this disclosure can be configured to perform operations corresponding to the above-described device and method embodiments. When referring to the above-described device and method embodiments, embodiments of the computer-readable storage medium or program product will be clear to those skilled in the art, and therefore will not be described again. Computer-readable storage media and program products used to carry or include the above-described computer-executable instructions also fall within the scope of this disclosure. Such storage media may include, but are not limited to, floppy disks, optical disks, magneto-optical disks, memory cards, memory sticks, etc.

[0158] Furthermore, it should be understood that the aforementioned series of processes and devices can also be implemented via software and / or firmware. In the case of implementation via software and / or firmware, the corresponding program constituting the software is stored in the storage medium of the relevant device, and when said program is executed, it is capable of performing various functions.

[0159] For example, the multiple functions included in one unit in the above embodiments can be implemented by separate devices. Alternatively, the multiple functions implemented by multiple units in the above embodiments can be implemented by separate devices respectively. In addition, one of the above functions can be implemented by multiple units. Such configurations are included within the scope of this disclosure.

[0160] In this disclosure, the steps described in the flowcharts include not only processes executed sequentially in the stated order, but also processes executed in parallel or individually, rather than necessarily sequentially. Furthermore, even within steps involving sequential processing, the order can be appropriately altered.

[0161] This disclosure also provides a computer program product, including computer instructions. When executed by a processor, these computer instructions implement the various processes of the above-described lidar delay correction method embodiments and achieve the same technical effects. To avoid repetition, they will not be described again here.

[0162] The terms "comprising," "including," or any other variations thereof used in embodiments of this disclosure are intended to cover a 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.

[0163] The term "or" in this disclosure means inclusive "or," not exclusive "or." A reference to a "first" component does not necessarily require the provision of a "second" component. Furthermore, unless explicitly indicated, "first" or "second" component does not imply a restriction on the order in which the components are mentioned. The term "based on" means "at least partially based on."

[0164] The embodiments of this disclosure have been described above with reference to the accompanying drawings. However, this disclosure is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this disclosure without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this disclosure.

Claims

1. A method for correcting time delay in a lidar system, characterized in that, include: Obtain the first distance between the marker and the lidar, wherein the center of the marker, the centroid of the point cloud of the first module of the lidar, and the optical center of the lidar are on the same straight line, and the point cloud of the first module includes N initial points, where N is an integer greater than 1; Obtain the second distance between the N initial points, where the second distance is the distance between the initial point and the optical center of the lidar; Determine a first target point among the N initial points, wherein the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold; Based on the second distance and the first distance of the first target point, the corrected delay corresponding to the first module is calculated; The delay of the first module is corrected based on the corrected delay corresponding to the first module.

2. The method as described in claim 1, characterized in that, After obtaining the second distance between the N initial points, the method further includes: Obtain the azimuth and / or elevation angles of the N initial points relative to the optical center of the lidar; The absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold, and the azimuth and / or elevation angle of the first target point relative to the optical center of the lidar meets preset conditions. The preset conditions include at least one of the following: The difference between the azimuth angle of the first target point relative to the optical center of the lidar and the azimuth angle of the adjacent initial point is less than a first set angle threshold. The difference between the elevation angle of the first target point relative to the optical center of the lidar and the elevation angle of the adjacent initial point is less than a second set angle threshold.

3. The method as described in claim 1, characterized in that, After calculating the corrected delay corresponding to the first module based on the second distance and the first distance from the first target point, the method further includes: A first point cloud plane formed by the point cloud of the first module and a second point cloud plane formed by the point cloud of the second module of the lidar are obtained. The second module is adjacent to the first module. Both the second module and the first module are transmitting modules or receiving modules of the lidar. The second point cloud plane is less than or equal to the first point cloud plane. Calculate the third distance between the second point cloud plane and the first point cloud plane; Calculate the first relative time delay, which is the quotient of the third distance and twice the speed of light; The sum of the first relative delay and the corrected delay corresponding to the first module is set as the corrected delay of the second module.

4. The method as described in claim 3, characterized in that, The second point cloud plane includes multiple points, and calculating the third distance between the second point cloud plane and the first point cloud plane includes: By performing surface fitting on the multiple points, the surface equation corresponding to the cloud plane of the second point is obtained; Calculate the equation of the straight line corresponding to at least one second target point, wherein the at least one second target point and the optical center of the lidar are located on a straight line, and the at least one second target point is a point in the first point cloud plane; Based on the corresponding straight line equation and the surface equation, the intersection point corresponding to the at least one second target point is calculated, and the intersection point is located in the second point cloud plane; The average distance between the at least one second target point and its corresponding intersection point is set as the third distance.

5. The method as described in claim 3, characterized in that, After setting the sum of the first relative delay and the corrected delay corresponding to the first module as the corrected delay of the second module, the method further includes: A third point cloud plane is obtained from the point cloud of the third module of the lidar. The third module is also adjacent to the second module. Both the third module and the second module are transmitting or receiving modules of the lidar. The third point cloud plane is less than or equal to the second point cloud plane. Calculate the fourth distance between the third point cloud plane and the second point cloud plane; Calculate the second relative time delay, which is the quotient of the fourth distance and twice the speed of light; The quotient of the fourth distance and twice the speed of light is set as the second relative delay, and the sum of the second relative delay and the corrected delay corresponding to the second module is set as the corrected delay of the third module.

6. The method according to any one of claims 1 to 5, characterized in that, The calculation of the corrected time delay corresponding to the first module based on the second distance and the first distance from the first target point includes at least one of the following: When the first target point is one of the N initial points, calculate the second distance of the first target point and the first difference of the first distance, and set the quotient of the first difference and twice the speed of light as the correction delay corresponding to the first module; When the first target point is one of the N initial points, the average value of the second distances of the multiple initial points and the second difference of the first distance are calculated, and the quotient of the second difference and twice the speed of light is set as the correction delay corresponding to the first module.

7. A laser radar delay correction device, characterized in that, include: The first acquisition module is used to acquire the first distance between the marker and the lidar. The center of the marker, the centroid of the point cloud of the first module of the lidar and the optical center of the lidar are on the same straight line. The point cloud of the first module includes N initial points, where N is an integer greater than 1. The second acquisition module is used to acquire the second distance of the N initial points, wherein the second distance is the distance between the initial point and the optical center of the lidar; The determination module is used to determine a first target point among the N initial points, wherein the absolute value of the difference between the second distance and the first distance of the first target point is less than a set distance threshold. The first calculation module is used to calculate the corrected time delay corresponding to the first module based on the second distance and the first distance of the first target point; The correction module is used to correct the delay of the first module based on the correction delay corresponding to the first module.

8. An electronic device, characterized in that, It includes a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps of the lidar delay correction method as described in any one of claims 1 to 6.

9. A readable storage medium for storing a program, characterized in that, When the program is executed by the processor, it implements the steps in the lidar delay correction method as described in any one of claims 1 to 6.

10. A computer program product, characterized in that, It includes computer instructions that, when executed by a processor, implement the steps of the lidar delay correction method as described in any one of claims 1 to 6.

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