Correction method and device of galvanometer, radar and storage medium

Abstract

The invention provides a galvanometer correction method and device, a radar and a storage medium. The method comprises the steps of obtaining point clouds of splicing areas among multiple channels of the radar; according to the point cloud of the splicing area, determining a layering characteristic value of the splicing area; wherein the layering characteristic value is used for representing the layering degree of the point cloud of the splicing area; under the condition that the hierarchical characteristic value is greater than a preset threshold value, determining an adjustment coefficient of a driving signal of a galvanometer in the radar; and adjusting the driving signal according to the adjusting coefficient, so that the layering characteristic value of the splicing area is smaller than the preset threshold value under the condition that the galvanometer is driven by the adjusted driving signal. According to the method, the galvanometer can be corrected in time, and the scanning precision of the galvanometer can be improved.

Description

Technical Field

[0001] The present application relates to the field of radar, and more specifically, to a calibration method and device for a galvanometer in the field of radar, a radar and a storage medium. Background Art

[0002] LiDAR can build a 3D image of the surroundings. LiDAR uses a micro-electro-mechanical system (MEMS) micro-vibration mirror as a beam scanning structure. The scanning accuracy of the visor in the existing MEMS LiDAR is determined by the mapping relationship between the calibration feedback signal and the spatial coordinate position. It relies on a specific mode and a specific site and has no automatic correction function. As the device application ages, the use of the old mapping relationship will make the point cloud position inaccurate, resulting in a decrease in scanning accuracy. Summary of the invention

[0003] The present application provides a galvanometer correction method, device, radar and storage medium. The method can correct the galvanometer in a timely manner, which is beneficial to improving the scanning accuracy of the galvanometer.

[0004] In a first aspect, a galvanometer correction method is provided, the method comprising: obtaining a point cloud of a stitching area between multiple channels of a radar; determining a stratification characteristic value of the stitching area based on the point cloud of the stitching area; wherein the stratification characteristic value is used to characterize the stratification degree of the point cloud of the stitching area; when the stratification characteristic value is greater than a preset threshold, determining an adjustment coefficient of a drive signal for a galvanometer in the radar; and adjusting the drive signal according to the adjustment coefficient so that when the galvanometer is driven by the adjusted drive signal, the stratification characteristic value of the stitching area is less than a preset threshold.

[0005] In the above technical solution, by obtaining the point cloud of the splicing area between multiple channels of the radar, the hierarchical characteristic value of the splicing area is determined according to the point cloud of the splicing area. Since the hierarchical characteristic value is used to characterize the hierarchical degree of the point cloud of the splicing area, if the hierarchical characteristic value is greater than the preset threshold, it means that the hierarchical degree of the point cloud of the splicing area is large, and the galvanometer needs to be corrected in time. During the correction, the adjustment coefficient of the driving signal of the galvanometer is first determined, and then the driving signal is adjusted according to the adjustment coefficient, so that when the galvanometer is driven by the adjusted driving signal, the hierarchical characteristic value of the splicing area is less than the preset threshold, that is, when the galvanometer is driven by the adjusted driving signal, the hierarchical characteristic value of the splicing area is less than the preset threshold, and the hierarchical degree of the splicing area is reduced compared to before the correction, thereby realizing the improvement of the scanning accuracy of the galvanometer by timely correction of the galvanometer. In addition, the correction process does not rely on a specific mode and a specific site, but relies on the point cloud of the splicing area. The number of point clouds in the splicing area is relatively small, so the computing power required to complete the correction is small, which is conducive to improving the efficiency of the correction.

[0006] In combination with the first aspect, in some possible implementations, determining the hierarchical feature value of the stitching area according to the point cloud of the stitching area includes: for each to-be-matched point in the first channel of the stitching area, determining a target point matching the to-be-matched point in the second channel of the stitching area, and obtaining a matching point pair corresponding to each group of adjacent channels in the multiple channels; wherein one matching point pair includes a to-be-matched point located in the first channel and a target point located in the second channel, the target point being a point in the second channel that is closest to the to-be-matched point, and the first channel and the second channel belonging to a group of adjacent channels in the multiple channels; calculating, according to the matching point pairs corresponding to each group of adjacent channels, distance feature values ​​corresponding to adjacent channels that meet preset requirements; wherein the distance feature values ​​are determined based on the distance between two points in the matching point pairs corresponding to each group of adjacent channels; and determining the hierarchical feature value of the stitching area according to the distance feature values ​​corresponding to the adjacent channels that meet the preset requirements.

[0007] In combination with the first aspect and the above implementation manner, in some possible implementation manners, before calculating the distance feature values ​​corresponding to the adjacent channels that meet the preset requirements according to the matching point pairs corresponding to the groups of adjacent channels, the method further includes: determining the number of matching point pairs corresponding to the groups of adjacent channels;

[0008] The adjacent channels whose number of matching point pairs is greater than a preset number threshold are determined as the adjacent channels that meet the preset requirements.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, for each to-be-matched point in the first channel of the stitching area, determining a target point that matches the to-be-matched point in the second channel of the stitching area includes: for each to-be-matched point in the first channel of the stitching area, determining a search range corresponding to the to-be-matched point; and determining a target point that matches the to-be-matched point in the second channel of the stitching area within the search range corresponding to the to-be-matched point.

[0010] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, for each point to be matched in the first channel of the stitching area, determining the search range corresponding to the point to be matched includes: determining the polar coordinates and / or spatial coordinates of the point to be matched; determining the search range corresponding to the point to be matched based on the polar coordinates and / or spatial coordinates; wherein the spatial distance between each point in the search range and the point to be matched is less than a preset distance threshold, and / or the azimuth deviation between each point in the search range and the point to be matched is less than a preset azimuth threshold and the pitch angle deviation is less than a preset pitch angle threshold.

[0011] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the spatial distance between each point in the search range and the point to be matched is less than the preset distance threshold corresponding to each point, and the preset distance threshold corresponding to each point is determined based on the spatial distance and preset angle between each point in the search range and the point to be matched.

[0012] In combination with the first aspect and the above implementation manner, in some possible implementation manners, the hierarchical feature value includes a horizontal hierarchical feature value and a vertical hierarchical feature value; for each to-be-matched point in the first channel of the stitching area, determining a target point matching the to-be-matched point in the second channel of the stitching area, and obtaining a pair of matching points corresponding to each group of adjacent channels in the multiple channels, comprises:

[0013] According to the point cloud in the first channel of the stitching area, a first type of point cloud set and a second type of point cloud set are screened out; wherein, the angle between the line between any two adjacent points in the first type of point cloud set and the Z axis is less than the first preset angle, and the angle between the line between any two adjacent points in the second type of point cloud set and the X axis is less than the second preset angle; for each first type of point to be matched in the first type of point cloud set, a first target point matching the first type of point to be matched is determined in the second channel of the stitching area, and a first type of matching point pair corresponding to each group of adjacent channels in the multiple channels is obtained; wherein, a first type of matching point pair includes a first type of point to be matched located in the first channel and a first target point located in the second channel, and the first target point is the point in the second channel that is closest to the first type of point to be matched; for each second type of point to be matched in the second type of point cloud set, a second target point matching the second type of point to be matched is determined in the second channel of the stitching area, and a first type of matching point pair corresponding to each group of adjacent channels in the multiple channels is obtained. The second type of matching point pairs corresponding to each group of adjacent channels; wherein a second type of matching point pair includes a second type of to-be-matched point located in the first channel and a second target point located in the second channel, and the second target point is a point in the second channel that is closest to the second type of to-be-matched point; the calculating of distance feature values ​​corresponding to adjacent channels that meet preset requirements according to the matching point pairs corresponding to each group of adjacent channels includes: calculating first distance feature values ​​corresponding to adjacent channels that meet preset requirements according to the first type of matching point pairs corresponding to each group of adjacent channels; calculating second distance feature values ​​corresponding to adjacent channels that meet preset requirements according to the second type of matching point pairs corresponding to each group of adjacent channels; the determining of layered feature values ​​of the splicing area according to the distance feature values ​​corresponding to adjacent channels that meet preset requirements includes: determining the horizontal layered feature value according to the first distance feature value corresponding to adjacent channels that meet preset requirements; and determining the vertical layered feature value according to the second distance feature value corresponding to adjacent channels that meet preset requirements.

[0014] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, determining the horizontal stratification characteristic value based on the first distance characteristic value corresponding to the adjacent channels that meet the preset requirements includes: summing the first distance characteristic values ​​corresponding to the adjacent channels that meet the preset requirements to obtain the sum of the first distance characteristic values; determining the horizontal stratification characteristic value based on the sum of the first distance characteristic values ​​and the number of groups of adjacent channels that meet the preset requirements.

[0015] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, when the stitching area of ​​the multiple channels includes: a first stitching area and a second stitching area located at the edge and at least one third stitching area located between the first stitching area and the second stitching area, determining the vertical stratification characteristic value according to the second distance characteristic value corresponding to the adjacent channels that meet the preset requirements includes: determining a first reference vertical stratification characteristic value according to the second distance characteristic value corresponding to the adjacent channels of the first stitching area and the second distance characteristic value corresponding to the adjacent channels of the second stitching area among the adjacent channels that meet the preset requirements; determining a second reference vertical stratification characteristic value according to the second distance characteristic value corresponding to the adjacent channels of the at least one third stitching area among the adjacent channels that meet the preset requirements; and determining a vertical stratification characteristic value according to the first reference vertical stratification characteristic value and the second reference vertical stratification characteristic value.

[0016] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, determining the vertical stratification characteristic value based on the first reference vertical stratification characteristic value and the second reference vertical stratification characteristic value includes: calculating the vertical stratification characteristic value based on the first reference vertical stratification characteristic value, the first weight corresponding to the first reference vertical stratification characteristic value, the second reference vertical stratification characteristic value, the second weight corresponding to the second reference vertical stratification characteristic value, the second distance characteristic value corresponding to the adjacent channels of the first stitching area, the third weight corresponding to the first stitching area, the second distance characteristic value corresponding to the adjacent channels of the second stitching area, and the fourth weight corresponding to the second stitching area; wherein the first weight is greater than the second weight, the second weight is greater than the third weight, and the second weight is greater than the fourth weight.

