Method and system for testing pitch angle of laser radar

Abstract

The invention relates to the technical field of laser radar testing, and particularly discloses a laser radar pitch angle testing method and system, and the method comprises the steps: controlling a rotating platform which is provided with a laser radar to rotate in a horizontal direction, controlling the laser radar to emit a laser beam to a background plate, and controlling a camera to collect an original image of the background plate; identifying a light spot center and a pitch angle range identifier from the original image; judging whether the center of the light spot is within the range identified by the pitch angle range identifier or not; if yes, determining that the pitch angle of the laser radar is qualified; and if not, determining that the pitch angle of the laser radar is unqualified, so that after the laser radar is mounted on the rotating table, the laser radar is automatically controlled to rotate and emit a laser beam to form a light spot on the background plate, and the center of the light spot and a pitch angle range identifier are identified through an image. And whether the pitch angle is qualified is determined by judging whether the light spot center is within the pitch angle range identifier, so that the pitch angle of the laser radar can be quickly and accurately detected, manual judgment is not needed, and the automation degree is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser radar testing, and in particular relates to a laser radar pitch angle testing method and system. Background Art

[0002] LiDAR calculates the distance and angle of obstacles through the time difference between emitting and receiving the same laser beam and the speed of light in the air. If the laser angle of the LiDAR is offset downward by an angle, after hitting the ground farther away, the LiDAR will mistakenly judge the ground as an obstacle. In addition, the angle deviation of the LiDAR will misjudge the height of the obstacle, such as identifying the ground as an obstacle, and identifying the ground that can be passed smoothly as an impassable high obstacle. In other words, the pitch angle accuracy of the LiDAR directly affects the accuracy of the LiDAR and the reliability of 3D modeling. Therefore, how to test the pitch angle of the LiDAR is a technical problem that needs to be solved urgently. Summary of the invention

[0003] The purpose of the embodiments of the present invention is to provide a laser radar pitch angle testing method and system, aiming to automatically, quickly and accurately test the pitch angle of the laser radar.

[0004] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions: A laser radar pitch angle test method is applied to a laser radar pitch angle test system, wherein the laser radar pitch angle test system includes a console, a camera, a background plate, and a rotating table for installing the laser radar, and specifically includes the following steps: Controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and controlling the laser radar to emit a laser beam to a background plate, wherein the background plate is provided with a pitch angle range mark; Controlling a camera to collect an original image of the background plate, wherein the original image includes a light spot formed by the laser beam in the background plate and the pitch angle range mark; Identifying the center of the light spot and the elevation angle range mark from the original image; Determining whether the center of the light spot is within the range marked by the pitch angle range mark; If so, determining that the pitch angle of the laser radar is qualified; If not, it is determined that the pitch angle of the laser radar is unqualified.

[0005] As a further technical solution of an embodiment of the present invention, before controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, the following steps are specifically included: The rotating stage is adjusted horizontally, and the parameters of the camera are adjusted.

[0006] As a further technical solution of an embodiment of the present invention, adjusting the parameters of the camera specifically includes the following steps: Determine a scanning frame rate of the laser radar, and determine an exposure time based on the scanning frame rate; Initialize the exposure time of the camera to be equal to the basic exposure time; Adjusting the gain of the camera based on the exposure time to obtain a target exposure time and a target gain of the camera, wherein an image captured by the camera when the camera is exposed at the target exposure time and gained at the target gain satisfies a preset condition; A critical point of the camera is determined according to the target gain.

[0007] As a further technical solution of an embodiment of the present invention, controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction and controlling the laser radar to emit a laser beam to the background plate specifically includes the following steps: Controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and detecting the rotation angle of the rotating platform; When the rotation angle reaches a preset angle, the laser radar is controlled to emit a laser beam toward the background plate, forming a light spot on the background plate at the position of the preset angle.

[0008] As a further technical solution of an embodiment of the present invention, the background plate includes an upper angle limit target and a lower angle limit target of preset colors, and identifying the center of the light spot and the pitch angle range mark from the original image specifically includes the following steps: Identifying and capturing a target image including the angle upper limit target and the angle lower limit target from the original image; Determine the upper angle target and the lower angle target from the target image, and calculate the center Y of the upper angle target max and the lower limit of the angle, the center Y of the target min ; Determine a pixel area formed by pixel points whose grayscale values ​​are greater than a preset critical value from the target image, and generate a minimum circumscribed matrix of the pixel area as a light spot area; The center Y of the light spot is calculated based on the pixel values ​​of the pixel points in the light spot area. op .

[0009] As a further technical solution of the embodiment of the present invention, the center Y of the light spot is calculated based on the pixel values ​​of the pixel points in the light spot area. op Previously, the specific steps included: Calculating the ratio of the number of pixels of the light spot in the light spot area to the total number of pixels of the light spot area; Determining whether the ratio is greater than a preset threshold; If yes, calculate the spot center Y based on the pixel values ​​of the pixel points in the spot area op Steps; If not, return to the step of controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and controlling the laser radar to emit a laser beam to the background plate.

[0010] As a further technical solution of the embodiment of the present invention, the center Y of the light spot is calculated based on the pixel values ​​of the pixel points in the light spot area. op , specifically including the following steps: The pixel type value of each pixel point in the light spot area is determined in the following manner: ; The total gray value of the light spot in the yth row in the light spot area is calculated by the following formula : ; The center Y of the spot area is calculated by the following formula op : ; in, It represents the gray value of the pixel with coordinates x and y in the target image, w is the total number of rows of pixels in the spot area, and L is the total number of columns of pixels in the spot.

[0011] As a further technical solution of the embodiment of the present invention, the following steps are specifically included: Based on the spot center Y op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min And the pitch angle of the laser radar is calculated based on the preset distance between the laser radar and the background plate.

[0012] As a further technical solution of the embodiment of the present invention, a scale is also provided on the background plate. op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min After the laser radar reaches the preset distance of the background plate and calculates the pitch angle of the laser radar, the method specifically includes the following steps: The center Y of the light spot is measured by reading the scale in the target image. op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min Make corrections; The preset distance from the laser radar to the background plate and the corrected spot center Y op, the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min Calculate the elevation angle of the laser radar.

[0013] A laser radar pitch angle test system includes a control console, a camera, a background plate, and a rotating table for installing the laser radar, and specifically also includes the following units: A rotating platform and a laser radar control unit, used to control the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and to control the laser radar to emit a laser beam to a background plate, wherein the background plate is provided with a pitch angle range mark; An image acquisition control unit, used for controlling the camera to acquire an original image of the background plate, wherein the original image includes a light spot formed by the laser beam in the background plate and the pitch angle range mark; An image recognition unit, used to recognize the center of the light spot and the pitch angle range mark from the original image; A pitch angle judgment unit, used to judge whether the center of the light spot is within the range marked by the pitch angle range mark, and if so, execute the qualified determination unit, and if not, execute the unqualified determination unit; A qualified determination unit, used for determining whether the pitch angle of the laser radar is qualified; The unqualified determination unit is used to determine whether the pitch angle of the laser radar is unqualified.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The laser radar pitch angle test system of the present invention comprises a control console, a camera, a background plate and a rotating table for installing the laser radar, and the background plate is provided with a pitch angle range mark. By controlling the rotating table for installing the laser radar to rotate in the horizontal direction, and controlling the laser radar to emit a laser beam to the background plate, the camera is controlled to collect an original image of the background plate, and a light spot center and a pitch angle range mark are identified from the original image; it is judged whether the light spot center is within the range identified by the pitch angle range mark; if so, it is determined that the pitch angle of the laser radar is qualified; if not, it is determined that the pitch angle of the laser radar is unqualified. After the laser radar is installed on the rotating table, a light spot is formed on the background plate by automatically controlling the laser radar to rotate and emit a laser beam, the light spot center and the pitch angle range mark are identified by image, and it is judged whether the light spot center is within the pitch angle range mark to determine whether the pitch angle is qualified. The pitch angle of the laser radar can be detected quickly and accurately without manual judgment, and the degree of automation is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention.