[0017] In combination with the first aspect and the above-mentioned implementation manner, in some possible implementation manners, the determining of the adjustment coefficient of the driving signal of the galvanometer in the radar includes: calculating the actual normal vector of the galvanometer according to the spatial coordinates of each point in the point cloud of the stitching area and the incident vector corresponding to each point; determining multiple reference coefficients within a preset reference coefficient range with a preset step value; for each of the reference coefficients, determining the hierarchical characteristic value of the stitching area under the action of the reference coefficient; and selecting, from the multiple reference coefficients, the hierarchical characteristic value of the stitching area under the action of each of the reference coefficients. The reference coefficient with the smallest eigenvalue is used as the adjustment coefficient; wherein, the determination of the hierarchical eigenvalue of the stitching area under the action of the reference coefficient includes: taking the product of the reference coefficient and the actual normal vector as the reference normal vector; determining the reference output vector corresponding to each point according to the reference normal vector and the incident vector corresponding to each point; determining the updated point corresponding to each point according to the reference output vector corresponding to each point and the distance between each point and the origin of the galvanometer, and obtaining an updated point cloud; determining the hierarchical eigenvalue of the stitching area under the action of the reference coefficient according to the updated point cloud.

[0018] In combination with the first aspect and the above-mentioned implementation manner, in some possible implementation manners, the adjustment coefficient includes: a first adjustment coefficient for the horizontal field of view and a second adjustment coefficient for the vertical field of view; for each of the reference coefficients, determining the layered characteristic value of the stitching area under the action of the reference coefficient includes: for each of the reference coefficients, determining the horizontal layered characteristic value and the vertical layered characteristic value of the stitching area under the action of the reference coefficient; according to the layered characteristic value of the stitching area under the action of each of the reference coefficients, selecting the reference coefficient that minimizes the layered characteristic value of the stitching area from among the multiple reference coefficients as the adjustment coefficient includes: according to the horizontal layered characteristic value of the stitching area under the action of each of the reference coefficients, selecting the reference coefficient that minimizes the layered characteristic value of the stitching area from among the multiple reference coefficients as the adjustment coefficient. The method comprises: selecting a reference coefficient with the smallest value as the first adjustment coefficient; selecting a reference coefficient that minimizes the vertical layered characteristic value of the stitching area from among the multiple reference coefficients according to the vertical layered characteristic value of the stitching area under the action of each of the reference coefficients as the second adjustment coefficient; determining the horizontal layered characteristic value and the vertical layered characteristic value of the stitching area under the action of the reference coefficients, comprising: determining a first reference normal vector according to the reference coefficients and the actual normal vector; wherein the azimuth component of the first reference normal vector is the product of the reference coefficient and the azimuth component of the actual normal vector, and the pitch component of the first reference normal vector is the same as the pitch component of the actual normal vector; determining a first reference outgoing vector corresponding to each point according to the first reference normal vector and the incident vector corresponding to each point;

[0019] According to the first reference exit vector corresponding to each point and the distance between each point and the origin of the galvanometer, the updated first-class points corresponding to each point are determined to obtain an updated first-class point cloud; according to the updated first-class point cloud, the horizontal layered characteristic value of the stitching area under the action of the reference coefficient is determined; according to the reference coefficient and the actual normal vector, a second reference normal vector is determined; wherein the pitch angle component of the second reference normal vector is the product of the reference coefficient and the pitch angle component of the actual normal vector, and the azimuth angle component of the second reference normal vector is the same as the azimuth angle component of the actual normal vector; according to the second reference normal vector and the incident vector corresponding to each point, the second reference exit vector corresponding to each point is determined; according to the second reference exit vector corresponding to each point and the distance between each point and the origin of the galvanometer, the updated second-class points corresponding to each point are determined to obtain an updated second-class point cloud; according to the updated second-class point cloud, the vertical layered characteristic value of the stitching area under the action of the reference coefficient is determined.

[0020] In a second aspect, a galvanometer correction device is provided, which includes: a point cloud acquisition module for acquiring a point cloud of a stitching area between multiple channels of a radar; a layered characteristic value determination module for determining a layered characteristic value of the stitching area based on the point cloud of the stitching area; wherein the layered characteristic value is used to characterize the degree of stratification of the point cloud of the stitching area; an adjustment coefficient determination module for determining an adjustment coefficient of a drive signal for a galvanometer in the radar when the layered characteristic value is greater than a preset threshold; and an adjustment module for adjusting the drive signal according to the adjustment coefficient so that when the galvanometer is driven by the adjusted drive signal, the layered characteristic value of the stitching area is less than a preset threshold.

[0021] In a third aspect, a radar is provided, comprising a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, so that the radar executes the method in the first aspect or any possible implementation of the first aspect.

[0022] In a fourth aspect, a computer program product is provided, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the method in the first aspect or any possible implementation of the first aspect.

[0023] In a fifth aspect, a computer-readable storage medium is provided, which stores a computer program code. When the computer program code runs on a computer, the computer executes the method in the above-mentioned first aspect or any possible implementation manner of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of an application scenario of a laser radar provided in an embodiment of the present application;

[0025] Figure 2 is a schematic diagram of the structure of a laser radar provided in an embodiment of the present application;

[0026] Figure 3 is a schematic diagram of a scene of field scanning provided in an embodiment of the present application;

[0027] Figure 4 is a schematic flow chart of a galvanometer calibration method provided in an embodiment of the present application;

[0028] Figure 5 is a distribution diagram of a point cloud provided in an embodiment of the present application;

[0029] Figure 6 is a schematic diagram of an optical path in a radar provided in an embodiment of the present application;

[0030] Figure 7 It is a structural schematic diagram of a galvanometer correction device provided in an embodiment of the present application;

[0031] Figure 8 It is a schematic diagram of the structure of a radar provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0033] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0034] In one or more embodiments of this specification, see Figure 1 , Figure 1 FIG. 1 shows a schematic diagram of an application scenario based on laser radar provided in this specification. Figure 1 As shown, the application scenario includes: a laser radar 101 and a vehicle 102. The laser radar 101 is installed on various vehicles 102 that need to detect the surrounding environment. The vehicle 102 can be, for example, a vehicle, a ship, an aircraft, etc. Optionally, when the vehicle 102 is a vehicle, the laser radar can be installed on the front, rear, roof, side of the vehicle or any other body position where the laser radar can be fixed. It should be noted that this embodiment only takes the laser radar 101 installed on the vehicle 102 as an example. In a specific implementation, the laser radar 101 can be installed on any device that needs to detect the surrounding environment.

[0035] In one or more embodiments of this specification, see Figure 2 , Figure 2The schematic diagram of the structure of a laser radar provided in this specification is shown, including a transmitting device 10, a scanning device 20 and a receiving device 30. Among them, the transmitting device 10 is used to transmit a detection laser; the scanning device 20 is used to receive the detection laser and emit the detection laser to the detection field of view; the scanning device 20 is also used to receive the echo laser and deflect the echo laser to the receiving device 30; the receiving device 30 is used to receive the echo laser. The scanning device 20 may include at least a galvanometer. It is understood that this specification does not limit the number and combination of hardware included in the scanning device, and the scanning device shown in this specification may also include other scanning devices besides the galvanometer.

[0036] The transmitting device 10 may include a laser; schematically, when the laser radar performs field scanning, the laser emits a pulsed outgoing detection laser and directs it to the galvanometer in the scanning device 20, and receives the detection laser through the galvanometer in the scanning device, and emits the detection laser to the detection field, and receives the echo laser generated by the echo object after reflection, and deflects the echo laser to the receiving device; and then receives the echo laser through the receiving device. Usually, a scanning point is obtained after solving based on a detection laser and the corresponding echo laser.

[0037] In one or more embodiments of this specification, the laser radar may use a galvanometer to scan the field of view. Figure 3 As shown, Figure 3 1 is a schematic diagram of a field of view scanning scenario provided in this specification, wherein the laser 11 can emit a detection laser projected on the galvanometer 12, which is reflected by the galvanometer 12; and the galvanometer 12 receives the echo laser and deflects the echo laser to the receiving device, and the receiving device ( Figure 3 When the galvanometer 12 is a two-dimensional galvanometer, the galvanometer 12 can swing two-dimensionally around the X-axis and the Y-axis, thereby changing the emission scanning angle of the detection laser in two directions, realizing scanning over a large area, and obtaining a distance image within the scanning range.

[0038] The scanning accuracy of the laser radar is an important parameter of the laser radar, which determines the accuracy of the surrounding environment detected by the laser radar to a certain extent. However, during the use of the laser radar, as the device ages, the problem of reduced scanning accuracy often occurs. The inventors of the present application found that the main reason for the reduced scanning accuracy is that the scanning accuracy of the existing laser radar is determined by the mapping relationship between the calibration feedback signal and the spatial coordinate position, which depends on a specific mode and a specific site, and has no automatic correction function. As the device ages, the old mapping relationship will still be used, which will make the point cloud position inaccurate. The old mapping relationship is inaccurate, which will cause the point clouds of different channels to be layered, and the greater the deviation of the old mapping relationship from the actual mapping relationship that should be adopted, the more obvious the layering, resulting in a decrease in scanning accuracy. Based on this, the embodiment of the present application provides a method for correcting the galvanometer, and timely correcting the galvanometer, which is conducive to improving the scanning accuracy of the galvanometer.

[0039] The execution subject of the galvanometer correction method provided in the embodiment of the present application can be a radar, specifically a control and processing unit inside a laser radar, or a terminal device connected to the laser radar. The terminal device can be a mobile terminal such as a smart phone, tablet computer or wearable device, or a computer, cloud server, radar-assisted computer and other devices in various application scenarios. It should be noted that. The following is an example of the execution subject being a laser radar:

[0040] Figure 4 It is a schematic flow chart of a galvanometer calibration method provided in an embodiment of the present application.

[0041] For example, Figure 4 As shown, the method includes:

[0042] Step 401: Obtain a point cloud of a stitching area between multiple channels of a radar.

[0043] Step 402: Determine a hierarchical feature value of the stitching area according to the point cloud of the stitching area; wherein the hierarchical feature value is used to characterize the hierarchical degree of the point cloud of the stitching area.

[0044] Step 403: when the hierarchical characteristic value is greater than a preset threshold, determining an adjustment coefficient of a driving signal for a galvanometer in the radar.

[0045] Step 404: The driving signal is adjusted according to the adjustment coefficient, so that when the galvanometer is driven by the adjusted driving signal, the layered characteristic value of the splicing area is less than a preset threshold.