[0016] Figure 1 A flowchart of a laser radar elevation angle testing method provided by an embodiment of the present invention is shown.

[0017] Figure 2 is a top view of a scene of a laser radar pitch angle test according to an embodiment of the present invention; Figure 3 is a side view of a scene of a laser radar pitch angle test according to an embodiment of the present invention; Figure 4 It is a schematic diagram of extracting a target image from an original image; Figure 5 It is a schematic diagram of calibration using a ruler; Figure 6 An application architecture diagram of a laser radar pitch angle test system provided by an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] Figure 1 The flowchart of the laser radar pitch angle test method provided by the embodiment of the present invention is shown. Specifically, the laser radar pitch angle test method of the embodiment of the present invention specifically includes the following steps: Step S101, controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and controlling the laser radar to emit a laser beam to a background plate, where a pitch angle range mark is provided.

[0020] like Figure 2 and Figure 3 As shown, in this embodiment, the hardware equipment of the laser radar pitch angle test system may include a camera, a rotating table, a control console and a background plate, wherein the laser radar to be tested can be installed on the rotating table, and a pitch angle range mark is set on the background plate, such as Figure 3 As shown, the pitch angle range mark may include an upper angle mark A and a lower angle mark B. The laser radar center O and point P on the background plate are at the same horizontal line position. The laser emitted from the laser radar center O irradiates point B on the background plate to form a light spot, and the camera captures an image of the background plate.

[0021] The rotating table can rotate 360° in the horizontal direction to simulate the scene after the laser radar is installed on the applied device. In this embodiment, the background plate can be installed at the angle required for testing, for example, at the 0°, 90°, 180° and 270° directions of the rotating table (i.e. Figure 2A background plate is set for each of the top, bottom, left and right of the image. Of course, multiple background plates can be installed according to the test angle requirements, and this embodiment does not limit this.

[0022] In this embodiment, before performing a pitch angle test on the laser radar, the rotating stage can be adjusted horizontally and the parameters of the camera can be adjusted.

[0023] Specifically, for the horizontal adjustment of the turntable, the same background plates can be placed in multiple angle areas of the turntable and the laser radar, and the horizontal lines marked on each background plate can be aligned in a consistent manner using a spirit level or a water pipe so that the horizontal line is on the same level as the center of the laser radar on the turntable.

[0024] When the rotation angle of the motor-driven rotating table is 0°, calculate the angle of the light spot on the background board at 0°. When the rotation angle of the motor-driven rotating table is 90 degrees, calculate the angle of the light spot on the background board at 90°. Similarly, calculate the angle of the light spot on the background board at 180° and 270°. By comparing the above four angle values, the small angle deviation value of the rotating table in each direction can be determined. When the four angle values ​​are basically equal, it is determined that the rotating table has completed horizontal adjustment.

[0025] When adjusting the exposure time, gain and critical point of the camera, the scanning frame rate of the lidar can be determined first, and based on the basic exposure time of the scanning frame rate, the exposure time of the camera can be initialized to be equal to the basic exposure time. The gain of the camera can be adjusted based on the exposure time to obtain the target exposure time and target gain of the camera. When the camera is exposed with the target exposure time and gained with the target gain, the image collected meets the preset conditions, and the critical point of the camera is determined according to the target gain.

[0026] Exemplarily, the target exposure time of the camera is an integer multiple of a single frame of data obtained by scanning the laser radar. For example, the frame rate of the laser radar is 10 frames, that is, 10 frames of data are scanned within 1 second, and the time required for a single frame of data is 1000ms / 10 frames=100ms. The exposure time is an integer multiple of 100ms. When adjusting, first use an exposure time of 1 frame to expose and collect the image. If it fails, use a 2-frame time, and so on, until the collected image meets the preset quality standard. When the exposure time is determined, the gain needs to be adjusted so that the collected image is not overexposed. In an example, the overexposure standard can be: the brightness of more than one ten-thousandth of the pixels in the image reaches the maximum brightness of 255, and the brightness of the first one thousandth of the pixels reaches a preset brightness (such as 80%-90% of the maximum brightness). Then, the spot area is identified based on the brightness segmentation. If the spot area is qualified and valid, it is determined that the current exposure time and gain are qualified, and are used as the final target exposure time and target gain, and the next exposure time adjustment (such as 2 frames or 3 frames) is entered. After the exposure time and gain are determined, the determined gain can be increased by a certain percentage (for example, 10%). If a valid light spot can still be identified, it is taken as the critical point.

[0027] In this embodiment, the rotating table is first leveled and the camera parameters are adjusted before the LiDAR test, so that the LiDAR test can be performed on a rotating table with good levelness, and good quality images can be captured by the adjusted camera, thereby reducing the error of the LiDAR pitch angle test and improving the accuracy of the LiDAR pitch angle test.

[0028] In this embodiment, after the rotating table is horizontally adjusted and the camera parameters are adjusted before the test, the laser radar with the pitch angle to be tested is installed on the rotating table, and the rotating table on which the laser radar is installed is controlled to rotate in the horizontal direction. The rotation angle of the rotating table is detected. When the rotation angle reaches a preset angle, the laser radar is controlled to emit a laser beam to the background board, forming a light spot on the background board at the preset angle.

[0029] Step S102, controlling the camera to collect an original image of the background plate, wherein the original image includes a light spot formed by the laser beam in the background plate and a pitch angle range mark.

[0030] Since the background plate is provided with a pitch angle range mark, the laser beam forms a light spot when irradiated on the background plate. The camera can be controlled to capture an image of the background plate as an original image, which includes the light spot and the pitch angle range mark.

[0031] Exemplarily, the rotation may be stopped when it rotates to 0°, and the laser radar is controlled to emit a laser beam toward the background plate at 0°; the rotation may be stopped when it rotates to 90°, and the laser radar is controlled to emit a laser beam toward the background plate at 90°, and so on. Each time the laser radar is rotated to a preset angle, the laser radar is controlled to emit a laser beam toward the background plate at the corresponding orientation to form a light spot on the background plate. The pitch angle of the laser radar at different rotation angles can be tested, and the pitch angle tested at each angle is more accurate.

[0032] Of course, in another example, the camera can be controlled to continuously capture images when the rotating stage rotates, and the pitch angle of the laser radar can be determined by the captured images. The acquisition speed is fast and the rotating stage does not need to stop.

[0033] like Figure 4 The following is a schematic diagram of the original image. Figure 4 It includes the upper angle limit target a, the lower angle limit target b and the light spot c, and of course also includes the image background formed by the area of ​​the background plate.

[0034] Step S103, identifying the center of the light spot and the elevation angle range mark from the original image.

[0035] In one embodiment, step S103 may specifically include the following sub-steps: Sub-step S1031 : identifying and capturing a target image including an upper angle limit target and a lower angle limit target from an original image.

[0036] like Figure 4 The figure shows that a target image including an upper angle limit target and a lower angle limit target is identified and cut out from an original image.

[0037] In one example, after the upper angle limit target and the lower angle limit target are set on the background plate, when the pitch angle standard range of the laser radar remains unchanged, the positions of the upper angle limit target and the lower angle limit target on the background plate can be fixed. When the original image of the background plate is collected, if the position of the camera relative to the background plate is fixed, the image positions of the upper angle limit target and the lower angle limit target in the original image are also fixed. The image of the specified area can be directly captured from the original image to obtain the target image including the upper angle limit target and the lower angle limit target, such as Figure 4 In the figure, the captured target image includes the upper angle limit target a, the lower angle limit target b and the light spot c.

[0038] In another example, the original image can also be input into the neural network model, and the upper angle limit target, lower angle limit target and light spot can be identified by the neural network model, and an image of the minimum circumscribed rectangular area including the upper angle limit target, lower angle limit target and light spot can be captured from the original image as the target image.

[0039] Sub-step S1032: determine the upper angle limit target and the lower angle limit target from the target image, and calculate the center Y of the upper angle limit target. max and the center Y of the lower limit target min .