[0046] exist Figure 4In the embodiment shown, by obtaining the point cloud of the splicing area between multiple channels of the radar, the layered characteristic value of the splicing area is determined according to the point cloud of the splicing area. Since the layered characteristic value is used to characterize the layered degree of the point cloud of the splicing area, if the layered characteristic value is greater than the preset threshold, it means that the layered degree of the point cloud of the splicing area is large, and the galvanometer needs to be corrected in time. During the correction, the adjustment coefficient of the drive signal of the galvanometer is first determined, and then the drive signal is adjusted according to the adjustment coefficient, so that when the galvanometer is driven by the adjusted drive signal, the layered characteristic value of the splicing area is less than the preset threshold, that is, when the galvanometer is driven by the adjusted drive signal, the layered characteristic value of the splicing area is less than the preset threshold, and the layered degree of the splicing area is reduced compared to before the correction, thereby realizing the improvement of the scanning accuracy of the galvanometer by timely correction of the galvanometer. In addition, the correction process does not rely on a specific mode and a specific site, but relies on the point cloud of the splicing area. The number of point clouds in the splicing area is relatively small, so the computing power required to complete the correction is small, which is conducive to improving the efficiency of the correction.

[0047] It is understandable that in order to achieve a larger detection area, the method of stitching multiple fields of view is generally used to expand the area. Multiple fields of view correspond to multiple channels, each field of view corresponds to a channel, and each channel consists of a group of laser transmitters, laser receivers, hardware circuits and optical elements.

[0048] For example, it is assumed that the multiple channels of the radar are Figure 5 The five channels shown correspond to five fields of view, and the five fields of view are spliced ​​to form four splicing areas, which are: splicing area 1 between channel 1 and channel 2, splicing area 2 between channel 2 and channel 3, splicing area 3 between channel 3 and channel 4, and splicing area 4 between channel 4 and channel 5. Figure 5 The four white arrows in the figure actually point to the four splicing areas respectively.

[0049] Below Figure 4 The specific implementation of each step in the embodiment shown is described as follows:

[0050] In step 401, a stitching area is formed between any two adjacent channels of the radar, so that point clouds of all stitching areas between the multiple channels can be obtained. Assume that the multiple channels of the radar are Figure 5 The five channels shown in the figure can obtain the point cloud of the four stitching areas formed by the five channels of the radar, that is, obtain Figure 5 The point cloud of stitching area 1, the point cloud of stitching area 2, the point cloud of stitching area 3, and the point cloud of stitching area 4.

[0051] Optionally, the point cloud of the splicing area between multiple channels of the radar can be obtained at every preset time period for subsequent correction process. That is to say, the above steps 401 to 404 can be performed once every preset time period, without the need to obtain point cloud computing in real time. Among them, the preset time period can be set according to actual needs, such as one day, one week, half a month, etc. Optionally, the point cloud of the splicing area between the multiple channels of the radar can be obtained during the initialization process after each power-on of the radar for subsequent correction process.

[0052] In step 402, a hierarchical characteristic value of the stitching area is determined based on the point cloud of the stitching area; wherein the hierarchical characteristic value is used to characterize the degree of stratification of the point cloud of the stitching area, and a larger hierarchical characteristic value indicates a greater degree of stratification, and a smaller hierarchical characteristic value indicates a smaller degree of stratification.

[0053] It is understandable that a splicing area includes 2 adjacent channels. Based on each point in one channel of the splicing area, points matching the above points can be found in another channel of the splicing area to obtain several matching point pairs corresponding to the splicing area. Then, according to the distance between the two points in each matching point pair, the reflectivity difference and other features, the hierarchical feature value of the splicing area is obtained. For example, the distance and reflectivity difference between the two points in each matching point pair are used as the distance and reflectivity difference corresponding to each matching point pair. According to the distance and / or reflectivity difference corresponding to the several matching point pairs corresponding to the splicing area, the corresponding distance average value and / or the average value of the reflectivity difference of the splicing area are calculated, and the hierarchical feature value of the splicing area is calculated according to the average value of the distance average value and / or the average value of the reflectivity difference. For example, the distance average value or the average value of the reflectivity difference can be used as the hierarchical feature value of the splicing area. Alternatively, the distance average value and the reflectivity difference are further weighted to obtain the hierarchical feature value of the splicing area.

[0054] Exemplarily, the method for determining the plurality of matching point pairs corresponding to the above-mentioned stitching area may be: based on each point in a channel in the stitching area, according to a preset corresponding relationship, searching for points matching each point in another channel of the stitching area. The corresponding relationship includes the corresponding relationship between each point in one channel of the stitching area and each point in another channel, i.e., the matching relationship, so that according to the corresponding relationship, mutually matching or mutually corresponding matching point pairs can be determined in two adjacent channels of the stitching area.

[0055] It can be understood that, in theory, the fields of view corresponding to multiple channels of the radar are all obtained by scanning with the same galvanometer, the number of rows and points in the field of view are the same, and the relative position of each point in the field of view is known. Therefore, the above correspondence can be obtained based on the relative position of each point in the field of view. Figure 5As shown, the corresponding relationship may include: the 10th point in the 1st row in the splicing area of ​​channel 1 corresponds to the 1st point in the 1st row in the splicing area of ​​channel 2, and the 10th point in the 2nd row in the splicing area of ​​channel 1 corresponds to the 1st point in the 2nd row in the splicing area of ​​channel 2, so that the matching point pairs corresponding to the splicing area 1 determined may include: matching point pair 1 (including the 10th point in the 1st row in channel 1 and the 1st point in the 1st row in channel 2), matching point pair 2 (including the 10th point in the 2nd row in channel 1 and the 1st point in the 2nd row in channel 2). In this embodiment, only the determination method of the above two matching point pairs is used as an example for explanation, and the determination method of the remaining matching point pairs can also refer to the above method, and will not be repeated here to avoid repetition.

[0056] Exemplarily, when there are multiple stitching areas, the hierarchical characteristic value of each stitching area can be calculated respectively to obtain the hierarchical characteristic values ​​of all stitching areas. Then, according to the hierarchical characteristic values ​​of all stitching areas, the final hierarchical characteristic value is calculated and used as the result of step 402. For example, the hierarchical characteristic values ​​of all stitching areas can be averaged or weighted averaged to obtain the final hierarchical characteristic value, or the hierarchical characteristic values ​​of all stitching areas can be averaged after removing a maximum value and a minimum value, or a hierarchical characteristic value can be selected from the hierarchical characteristic values ​​of all stitching areas as the final hierarchical characteristic value, such as selecting the hierarchical characteristic value of the stitching area at the edge which is usually distorted and has a large distortion as the final hierarchical characteristic value. However, this embodiment does not specifically limit this.

[0057] In an exemplary embodiment, the implementation of step 402 may include the following steps 4021 to 4023:

[0058] Step 4021: for each to-be-matched point in the first channel of the stitched area, determine a target point that matches the to-be-matched point in the second channel of the stitched area, and obtain matching point pairs corresponding to each group of adjacent channels in the multiple channels.

[0059] A matching point pair includes a matching point located in the first channel and a target point located in the second channel. The target point is the point in the second channel that is closest to the matching point. The first channel and the second channel belong to a group of adjacent channels among multiple channels. For example, the stitching area includes Figure 5 In the stitching area 1 to 4, for the stitching area 1, the first channel and the second channel can be respectively Figure 5 Channels 1 and 2 in the figure can be understood as a group of adjacent channels in the five channels. For the splicing area 2, the first channel and the second channel can be respectively Figure 5Channels 2 and 3 in the figure can be understood as a group of adjacent channels in the five channels. For the splicing area 3, the first channel and the second channel can be respectively Figure 5 Channels 3 and 4 in the figure can be understood as a group of adjacent channels in the five channels. For the splicing area 4, the first channel and the second channel can be respectively Figure 5 Channels 4 and 5 in the diagram can be understood as a group of adjacent channels among the five channels.

[0060] In this embodiment, for each splicing area, the hierarchical characteristic value of the splicing area can be obtained by adopting the method of step 4021 to step 4023. Figure 5 Take the hierarchical feature value of the splicing area 1 in as an example to illustrate:

[0061] Specifically, each point in channel 1 in stitching area 1 can be used as a point to be matched, and a target point matching the point to be matched can be determined in channel 2 to obtain a pair of matching points corresponding to a group of adjacent channels, channels 1 and 2. A pair of matching points includes a point to be matched in channel 1 and a point in channel 2 that is closest to the point to be matched.

[0062] For example, each to-be-matched point in channel 1 in the stitching area 1 can be traversed, and the distance between the to-be-matched point and each point in channel 2 in the stitching area 1 can be calculated, and then the point with the smallest distance from the to-be-matched point in the calculated distance can be selected as the target point that matches the to-be-matched point. The currently traversed to-be-matched point and the target point that matches the to-be-matched point are taken as a matching point pair, and after traversing each to-be-matched point in channel 1 in the stitching area 1, all matching point pairs corresponding to the set of adjacent channels of channels 1 and 2 are obtained.

[0063] For the group of adjacent channels, channels 2 and 3, each to-be-matched point in channel 2 in the stitching area 2 can be traversed, the distance between the to-be-matched point and each point in channel 3 in the stitching area 2 can be calculated, and then the point with the smallest distance to the to-be-matched point in channel 2 is selected in channel 3 as the target point to be matched with the to-be-matched point. After traversing each to-be-matched point in channel 2 in the stitching area 2, all the matching point pairs corresponding to the group of adjacent channels, channels 2 and 3, are obtained. The method for determining the matching point pairs corresponding to other adjacent channels is similar to the method for determining all the matching point pairs corresponding to the group of adjacent channels, channels 1 and 2, and all the matching point pairs corresponding to the group of adjacent channels, channels 2 and 3, and will not be described here to avoid repetition.

[0064] In an exemplary embodiment, the implementation method of the above-mentioned step 4021 may include: for each point to be matched in the first channel of the stitching area, determining the search range corresponding to the point to be matched; within the search range corresponding to the point to be matched, determining the target point in the second channel of the stitching area that matches the point to be matched.

[0065] In this embodiment, a search range is determined for each point to be matched, and the search range of the target point is limited to the search range. Figure 5 , when traversing the to-be-matched points in the splicing area 1 in channel 1, according to the search range corresponding to the to-be-matched point, each candidate point in the search range is screened out, the distance between the to-be-matched point and each candidate point in the splicing area 1 in channel 2 is calculated, and then the candidate point with the smallest distance to the to-be-matched point is selected as the target point matching the to-be-matched point. By determining the search range corresponding to each to-be-matched point, it is helpful to quickly search for the target point matching the to-be-matched point within the search range.