[0040] In one embodiment, the upper angle limit target a and the lower angle limit target b on the background plate may be an area marked by an object of a specified color. For example, a red tape may be attached to the background plate to form the upper angle limit target a and the lower angle limit target b. The pixel values ​​of each pixel point in the target image may be traversed, and the clustering area of ​​the red pixel points may be determined by the pixel values ​​to obtain the upper angle limit target a and the lower angle limit target b in the target image, and the center area of ​​the upper angle limit target a may be calculated to obtain the center Y of the upper angle limit target. max , calculate the center area of ​​the angle lower limit target b to obtain the center Y of the angle lower limit target min .

[0041] It should be noted that the upper angle limit target a and the lower angle limit target b may be regular rectangular areas, and the centers of the upper angle limit target a and the lower angle limit target b may be the centers of the rectangles.

[0042] Sub-step S1033: determine a pixel area formed by pixel points whose grayscale values ​​are greater than a preset critical value from the target image, and generate a minimum circumscribed matrix of the pixel area as the light spot area.

[0043] In one embodiment, the pixels in the target image whose grayscale values ​​are less than a preset critical value can be first determined as pixels of the background plate, and the pixels of the background plate can be converted to black. The pixels whose grayscale values ​​are greater than the critical value can be determined as pixels of the light spot, and the pixel values ​​of the pixels of the light spot can be saved so that the color of the light spot remains unchanged, thereby determining the clustering area of ​​the pixels of the light spot, and taking a minimum circumscribed rectangle including all the pixels of the light spot as the light spot area.

[0044] Furthermore, after determining the light spot area, the ratio of the number of pixels of the light spot in the light spot area to the total number of pixels in the light spot area can be calculated to determine whether the ratio is greater than a preset threshold (for example, 80%). If so, it means that the light spot is relatively full, and the light spot area is determined to be valid. Sub-step S1034 can be executed. If not, it means that the light spot is invalid, and it is necessary to return to step S101 and continue to collect the original image.

[0045] Of course, the length L and width W of the spot area can also be limited. For example, the length L needs to be greater than the minimum number of columns and less than the maximum number of columns, and the width W needs to be greater than the minimum number of rows and less than the maximum number of rows. If the requirements for the length L and the width W are not met, it means that the spot is too small or too large, and the spot is also determined to be invalid.

[0046] In this embodiment, after determining the light spot area but before calculating the center of the light spot, whether the light spot is valid is determined by the length and width of the light spot area, and the ratio of the number of pixels of the light spot in the light spot area to the total number of pixels of the light spot area. A high-quality light spot can be determined to test the pitch angle of the laser radar through the high-quality light spot, thereby improving the accuracy of the laser radar pitch angle test.

[0047] Sub-step S1034: Calculate the spot center Y based on the pixel values ​​of the pixel points in the spot area op .

[0048] Specifically, the pixel type value of each pixel point in the spot area can be determined in the following manner: ; The total gray value of the light spot in the yth row in the light spot area is calculated by the following formula : ; The center Y of the spot area is calculated by the following formula op : ; in, It represents the gray value of the pixel with coordinates x and y in the target image, w is the total number of rows of pixels in the spot area, and L is the total number of columns of pixels in the spot.

[0049] This embodiment calculates the neutrality of the spot area through the pixel type value and the grayscale value of each pixel point in the spot area. Compared with directly taking the geometric center of the spot area, the center of the spot area calculated by this embodiment is closer to the center of the gathering area of ​​the pixel points of the spot and is more accurate.

[0050] Step S104, determining whether the center of the light spot is within the range marked by the pitch angle range mark.

[0051] Specifically, we can determine Y min ≤Y op ≤Y max If yes, execute S105, if no, execute S106.

[0052] Step S105, determine whether the pitch angle of the laser radar is qualified.

[0053] If the center of the light spot Y op Meet Y min ≤Y op ≤Y max , determine that the pitch angle of the laser radar is qualified, the pitch angle test of the laser radar at this rotation angle is completed, and continue to test the pitch angle at the next rotation angle.

[0054] Step S106, determining that the pitch angle of the laser radar is unqualified.

[0055] If the center of the light spot Y op Does not meet Y min ≤Y op ≤Y max , it is determined that the pitch angle of the laser radar is unqualified, the pitch angle test of the laser radar at this rotation angle is completed, and the pitch angle test at the next rotation angle continues.

[0056] In another embodiment, the specific pitch angle value of the laser radar can also be calculated. Specifically, it can be based on the spot center Y op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y min And the preset distance from the laser radar to the background plate is used to calculate the pitch angle of the laser radar.

[0057] Specifically, Figure 3 The side view shown, combined with the trigonometric function relationship, can be used to calculate the pitch angle of the lidar by the following formula: ∠POC = arctan(PC / OP); in, PC = PB + (PA-PB) × (Y op -Y min ) / (Y max -Y min ); Furthermore, when the distance between the camera and the background is small, the image captured by the camera is severely distorted and needs to be corrected, such as Figure 5 As shown in the figure, a scale can be set on the background plate. After the original image is acquired, the scale is also in the image. The center Y of the light spot can be measured by reading the scale in the target image. op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y min Calibrate the laser radar to the background plate and the center Y of the calibrated spot. op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y min Calculate the pitch angle of the lidar.

[0058] For example, when determining the center Y of the light spot op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y min After that, the spot center Y op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y minThe number of rows of pixels is horizontally aligned to the scale, and the center Y of the light spot is read from the scale. op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y min Corresponding to the reading, substitute the corrected reading into the PC calculation formula to obtain the accurate PC and then recalculate the pitch angle ∠POC.

[0059] The laser radar pitch angle test system of the present invention comprises a control console, a camera, a background plate and a rotating table for installing the laser radar, and the background plate is provided with a pitch angle range mark. By controlling the rotating table for installing the laser radar to rotate in the horizontal direction, and controlling the laser radar to emit a laser beam to the background plate, the camera is controlled to collect an original image of the background plate, and a light spot center and a pitch angle range mark are identified from the original image; it is judged whether the light spot center is within the range identified by the pitch angle range mark; if so, it is determined that the pitch angle of the laser radar is qualified; if not, it is determined that the pitch angle of the laser radar is unqualified. After the laser radar is installed on the rotating table, a light spot is formed on the background plate by automatically controlling the laser radar to rotate and emit a laser beam, the light spot center and the pitch angle range mark are identified by image, and it is judged whether the light spot center is within the pitch angle range mark to determine whether the pitch angle is qualified. The pitch angle of the laser radar can be detected quickly and accurately without manual judgment, and the degree of automation is high.

[0060] Furthermore, a scale can be used to calibrate the center Y of the light spot. op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y min , and based on the spot center Y op 、The center Y of the angle upper limit target max 、The center of the lower limit angle target Y min The pitch angle of the laser radar is calculated based on the preset distance between the laser radar and the background plate, and the precise pitch angle of the laser radar can be calculated.

[0061] Figure 6 The application architecture diagram of the laser radar pitch angle test system provided by an embodiment of the present invention is shown. The laser radar pitch angle test system of this embodiment includes a console, a camera, a background plate, and a rotating table for installing the laser radar, and specifically also includes the following units: The rotating platform and laser radar control unit 601 is used to control the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and to control the laser radar to emit a laser beam to a background plate, where a pitch angle range mark is provided; An image acquisition control unit 602, used for controlling the camera to acquire an original image of the background plate, wherein the original image includes a light spot formed by the laser beam in the background plate and the pitch angle range mark; An image recognition unit 603 is used to recognize the center of the light spot and the pitch angle range mark from the original image; A pitch angle determination unit 604, configured to determine whether the center of the light spot is within the range identified by the pitch angle range identifier, and if so, execute a qualified determination unit 605, and if not, execute an unqualified determination unit 606; A qualified determination unit 605, used to determine whether the pitch angle of the laser radar is qualified; The unqualified determination unit 606 is used to determine whether the pitch angle of the laser radar is unqualified.