[0066] In an exemplary embodiment, for each to-be-matched point in the first channel of the stitching area, determining the search range corresponding to the to-be-matched point includes: determining the polar coordinates and / or spatial coordinates of the to-be-matched point;

[0067] According to the polar coordinates and / or spatial coordinates, the search range corresponding to the point to be matched is determined. The polar coordinates of the point to be matched can be expressed as (ρ, yaw, pitch), and the spatial coordinates of the point to be matched can be expressed as (x, y, z). The preset distance threshold, the preset azimuth threshold, and the preset pitch angle threshold can all be set according to actual needs.

[0068] Exemplarily, the search range corresponding to the point to be matched can be determined based on the spatial coordinates of the point to be matched. The spatial distance between each point in the search range and the point to be matched is less than a preset distance threshold. For example, a circular area with the point to be matched as the center and the preset distance threshold as the radius can be used as the search range corresponding to the point to be matched, so that the spatial distance between each point in the circular area and the point to be matched is less than the preset distance threshold. However, this embodiment does not specifically limit the shape of the search range. The spatial distance can be determined based on the spatial coordinates of the point to be matched and the spatial coordinates of the points in the search range.

[0069] Exemplarily, the search range corresponding to the point to be matched can be determined based on the polar coordinates of the point to be matched. The azimuth deviation between each point in the search range and the point to be matched is less than a preset azimuth threshold and the elevation deviation is less than a preset elevation threshold. For example, a region centered on the polar coordinates of the point to be matched can be determined based on a preset azimuth threshold and a preset elevation threshold, and the region is used as the above-mentioned search range. Optionally, the preset azimuth threshold can be 0.2, and the preset elevation threshold can be 0.3. However, this embodiment does not specifically limit the specific sizes of the preset azimuth threshold and the preset elevation threshold.

[0070] Exemplarily, the search range corresponding to the point to be matched can be determined based on the polar coordinates and spatial coordinates of the point to be matched. Among them, the azimuth deviation between each point in the search range and the point to be matched is less than a preset azimuth threshold and the pitch deviation is less than a preset pitch threshold, and the spatial distance between each point in the search range and the point to be matched is less than a preset distance threshold. In other words, the search range determined in this example is the intersection range of the search range determined based on the polar coordinates and the search range determined based on the spatial coordinates.

[0071] In an exemplary embodiment, the spatial distance between each point in the search range and the point to be matched is less than a preset distance threshold corresponding to each point, and the preset distance threshold corresponding to each point is determined based on the spatial distance between each point in the search range and the point to be matched and a preset angle. That is, in this embodiment, the preset distance threshold may not be fixed, but a preset distance threshold may be corresponding to each point in the search range, so that the determined search range is more accurate.

[0072] For example, assuming that the spatial distance between point A in the search range and point B to be matched is recorded as p1_XY, and the preset angle is recorded as α, the preset distance threshold corresponding to point A can be calculated by the following formula: p1_XY*sinα. The preset angle can be less than or equal to the angle corresponding to the splicing area, for example, the preset angle can be less than or equal to 2°.

[0073] Step 4022: Calculate the distance feature values ​​corresponding to the adjacent channels that meet the preset requirements according to the matching point pairs corresponding to each group of adjacent channels.

[0074] The preset requirements may be set according to actual needs. For example, each group of adjacent channels may be considered to be adjacent channels that meet the preset requirements.

[0075] For example, considering that the layered characteristic value of the stitching area located at the edge may be larger, and the layered characteristic value of the stitching area located in the middle may be smaller, if the layered characteristic value of the stitching area located at the edge can be smaller than the preset threshold through correction, then theoretically the layered characteristic value of the stitching area located in the middle can also be smaller than the preset threshold. Therefore, the adjacent channels in the stitching area located at the edge can be determined as adjacent channels that meet the preset requirements, and the subsequent correction process is performed based on the adjacent channels that meet the preset requirements, which is conducive to improving the correction efficiency to a certain extent while ensuring the correction effect. For example, refer to Figure 5 The stitching areas at the edges include stitching area 1 at the left edge and stitching area 4 at the right edge, and the stitching areas in the middle may include stitching areas 2 and 3, so that the adjacent channels that meet the preset requirements may be a group of adjacent channels of channels 1 and 2 and a group of adjacent channels of channels 4 and 5.

[0076] In an exemplary embodiment, before step 4022, the method further includes: determining the number of matching point pairs corresponding to each group of adjacent channels; and determining adjacent channels with a number of matching point pairs greater than a preset number threshold as adjacent channels that meet preset requirements.

[0077] That is to say, in this embodiment, the adjacent channels that meet the preset requirements are the adjacent channels in which the number of matching point pairs is greater than the preset number threshold. The preset number threshold can be set according to actual needs, and is intended to indicate whether there are a certain number of matching point pairs in a group of adjacent channels to participate in the subsequent distance feature value calculation process.

[0078] For example, see Figure 5 , if the number of matching point pairs corresponding to the set of adjacent channels of channels 1 and 2 is 20, and the number of matching point pairs corresponding to the set of adjacent channels of channels 2 and 3 is 2, assuming that the preset number threshold is 10, then the set of adjacent channels of channels 1 and 2 are adjacent channels that meet the preset requirements, and the set of adjacent channels of channels 2 and 3 are adjacent channels that do not meet the preset requirements.

[0079] It is understandable that there may be interference during the galvanometer scanning process, resulting in a small number of matching point pairs in some adjacent channels. In this case, it will be difficult for these small number of matching point pairs to accurately measure the degree of stratification of the splicing area where the adjacent channels are located. Therefore, in this embodiment, adjacent channels with a number of matching point pairs greater than a preset number threshold are determined as adjacent channels that meet the preset requirements, and adjacent channels with a number of matching point pairs less than or equal to the preset number threshold are filtered out, so as to calculate the distance feature value based on the adjacent channels that meet the preset requirements, and then determine the stratification feature value of the splicing area, which is conducive to improving the accuracy of the determined stratification feature value, and timely correcting the galvanometer when the stratification feature value is greater than the preset threshold, which is conducive to improving the accuracy of the correction.

[0080] In this embodiment, the above distance feature value is determined based on the distance between two points in the matching point pair corresponding to each group of adjacent channels. Since each matching point pair includes two points, the distance between the two points can be calculated according to the spatial coordinates of the two points in each matching point pair, and the distance between the two points can be used as the distance corresponding to the matching point pair. Therefore, the distance feature value corresponding to the group of adjacent channels can be calculated according to the distances corresponding to all matching point pairs in each group of adjacent channels.

[0081] In a possible implementation, an average value of the distances corresponding to all the matching point pairs in the group of adjacent channels may be calculated, and the average value may be used as the distance feature value corresponding to the group of adjacent channels.

[0082] In a possible implementation, the maximum distance and the minimum distance may be removed from the distances corresponding to all matching point pairs in the group of adjacent channels, and then the average value of the distances may be calculated, and the calculated average value of the distances may be used as the distance feature value corresponding to the group of adjacent channels.

[0083] In a possible implementation, the distance with the largest number of occurrences may be selected from the distances corresponding to all the matching point pairs in the group of adjacent channels as the distance feature value corresponding to the group of adjacent channels.

[0084] Step 4023: Determine the hierarchical characteristic value of the splicing area according to the distance characteristic values ​​corresponding to the adjacent channels that meet the preset requirements.

[0085] Optionally, an average value or a weighted average value may be calculated for the distance feature values ​​corresponding to adjacent channels that meet preset requirements, so as to determine the average value or the weighted average value of the distance feature values ​​as the hierarchical feature value of the splicing area.

[0086] In step 403, the preset threshold can be set according to actual needs to measure the degree of stratification of the point cloud in the splicing area. In this embodiment, it can be determined whether the stratification feature value is greater than the preset threshold. If the stratification feature value is less than or equal to the preset threshold, it means that the degree of the point cloud in the splicing area is small, and it can be determined that the galvanometer does not need to be calibrated.

[0087] If the stratification characteristic value is greater than the preset threshold, it means that the degree of stratification of the point cloud in the splicing area is large, and it can be determined that the galvanometer needs to be corrected, and then the adjustment coefficient of the drive signal used to correct the galvanometer can be determined. Then in step 404, the drive signal is adjusted according to the adjustment coefficient, so that when the galvanometer is driven by the adjusted drive signal, the stratification characteristic value of the splicing area is less than the preset threshold, that is, the stratification characteristic value of the splicing area is reduced. The amplitude of the adjusted drive signal can be the product of the adjustment coefficient and the amplitude of the drive signal before adjustment.

[0088] Optionally, the adjustment coefficient can be selected from a plurality of preset reference coefficients, and the plurality of preset reference coefficients can be distributed, for example, between 0.8 and 1.2. In this embodiment, the hierarchical characteristic value of the splicing area after adjusting the driving signal based on different reference coefficients can be calculated, that is, the hierarchical characteristic value of the splicing area under the action of different reference coefficients is determined, and the reference coefficient based on which the hierarchical characteristic value is the smallest is selected as the adjustment coefficient.

[0089] In an exemplary embodiment, the implementation of step 403 may include the following steps 4031 to 4034:

[0090] Step 4031: Calculate the actual normal vector of the galvanometer according to the spatial coordinates of each point in the point cloud of the stitching area and the incident vector corresponding to each point.

[0091] To understand how this step is implemented, we first briefly introduce the optical path in the radar. Figure 6 . Figure 6 The laser emitted by the laser will first irradiate the return mirror, then be reflected by the return mirror and irradiate the galvanometer, and then be emitted after being reflected by the galvanometer to irradiate the target object. Point O3 in the figure is a point on the target object. It can be understood that since the position of the return mirror is fixed, the angle when the return mirror receives the laser and reflects it to the galvanometer is known, that is, Figure 6 The angle θ in is known, and the angle to which the galvanometer rotates at a certain moment is also known. Based on this, the incident angle of O1O2 can be determined in the polar coordinate system established with the center of the galvanometer as the origin. Since the polar coordinates of point O3 in the above polar coordinate system are known, the exit angle of O2O3 can be determined in the above polar coordinate system based on the polar coordinates of point O3. Therefore, according to the incident angle of O1O2 and the exit angle of O2O3, the size of ∠O1O2O3 can be obtained, and the pitch and yaw coordinates of the galvanometer normal vector can be determined based on half of ∠O1O2O3. Since the polar coordinates of each point in the field of view are established with the center of the galvanometer as the origin and the pitch angle and azimuth angle, the galvanometer normal vector can be expressed by pitch and yaw in polar coordinates.

[0092] In this embodiment, for each point in the point cloud of the stitching area, the galvanometer normal vector corresponding to each point in the point cloud of the stitching area can be calculated according to the calculation method of the galvanometer normal vector corresponding to the point O3, and then the actual normal vector of the galvanometer is calculated based on the galvanometer normal vector corresponding to each point obtained. For example, the galvanometer normal vectors corresponding to all points in the point cloud of the stitching area are averaged to obtain the average value of the galvanometer normal vectors, and the average value of the galvanometer normal vectors is used as the actual normal vector of the galvanometer. Alternatively, other calculation methods are used for the galvanometer normal vectors corresponding to all points in the point cloud of the stitching area to obtain the actual normal vector of the galvanometer, and this embodiment does not specifically limit this.

[0093] Step 4032: Determine a plurality of reference coefficients within a preset reference coefficient range with a preset step value.

[0094] Among them, the preset reference coefficient range can be set according to actual needs. In the specific implementation, it can be set based on the adjustable range of the galvanometer drive signal, for example, it can be set to 0.8-1.2. The preset step value reflects the number of determined reference coefficients and the density between multiple reference coefficients, for example, it can be set to 0.01, 0.02, 0.05, etc. Assuming that the preset reference coefficient range is 0.8-1.2 and the preset step value is 0.02, the multiple reference coefficients determined may include: 0.8, 0.82, 0.84, 0.86, 0.88, 0.9, 0.92, 0.94, 0.96, 0.98, 1.02, 1.04, 1.06, 1.08, 1.1, 1.12, 1.14, 1.16, 1.18, 1.2.

[0095] Step 4033: For each reference coefficient, determine the hierarchical characteristic value of the splicing area under the effect of the reference coefficient.

[0096] Wherein, determining the hierarchical characteristic value of the splicing area under the effect of the reference coefficient includes the following S10 to S13:

[0097] S10: The product of the reference coefficient and the actual normal vector is used as the reference normal vector.

[0098] For example, the reference coefficient is recorded as a1, the actual normal vector is recorded as (pitch1, yaw1), and the reference normal vector can be (a1*pitch1, a1*yaw1).

[0099] S11: Determine a reference outgoing vector corresponding to each point according to a reference normal vector and an incident vector corresponding to each point.

[0100] From the above description, we can see that the incident vector corresponding to each point is known, for example, see Figure 6, the incident vector corresponding to point O3 is O1O2. Based on the principle of light reflection, the reference outgoing vector after reflection from the galvanometer can be obtained when the reference normal vector and the incident vector of the galvanometer are known. Therefore, when the reference normal vector and the incident vector corresponding to each point are known, the reference outgoing vector corresponding to each point can be determined.

[0101] S12: Determine the updated point corresponding to each point according to the reference emission vector corresponding to each point and the distance between each point and the origin of the galvanometer to obtain an updated point cloud.

[0102] It can be understood that the reference outgoing vector is actually a ray. If a distance is determined on the ray, a point on the ray can be obtained. The point on the ray is the updated point. Figure 6 , assuming that the reference output vector corresponding to point O3 is a vector starting from point O2 and pointing to the direction of O3', and the distance between point O3 and the origin of the galvanometer is d, then the distance d is taken on the reference output vector to obtain point O3', so that the distance between point O3' and the origin of the galvanometer is d, thereby obtaining the updated point O3' corresponding to point O3. By adopting the above method of determining the updated point O3' corresponding to point O3, the updated points corresponding to each point in the point cloud of the splicing area can be determined, so that each updated point forms an updated point cloud.

[0103] S13: Determine, according to the updated point cloud, the hierarchical characteristic value of the splicing area under the action of the reference coefficient.

[0104] Specifically, the hierarchical feature value of the spliced ​​area under the reference coefficient may be determined by adopting the method in step 402. For example, the point cloud of the spliced ​​area in step 402 is replaced with the updated point cloud to determine the hierarchical feature value of the spliced ​​area.

[0105] It can be understood that since multiple reference coefficients are determined in step 4032, for each reference coefficient, a hierarchical characteristic value of the splicing area can be calculated by the above-mentioned methods S10 to S13, so that multiple hierarchical characteristic values ​​corresponding to multiple reference coefficients can be obtained, and one reference coefficient corresponds to one hierarchical characteristic value.

[0106] Step 4034: According to the hierarchical characteristic value of the splicing area under the effect of each reference coefficient, a reference coefficient that minimizes the hierarchical characteristic value of the splicing area is selected from multiple reference coefficients as an adjustment coefficient.

[0107] It can be seen from the above description that the corresponding hierarchical characteristic values ​​are determined for multiple reference coefficients, so that the minimum hierarchical characteristic value can be selected from the multiple hierarchical characteristic values ​​corresponding to the determined multiple reference coefficients, and the reference coefficient corresponding to the minimum hierarchical characteristic value is used as the adjustment coefficient. For example, this embodiment can determine the hierarchical characteristic values ​​of the splicing area under the action of different reference coefficients within the reference coefficient range of 0.8-1.2. Assuming that the hierarchical characteristic value of the splicing area is the smallest under the action of the reference coefficient of 1.05, 1.05 can be used as the adjustment coefficient.

[0108] In this embodiment, by determining the stratified characteristic value of the stitching area under the action of different reference coefficients, it is equivalent to simulating the correction effect of using different reference coefficients to calibrate the galvanometer. By selecting the reference coefficient that minimizes the stratified characteristic value of the stitching area as the adjustment coefficient, after the galvanometer is corrected by using the adjustment coefficient, the stratified characteristic value of the stitching area can reach the minimum value within the adjustable range of the galvanometer, which greatly reduces the degree of stratification of the stitching area and improves the accuracy of the galvanometer correction.

[0109] In an exemplary embodiment, the implementation of step 4021 may include the following steps S20 to S22:

[0110] S20: Filter out a first type of point cloud set and a second type of point cloud set according to the point cloud in the first channel of the stitching area; wherein the angle between the line between any two adjacent points in the first type of point cloud set and the Z axis is less than a first preset angle, and the angle between the line between any two adjacent points in the second type of point cloud set and the X axis is less than a second preset angle.

[0111] Among them, the first preset angle and the second preset angle can be set according to actual needs, and are usually small, and their specific values ​​are not specifically limited in this embodiment. For the convenience of explanation, the point cloud in the first channel of the splicing area is referred to as point set A. In this embodiment, each point in point set A can be classified to obtain a first type of point cloud set recorded as point set A1 and a second type of point cloud set recorded as point set A2. The points in point set A1 are points in the vertical wall direction, and the points in point set A2 are points in the horizontal ground direction. If the angle between the line connecting at least two adjacent points in point set A and the Z axis is less than the first preset angle, it can be determined that the above-mentioned at least two adjacent points in point set A belong to the points in point set A1. If the angle between the line connecting at least two adjacent points in point set A and the X axis is less than the second preset angle, it can be determined that the above-mentioned at least two adjacent points in point set A belong to the points in point set A2.

[0112] For example, 5 consecutive points can be selected from point set A, and a straight line can be fitted based on the 5 consecutive points. If the angle between the straight line and the X-axis is less than the second preset angle, it can be determined that the 5 consecutive points belong to the points in point set A2. If the angle between the straight line and the Z-axis is less than the first preset angle, it can be determined that the 5 consecutive points belong to the points in point set A1. The straight line obtained by fitting the 5 consecutive points has a more obvious directionality, which facilitates more accurate determination of the angle between the straight line and the X-axis or the Z-axis, so that the point set A can be screened more accurately, thereby improving the accuracy of subsequent calculations based on the screened point sets A1 and A2.

[0113] S21: For each first-class point to be matched in the first-class point cloud set, determine a first target point that matches the first-class point to be matched in the second channel of the stitching area, and obtain first-class matching point pairs corresponding to each group of adjacent channels in the multiple channels; wherein a first-class matching point pair includes a first-class point to be matched located in the first channel and a first target point located in the second channel, and the first target point is the point in the second channel that is closest to the first-class point to be matched.

[0114] In combination with the above example, each point in the point set A1 may be used as a first type of point to be matched, so as to determine a first target point that matches the first type of point to be matched in the second channel of the stitching area.

[0115] For example, suppose point set A1 is located at Figure 5 For channel 1 in point set A1, each first-class matching point in point set A1 can be traversed, and the distance between the first-class matching point and each point in channel 2 of stitching area 1 can be calculated. Then, in the calculated distance, the point with the smallest distance to the first-class matching point is selected as the first target point that matches the first-class matching point. The currently traversed first-class matching point and the first target point that matches the first-class matching point are taken as a first-class matching point pair. After traversing each first-class matching point in point set A1, all first-class matching point pairs corresponding to a group of adjacent channels, channels 1 and 2, are obtained. In a similar way, it can be obtained Figure 5 All first-class matching point pairs corresponding to other groups of adjacent channels in .

[0116] S22: For each second-class point to be matched in the second-class point cloud set, determine a second target point that matches the second-class point to be matched in the second channel of the stitching area, and obtain second-class matching point pairs corresponding to each group of adjacent channels in the multiple channels; wherein a second-class matching point pair includes a second-class point to be matched located in the first channel and a second target point located in the second channel, and the second target point is the point in the second channel that is closest to the second-class point to be matched.

[0117] In combination with the above example, each point in the point set A2 may be used as a second type of point to be matched, so as to determine a second target point that matches the second type of point to be matched in the second channel of the stitching area.

[0118] For example, suppose point set A2 is located at Figure 5 For channel 1 in point set A2, each second-class matching point in point set A2 can be traversed, and the distance between the second-class matching point and each point in channel 2 of stitching area 1 can be calculated. Then, in the calculated distance, the point with the smallest distance to the second-class matching point is selected as the second target point that matches the second-class matching point. The currently traversed second-class matching point and the second target point that matches the second-class matching point are taken as a second-class matching point pair. After traversing each second-class matching point in point set A2, all second-class matching point pairs corresponding to the set of adjacent channels of channels 1 and 2 are obtained. In a similar way, it can be obtained Figure 5 All the second-class matching point pairs corresponding to other groups of adjacent channels in .

[0119] In the case where the above step 4021 is implemented based on the above S20 to S22, the implementation of the above step 4022 may include: calculating the first distance feature value corresponding to the adjacent channels that meet the preset requirements according to the first type of matching point pairs corresponding to each group of adjacent channels; calculating the second distance feature value corresponding to the adjacent channels that meet the preset requirements according to the second type of matching point pairs corresponding to each group of adjacent channels. The corresponding implementation of step 4023 may be: determining the horizontal layer feature value according to the first distance feature value corresponding to the adjacent channels that meet the preset requirements; determining the vertical layer feature value according to the second distance feature value corresponding to the adjacent channels that meet the preset requirements.

[0120] It can be understood that each first-class matching point pair includes two points, and the distance between the two points can be calculated based on the spatial coordinates of the two points in each first-class matching point pair, and the distance between the two points can be used as the distance corresponding to the first-class matching point pair. Therefore, the first distance feature value corresponding to the group of adjacent channels can be calculated based on the distances corresponding to all first-class matching point pairs in each group of adjacent channels. For example, the average value of the distances corresponding to all first-class matching point pairs in the group of adjacent channels can be calculated, and the average value can be used as the first distance feature value corresponding to the group of adjacent channels. Alternatively, after removing the maximum distance and the minimum distance from the distances corresponding to all first-class matching point pairs in the group of adjacent channels, the average value of the distance is calculated, and the calculated average value of the distance is used as the first distance feature value corresponding to the group of adjacent channels.

[0121] The method for determining the second distance feature value is similar to the method for determining the first distance feature value, except that the types of matching point pairs used in the calculation are different. That is, the second distance feature value corresponding to each group of adjacent channels can be calculated based on the distances corresponding to all second-class matching point pairs in the group of adjacent channels. For example, the average value of the distances corresponding to all second-class matching point pairs in the group of adjacent channels can be calculated, and the average value can be used as the second distance feature value corresponding to the group of adjacent channels.

[0122] In an exemplary embodiment, the above-mentioned determining the horizontal stratification characteristic value according to the first distance characteristic value corresponding to the adjacent channels that meet the preset requirements includes: summing the first distance characteristic values ​​corresponding to the adjacent channels that meet the preset requirements to obtain the sum of the first distance characteristic values; determining the horizontal stratification characteristic value according to the sum of the first distance characteristic values ​​and the number of groups of adjacent channels that meet the preset requirements.

[0123] For ease of understanding, the following Figure 5 Take this as an example to illustrate:

[0124] Assume that Figure 5 The four groups of adjacent channels in are all adjacent channels that meet the preset requirements, that is, the number of groups of adjacent channels that meet the preset requirements is 4. The first distance eigenvalue corresponding to the group of adjacent channels of channel 1 and channel 2 is recorded as Wall12, the first distance eigenvalue corresponding to the group of adjacent channels of channel 2 and channel 3 is recorded as Wall23, the first distance eigenvalue corresponding to the group of adjacent channels of channel 3 and channel 4 is recorded as Wall34, and the first distance eigenvalue corresponding to the group of adjacent channels of channel 4 and channel 5 is recorded as Wall45. The horizontal layered eigenvalue WallScore can be calculated by the following formula:

[0125] WallScore=(Wall12+Wall23+Wall34+Wall45) / effect_ch, where effect_ch is the number of adjacent channel groups that meet preset requirements, for example, 4.

[0126] Assume that Figure 5 Among the four groups of adjacent channels, only three groups of adjacent channels meet the preset requirements, namely, the group of adjacent channels between channel 1 and channel 2, the group of adjacent channels between channel 2 and channel 3, and the group of adjacent channels between channel 3 and channel 4. Then the horizontal stratified eigenvalue WallScore can be calculated by the following formula: WallScore = (Wall12+Wall23+Wall34) / 3.

[0127] In an exemplary embodiment, when the splicing areas of the plurality of channels include: a first splicing area and a second splicing area located at an edge and at least one third splicing area located between the first splicing area and the second splicing area, the above-mentioned determining the vertical layering characteristic value according to the second distance characteristic value corresponding to the adjacent channels that meet the preset requirements includes the following S30-S32:

[0128] S30: Determine a first reference vertical layering characteristic value according to the second distance characteristic value corresponding to the adjacent channels of the first stitching area and the second distance characteristic value corresponding to the adjacent channels of the second stitching area among the adjacent channels that meet the preset requirement.

[0129] The first splicing area and the second splicing area may be a splicing area located at the left edge and a splicing area located at the right edge, respectively. Figure 5 , the stitching area at the left edge is stitching area 1, and the stitching area at the right edge is stitching area 4. That is to say, the first stitching area and the second stitching area at the edge can be stitching area 1 and stitching area 4 respectively, and at least one third stitching area between the first stitching area and the second stitching area includes stitching area 2 and stitching area 3.

[0130] Assumptions Figure 5 The four groups of adjacent channels in are all adjacent channels that meet the preset requirements. The second distance eigenvalue corresponding to the adjacent channels (channels 1 and 2) in the first stitching area is recorded as Ground12, and the second distance eigenvalue corresponding to the adjacent channels (channels 4 and 5) in the second stitching area is recorded as Ground45. Then the first reference vertical layered eigenvalue Edge_Dif can be calculated by the following formula: Edge_Dif = Ground12-Ground45.

[0131] S31: Determine a second reference vertical layering characteristic value according to a second distance characteristic value corresponding to at least one adjacent channel of the third stitching area among adjacent channels that meet a preset requirement.

[0132] by Figure 5 For example, assuming that at least one third stitching area in the adjacent channels that meet the preset requirements includes stitching area 2 and stitching area 3. The second distance eigenvalue corresponding to the adjacent channels (channels 2 and 3) of stitching area 2 is recorded as Ground23, and the second distance eigenvalue corresponding to the adjacent channels (channels 3 and 4) of stitching area 3 is recorded as Ground34, then the second reference vertical layered eigenvalue Center_Dif can be calculated by the following formula: Center_Dif = Ground23-Ground34.

[0133] S32: Determine a vertical layer feature value according to the first reference vertical layer feature value and the second reference vertical layer feature value.

[0134] Optionally, an average value of the first reference vertical layered characteristic value and the second reference vertical layered characteristic value may be calculated, and the calculated average value may be used as the vertical layered characteristic value.

[0135] In an exemplary embodiment, the implementation method of S32 may include: calculating the vertical stratification characteristic value based on the first reference vertical stratification characteristic value, the first weight corresponding to the first reference vertical stratification characteristic value, the second reference vertical stratification characteristic value, the second weight corresponding to the second reference vertical stratification characteristic value, the second distance characteristic value corresponding to the adjacent channel of the first stitching area, the third weight corresponding to the first stitching area, the second distance characteristic value corresponding to the adjacent channel of the second stitching area, and the fourth weight corresponding to the second stitching area; wherein the first weight is greater than the second weight, the second weight is greater than the third weight, and the second weight is greater than the fourth weight.

[0136] Assume that the first weight, the second weight, the third weight, and the fourth weight are recorded as a1, a2, a3, and a4 respectively. Figure 5 As can be seen from the marking of different parameter values ​​in the above text, the implementation of S32 can be expressed as: according to the first reference vertical layer characteristic value Edge_Dif, a1, the second reference vertical layer characteristic value Center_Dif, a2, Ground12, a3, Ground45, a4, the vertical layer characteristic value is calculated. Specifically, the vertical layer characteristic value GroundScore can be calculated according to the following formula:

[0137] GroundScore=[a1*fabs(Edge_Dif)+a2*fabs(Center_Dif)+a3*fabs(Ground12)+a4*

[0138] fabs(Ground45)] / (a1+a2+a3+a4); where fabs is the absolute value of a floating point number. Optionally, a1=20, a2=4, a3=1, a4=1.

[0139] In this embodiment, a larger weight is set for the first reference vertical stratification eigenvalue, and the first reference vertical stratification eigenvalue is amplified by a larger multiple, that is, the first reference vertical stratification eigenvalue is calculated by amplifying the edge-based stitching area. Since the edge stitching area has a relatively large degree of distortion compared to the middle stitching area, that is, the degree of stratification may be large, setting a larger weight can reasonably amplify the first reference vertical stratification eigenvalue corresponding to the edge stitching area, making the degree of stratification of the edge stitching area more obvious. By combining different weights and eigenvalues ​​such as Edge_Dif, Center_Dif, Ground12, and Ground45, the vertical stratification degree of each stitching area in multiple channels can be comprehensively considered, which is conducive to the accurate and reasonable calculation of the vertical stratification eigenvalue.

[0140] Exemplarily, if the stitching area of ​​multiple channels includes: two stitching areas symmetrically distributed relative to the center, the second distance characteristic values ​​corresponding to adjacent channels of the two stitching areas can be calculated respectively, and then the two calculated second distance characteristic values ​​are averaged to obtain an average value, and the average value is used as the vertical layered characteristic value.

[0141] In an exemplary embodiment, the adjustment coefficients include: a first adjustment coefficient for the horizontal field of view and a second adjustment coefficient for the vertical field of view. The first adjustment coefficient is used to adjust the horizontal field of view of the galvanometer, and the second adjustment coefficient is used to adjust the vertical field of view of the galvanometer. The implementation of step 4033 may include: for each reference coefficient, determining the horizontal layered characteristic value and the vertical layered characteristic value of the splicing area under the action of the reference coefficient. Correspondingly, the implementation of step 4034 may include: according to the horizontal layered characteristic value of the splicing area under the action of each reference coefficient, selecting the reference coefficient that minimizes the horizontal layered characteristic value of the splicing area from multiple reference coefficients as the first adjustment coefficient. According to the vertical layered characteristic value of the splicing area under the action of each reference coefficient, selecting the reference coefficient that minimizes the vertical layered characteristic value of the splicing area from multiple reference coefficients as the second adjustment coefficient. Among them, for each reference coefficient, the implementation of determining the horizontal layered characteristic value and the vertical layered characteristic value of the splicing area under the action of the reference coefficient may include the following S41-S48:

[0142] S41: Determine a first reference normal vector according to the reference coefficient and the actual normal vector; wherein the azimuth component of the first reference normal vector is the product of the reference coefficient and the azimuth component of the actual normal vector, and the pitch component of the first reference normal vector is the same as the pitch component of the actual normal vector.

[0143] For example, the reference coefficient is recorded as a1, the actual normal vector is recorded as (pitch1, yaw1), and the first reference normal vector can be (a1*pitch1, yaw1).

[0144] S42: Determine a first reference outgoing vector corresponding to each point according to the first reference normal vector and the incident vector corresponding to each point.

[0145] From the above description, it can be seen that the incident vector corresponding to each point is known. Based on the principle of light reflection, when the first reference normal vector of the galvanometer and the incident vector corresponding to each point are known, the first reference output vector after reflection by the galvanometer can be solved.

[0146] S43: Determine updated first-category points corresponding to each point according to the first reference outgoing vector corresponding to each point and the distance between each point and the origin of the galvanometer, and obtain an updated first-category point cloud.

[0147] It can be understood that the first reference outgoing vector is actually a ray. If a distance is determined on the ray, a point on the ray can be obtained, and the point on the ray is the updated point. Based on this, the updated first-class points corresponding to each point can be determined in the direction of the first reference outgoing vector corresponding to each point, and the updated first-class points form an updated first-class point cloud.

[0148] S44: Determine, according to the updated first-category point cloud, a horizontal layered characteristic value of the splicing area under the effect of the reference coefficient.

[0149] Specifically, the above describes an implementation method for determining the horizontal layered characteristic values ​​of the stitching area based on the first type of point cloud set. In this step, the implementation method for determining the horizontal layered characteristic values ​​of the stitching area described above can be referred to, and the updated first type of point cloud is used as the first type of point cloud set to recalculate the horizontal layered characteristic values ​​of the stitching area, thereby obtaining the horizontal layered characteristic values ​​of the stitching area under the action of multiple reference coefficients.

[0150] S45: Determine a second reference normal vector according to the reference coefficient and the actual normal vector; wherein the pitch angle component of the second reference normal vector is the product of the reference coefficient and the pitch angle component of the actual normal vector, and the azimuth angle component of the second reference normal vector is the same as the azimuth angle component of the actual normal vector.

[0151] For example, the reference coefficient is recorded as a1, the actual normal vector is recorded as (pitch1, yaw1), and the second reference normal vector can be (pitch1, a1*yaw1).

[0152] S46: Determine a second reference outgoing vector corresponding to each point according to the second reference normal vector and the incident vector corresponding to each point.

[0153] From the above description, it can be seen that the incident vector corresponding to each point is known. Based on the principle of light reflection, when the second reference normal vector of the galvanometer and the incident vector corresponding to each point are known, the second reference output vector after reflection by the galvanometer can be solved.

[0154] S47: Determine updated second-type points corresponding to each point according to the second reference emission vector corresponding to each point and the distance between each point and the origin of the galvanometer, and obtain an updated second-type point cloud.

[0155] It can be understood that the second reference outgoing vector is actually a ray. If a distance is determined on the ray, a point on the ray can be obtained, and the point on the ray is the updated point. Based on this, the updated second-class points corresponding to each point can be determined in the direction of the second reference outgoing vector corresponding to each point, and the updated second-class points form an updated second-class point cloud.

[0156] S48: Determine, according to the updated second type point cloud, a vertical layered characteristic value of the splicing area under the effect of the reference coefficient.

[0157] Specifically, the above describes an implementation method for determining the vertical layered characteristic values ​​of the stitching area based on the second type of point cloud set. In this step, the implementation method for determining the vertical layered characteristic values ​​of the stitching area described above can be referred to, and the updated second type of point cloud is used as the second type of point cloud set to recalculate the vertical layered characteristic values ​​of the stitching area, thereby obtaining the vertical layered characteristic values ​​of the stitching area under the action of multiple reference coefficients.

[0158] It can be seen from the above description that the corresponding horizontal stratification characteristic values ​​and vertical stratification characteristic values ​​are determined for multiple reference coefficients, so that the minimum horizontal stratification characteristic value can be selected from the multiple horizontal stratification characteristic values ​​corresponding to the multiple reference coefficients determined, and the reference coefficient corresponding to the minimum horizontal stratification characteristic value is used as the first adjustment coefficient. The minimum vertical stratification characteristic value is selected from the multiple vertical stratification characteristic values ​​corresponding to the multiple reference coefficients determined, and the reference coefficient corresponding to the minimum vertical stratification characteristic value is used as the second adjustment coefficient. It can be understood that in a specific implementation, the first adjustment coefficient and the second adjustment coefficient finally determined may be the same or different.

[0159] After obtaining the first adjustment coefficient and the second adjustment coefficient, the horizontal drive signal can be adjusted according to the first adjustment coefficient so that when the galvanometer is driven by the adjusted horizontal drive signal, the horizontal stratification characteristic value of the stitching area is less than the preset threshold value, and the vertical drive signal can be adjusted according to the second adjustment coefficient so that when the galvanometer is driven by the adjusted vertical drive signal, the vertical stratification characteristic value of the stitching area is less than the preset threshold value.

[0160] In this embodiment, the drive signal is adjusted according to the first adjustment coefficient and the second adjustment coefficient, which is equivalent to adjusting the vertical drive signal and the horizontal drive signal of the galvanometer when calibrating the galvanometer, so as to realize the correction of the vertical field of view and the horizontal field of view of the galvanometer, so that the vertical stratification characteristic value and the horizontal stratification characteristic of the stitching area can be less than the preset threshold value, so as to further make the vertical stratification degree and the horizontal stratification degree smaller, or make the vertical stratification degree and the horizontal stratification degree of the stitching area reach the minimum within a certain correction range, which is conducive to restoring the field of view of the galvanometer to the factory state or close to the factory state, thereby improving the scanning accuracy of the galvanometer.

[0161] The correction method in this embodiment only calculates the point cloud of the splicing area. The number of point clouds is small and the computing power is small. The hierarchical eigenvalues ​​can be self-iteratively calculated by obtaining the point cloud once, so as to complete the subsequent correction process based on the hierarchical eigenvalues. There is no need to obtain the point cloud in real time, and it does not interfere with the normal point cloud output. In addition, there is no fixed scene requirement during the correction process, and most of the scenes used by the radar can achieve self-correction. The radar does not need to return to the calibration site to self-correct the field of view, which is conducive to ensuring that the field of view of the radar meets the rated requirements throughout its life cycle.

[0162] Figure 7 It is a structural schematic diagram of a galvanometer correction device provided in an embodiment of the present application.

[0163] For example, Figure 7 As shown, the device includes: a point cloud acquisition module 701, which is used to acquire the point cloud of the splicing area between multiple channels of the radar. A layered characteristic value determination module 702, which is used to determine the layered characteristic value of the splicing area according to the point cloud of the splicing area; wherein the layered characteristic value is used to characterize the layering degree of the point cloud of the splicing area. An adjustment coefficient determination module 703, which is used to determine the adjustment coefficient of the drive signal of the galvanometer in the radar when the layered characteristic value is greater than a preset threshold.

[0164] The adjustment module 704 is used to adjust the driving signal according to the adjustment coefficient so that when the galvanometer is driven by the adjusted driving signal, the layered characteristic value of the splicing area is less than a preset threshold.

[0165] It is not difficult to find that this embodiment is a device embodiment corresponding to the above method embodiment, and this embodiment can be implemented in conjunction with the above method embodiment. The relevant technical details and technical effects mentioned in the above method embodiment are still valid in this embodiment, and in order to reduce repetition, they are not repeated here. Accordingly, the relevant technical details mentioned in this embodiment can also be applied in the above method embodiment.

[0166] Figure 8 It is a schematic diagram of the structure of a radar provided in an embodiment of the present application.

[0167] For example, Figure 8 As shown, the radar includes: a memory 801 and a processor 802, wherein the memory 801 stores executable program codes, and the processor 802 is used to call and execute the executable program codes to perform a galvanometer calibration method.

[0168] In this embodiment, the radar can be divided into functional modules according to the above method example. For example, each functional module can be corresponded, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0169] In the case of dividing each functional module according to each function, the radar may include: a point cloud acquisition module, a hierarchical feature value determination module, an adjustment coefficient determination module, an adjustment module, etc. It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here.

[0170] The radar provided in this embodiment is used to execute the above-mentioned galvanometer correction method, and thus can achieve the same effect as the above-mentioned implementation method.

[0171] In the case of an integrated unit, the radar may include a processing module and a storage module. The processing module may be used to control and manage the actions of the radar. The storage module may be used to support the radar in executing mutual program codes and data.

[0172] The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits represented in combination with the contents disclosed in this application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

[0173] This embodiment also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is run on a computer, the computer executes the above-mentioned related method steps to implement a galvanometer correction method in the above-mentioned embodiment.

[0174] This embodiment further provides a computer program product. When the computer program product is run on a computer, the computer is enabled to execute the above-mentioned related steps to implement a calibration method for a galvanometer in the above-mentioned embodiment.

[0175] In addition, the radar provided in the embodiments of the present application may specifically be a chip, a component or a module, and the radar may include a connected processor and a memory; wherein the memory is used to store instructions, and when the radar is running, the processor may call and execute the instructions so that the chip executes a galvanometer correction method in the above-mentioned embodiment.

[0176] Among them, the radar, computer-readable storage medium, computer program product or chip provided in this embodiment are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0177] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0178] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0179] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for calibrating a galvanometer, characterized in that: The method comprises: Obtain point clouds of the stitching areas between multiple channels of the radar; Determine, according to the point cloud of the splicing area, a stratification feature value of the splicing area; wherein the stratification feature value is used to characterize the stratification degree of the point cloud of the splicing area; When the hierarchical characteristic value is greater than a preset threshold, determining an adjustment coefficient of a driving signal for a galvanometer in the radar; The driving signal is adjusted according to the adjustment coefficient, so that when the galvanometer is driven by the adjusted driving signal, the layered characteristic value of the splicing area is less than the preset threshold.

2. The method according to claim 1, characterized in that The step of determining the hierarchical feature value of the splicing area according to the point cloud of the splicing area includes: For each to-be-matched point in the first channel of the stitching area, a target point matching the to-be-matched point is determined in the second channel of the stitching area, and a pair of matching points corresponding to each group of adjacent channels in the multiple channels is obtained; wherein one of the matching point pairs includes a to-be-matched point located in the first channel and a target point located in the second channel, the target point is a point in the second channel that is closest to the to-be-matched point, and the first channel and the second channel belong to a group of adjacent channels in the multiple channels; According to the matching point pairs corresponding to each group of adjacent channels, a distance feature value corresponding to the adjacent channels that meets the preset requirements is calculated; wherein the distance feature value is determined based on the distance between two points in the matching point pairs corresponding to each group of adjacent channels; The hierarchical characteristic value of the splicing area is determined according to the distance characteristic values ​​corresponding to the adjacent channels that meet the preset requirements.

3. The method according to claim 2, characterized in that Before calculating the distance feature values ​​corresponding to the adjacent channels that meet the preset requirements according to the matching point pairs corresponding to the groups of adjacent channels, the method further includes: Determine the number of matching point pairs corresponding to each group of adjacent channels; The adjacent channels whose number of matching point pairs is greater than a preset number threshold are determined as the adjacent channels that meet the preset requirements.

4. The method according to claim 2, characterized in that: The step of determining, for each to-be-matched point in the first channel of the stitching area, a target point that matches the to-be-matched point in the second channel of the stitching area comprises: For each to-be-matched point in the first channel of the stitching area, determining a search range corresponding to the to-be-matched point; Within the search range corresponding to the point to be matched, a target point in the second channel of the stitching area that matches the point to be matched is determined.

5. The method according to claim 4, characterized in that For each to-be-matched point in the first channel of the stitching area, determining a search range corresponding to the to-be-matched point includes: Determine the polar coordinates and / or spatial coordinates of the points to be matched; Determine a search range corresponding to the point to be matched according to the polar coordinates and / or spatial coordinates; Among them, the spatial distance between each point in the search range and the point to be matched is less than a preset distance threshold, and / or the azimuth deviation between each point in the search range and the point to be matched is less than a preset azimuth threshold and the pitch angle deviation is less than a preset pitch angle threshold.

6. The method according to claim 5, characterized in that The spatial distance between each point in the search range and the point to be matched is less than a preset distance threshold corresponding to each point, and the preset distance threshold corresponding to each point is determined based on the spatial distance between each point in the search range and the point to be matched and a preset angle.

7. The method according to any one of claims 2 to 6, characterized in that: The hierarchical feature values ​​include horizontal hierarchical feature values ​​and vertical hierarchical feature values; for each to-be-matched point in the first channel of the stitching area, determining a target point that matches the to-be-matched point in the second channel of the stitching area, and obtaining a pair of matching points corresponding to each group of adjacent channels in the multiple channels, comprises: According to the point cloud in the first channel of the stitching area, a first type of point cloud set and a second type of point cloud set are screened out; wherein the angle between the line between any two adjacent points in the first type of point cloud set and the Z axis is less than a first preset angle, and the angle between the line between any two adjacent points in the second type of point cloud set and the X axis is less than a second preset angle; For each first-category point to be matched in the first-category point cloud set, a first target point matching the first-category point to be matched is determined in the second channel of the stitching area, and a first-category matching point pair corresponding to each group of adjacent channels in the multiple channels is obtained; wherein a first-category matching point pair includes a first-category point to be matched located in the first channel and a first target point located in the second channel, and the first target point is a point in the second channel that is closest to the first-category point to be matched; For each second-class point to be matched in the second-class point cloud set, a second target point matching the second-class point to be matched is determined in the second channel of the stitching area, and a second-class matching point pair corresponding to each group of adjacent channels in the multiple channels is obtained; wherein a second-class matching point pair includes a second-class point to be matched located in the first channel and a second target point located in the second channel, and the second target point is a point in the second channel that is closest to the second-class point to be matched; The step of calculating the distance feature values ​​corresponding to the adjacent channels that meet the preset requirements according to the matching point pairs corresponding to the groups of adjacent channels includes: Calculate the first distance feature value corresponding to the adjacent channels that meet the preset requirements according to the first type matching point pairs corresponding to each group of adjacent channels; Calculating second distance feature values ​​corresponding to adjacent channels that meet preset requirements according to the second type matching point pairs corresponding to each group of adjacent channels; The step of determining the hierarchical characteristic value of the splicing area according to the distance characteristic values ​​corresponding to the adjacent channels that meet the preset requirements includes: Determining the horizontal layering characteristic value according to the first distance characteristic value corresponding to the adjacent channels that meet the preset requirements; The vertical stratification characteristic value is determined according to the second distance characteristic values ​​corresponding to the adjacent channels that meet the preset requirements.

8. The method according to claim 7, characterized in that The determining the horizontal layering characteristic value according to the first distance characteristic value corresponding to the adjacent channels that meet the preset requirements includes: Sum the first distance eigenvalues ​​corresponding to adjacent channels that meet preset requirements to obtain a sum of the first distance eigenvalues; The horizontal layering characteristic value is determined according to the sum of the first distance characteristic values ​​and the number of groups of adjacent channels that meet preset requirements.

9. The method according to claim 7, characterized in that: In a case where the stitching areas of the plurality of channels include: a first stitching area and a second stitching area located at an edge and at least one third stitching area located between the first stitching area and the second stitching area, determining the vertical layering characteristic value according to the second distance characteristic values ​​corresponding to the adjacent channels that meet the preset requirements includes: Determine a first reference vertical layering characteristic value according to the second distance characteristic value corresponding to the adjacent channels of the first stitching area and the second distance characteristic value corresponding to the adjacent channels of the second stitching area among the adjacent channels that meet the preset requirements; Determine a second reference vertical layering characteristic value according to a second distance characteristic value corresponding to at least one adjacent channel of the third stitching area among the adjacent channels that meet the preset requirements; A vertical layer feature value is determined according to the first reference vertical layer feature value and the second reference vertical layer feature value.

10. The method according to claim 9, characterized in that The determining of the vertical layer characteristic value according to the first reference vertical layer characteristic value and the second reference vertical layer characteristic value comprises: Calculate a vertical layered feature value according to the first reference vertical layered feature value, the first weight corresponding to the first reference vertical layered feature value, the second reference vertical layered feature value, the second weight corresponding to the second reference vertical layered feature value, the second distance feature value corresponding to the adjacent channel of the first stitching area, the third weight corresponding to the first stitching area, the second distance feature value corresponding to the adjacent channel of the second stitching area, and the fourth weight corresponding to the second stitching area; Among them, the first weight is greater than the second weight, the second weight is greater than the third weight, and the second weight is greater than the fourth weight.

11. The method according to any one of claims 1 to 6, characterized in that: The step of determining the adjustment coefficient of the driving signal of the galvanometer in the radar comprises: Calculating the actual normal vector of the galvanometer according to the spatial coordinates of each point in the point cloud of the stitching area and the incident vector corresponding to each point; Determining a plurality of reference coefficients within a preset reference coefficient range with a preset step value; For each of the reference coefficients, determining a hierarchical characteristic value of the splicing area under the effect of the reference coefficient; According to the hierarchical characteristic value of the splicing area under the effect of each of the reference coefficients, a reference coefficient that minimizes the hierarchical characteristic value of the splicing area is selected from the multiple reference coefficients as the adjustment coefficient; Wherein, the determining of the hierarchical characteristic value of the splicing area under the effect of the reference coefficient includes: Taking the product of the reference coefficient and the actual normal vector as a reference normal vector; Determine a reference outgoing vector corresponding to each point according to the reference normal vector and the incident vector corresponding to each point; Determine updated points corresponding to the respective points according to reference emission vectors corresponding to the respective points and distances between the respective points and the origin of the galvanometer, and obtain updated point clouds; According to the updated point cloud, a hierarchical characteristic value of the splicing area under the effect of the reference coefficient is determined.

12. The method according to claim 11, characterized in that The adjustment coefficients include: a first adjustment coefficient for the horizontal field of view and a second adjustment coefficient for the vertical field of view; The step of determining, for each of the reference coefficients, a hierarchical characteristic value of the splicing area under the effect of the reference coefficient comprises: For each of the reference coefficients, determining a horizontal layer characteristic value and a vertical layer characteristic value of the splicing area under the effect of the reference coefficient; The step of selecting, according to the hierarchical characteristic value of the splicing area under the action of each reference coefficient, a reference coefficient that minimizes the hierarchical characteristic value of the splicing area from among the multiple reference coefficients as the adjustment coefficient comprises: According to the horizontal layered characteristic value of the splicing area under the effect of each of the reference coefficients, a reference coefficient that minimizes the horizontal layered characteristic value of the splicing area is selected from the multiple reference coefficients as the first adjustment coefficient; According to the vertical layered characteristic value of the splicing area under the effect of each of the reference coefficients, a reference coefficient that minimizes the vertical layered characteristic value of the splicing area is selected from the multiple reference coefficients as the second adjustment coefficient; The determining of the horizontal layer characteristic value and the vertical layer characteristic value of the splicing area under the effect of the reference coefficient includes: Determine a first reference normal vector according to the reference coefficient and the actual normal vector; wherein the azimuth component of the first reference normal vector is the product of the reference coefficient and the azimuth component of the actual normal vector, and the elevation component of the first reference normal vector is the same as the elevation component of the actual normal vector; Determine a first reference outgoing vector corresponding to each point according to the first reference normal vector and the incident vector corresponding to each point; Determine updated first-category points corresponding to each point according to the first reference outgoing vector corresponding to each point and the distance between each point and the origin of the galvanometer, and obtain an updated first-category point cloud; Determining, according to the updated first-category point cloud, a horizontal hierarchical characteristic value of the splicing area under the effect of the reference coefficient; Determine a second reference normal vector according to the reference coefficient and the actual normal vector; wherein the pitch angle component of the second reference normal vector is the product of the reference coefficient and the pitch angle component of the actual normal vector, and the azimuth angle component of the second reference normal vector is the same as the azimuth angle component of the actual normal vector; Determine a second reference outgoing vector corresponding to each point according to the second reference normal vector and the incident vector corresponding to each point; Determine updated second-type points corresponding to each point according to the second reference outgoing vector corresponding to each point and the distance between each point and the origin of the galvanometer, and obtain an updated second-type point cloud; According to the updated second type point cloud, a vertical layered characteristic value of the splicing area under the effect of the reference coefficient is determined.

13. A calibrating device for a galvanometer, characterized in that: The device comprises: A point cloud acquisition module is used to obtain point clouds of the stitching area between multiple channels of the radar; A layered feature value determination module, used to determine the layered feature value of the splicing area according to the point cloud of the splicing area; wherein the layered feature value is used to characterize the layered degree of the point cloud of the splicing area; An adjustment coefficient determination module, used to determine the adjustment coefficient of the driving signal of the galvanometer in the radar when the layered characteristic value is greater than a preset threshold; The adjustment module is used to adjust the driving signal according to the adjustment coefficient so that when the galvanometer is driven by the adjusted driving signal, the layered characteristic value of the splicing area is less than a preset threshold.

14. A radar, characterized in that: The radar comprises: A memory for storing executable program codes; A processor, configured to call and run the executable program code from the memory, so that the radar executes the method according to any one of claims 1 to 12.

15. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed, the method according to any one of claims 1 to 12 is implemented.

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