[0062] As a further technical solution of the embodiment of the present invention, the following units are specifically included: The rotating stage and the camera adjustment unit are used to perform horizontal adjustment on the rotating stage and adjust the parameters of the camera.

[0063] As a further technical solution of the embodiment of the present invention, the rotating stage and the camera adjustment unit specifically include the following modules: A basic exposure time determination module, used to determine a scanning frame rate of the laser radar and a basic exposure time according to the scanning frame rate; An exposure time initialization module, used to initialize the exposure time of the camera to be equal to the basic exposure time; An exposure time and gain determination module, used to adjust the gain of the camera based on the exposure time to obtain a target exposure time and a target gain of the camera, wherein an image captured by the camera when the camera is exposed at the target exposure time and gained at the target gain satisfies a preset condition; A critical point determination module is used to determine the critical point of the camera according to the target gain.

[0064] As a further technical solution of the embodiment of the present invention, the rotating platform and laser radar control unit 601 specifically includes the following modules: A rotation angle detection module, used to control the rotating platform on which the laser radar is installed to rotate in the horizontal direction and detect the rotation angle of the rotating platform; The laser control module is used to control the laser radar to emit a laser beam to the background plate when the rotation angle reaches a preset angle, so as to form a light spot on the background plate at the position of the preset angle.

[0065] As a further technical solution of the embodiment of the present invention, the background plate includes an upper angle limit target and a lower angle limit target of preset colors, and the image recognition unit 603 specifically includes the following modules: A target image capture module, used to identify and capture a target image including the angle upper limit target and the angle lower limit target from the original image; The target center calculation module is used to determine the upper angle limit target and the lower angle limit target from the target image, and calculate the center Y of the upper angle limit target. max and the lower limit of the angle, the center Y of the target min ; A light spot region determination module, used to determine a pixel region formed by pixel points whose grayscale values ​​are greater than a preset critical value from the target image, and generate a minimum circumscribed matrix of the pixel region as the light spot region; The light spot center calculation module is used to calculate the light spot center Y based on the pixel values ​​of the pixel points in the light spot area. op .

[0066] As a further technical solution of the embodiment of the present invention, the image recognition unit 603 specifically further includes the following modules: A ratio calculation module, used for calculating the ratio of the number of pixels of the light spot in the light spot area to the total number of pixels of the light spot area; A ratio judgment module, used to judge whether the ratio is greater than a preset threshold value, if so, execute the spot center calculation module, if not, execute the rotating stage and laser radar control unit 601; As a further technical solution of the embodiment of the present invention, the spot center calculation module is specifically used for: The pixel type value of each pixel point in the light spot area is determined in the following manner: ; The total gray value of the light spot in the yth row in the light spot area is calculated by the following formula : ; The center Y of the spot area is calculated by the following formula op : ; in, It represents the gray value of the pixel with coordinates x and y in the target image, w is the total number of rows of pixels in the spot area, and L is the total number of columns of pixels in the spot.

[0067] As a further technical solution of the embodiment of the present invention, the following steps are specifically included: A pitch angle calculation unit is used to calculate the pitch angle based on the center Y of the light spot. op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min And the pitch angle of the laser radar is calculated based on the preset distance between the laser radar and the background plate.

[0068] As a further technical solution of the embodiment of the present invention, a scale is also provided on the background board, and after the pitch angle calculation unit, the following units are specifically included: A correction unit is used to correct the center Y of the light spot by reading the scale in the target image. op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min Make corrections; The pitch angle recalculation unit is used to use the preset distance from the laser radar to the background plate and the corrected spot center Y op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min Calculate the elevation angle of the laser radar.

[0069] It should be understood that, although each step in the flow chart of each embodiment of the present invention is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0070] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0071] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the attached claims.

[0073] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A laser radar pitch angle test method, characterized in that: Applied to a laser radar pitch angle test system, the laser radar pitch angle test system includes a console, a camera, a background plate and a rotating table for installing the laser radar, and specifically includes the following steps: Controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and controlling the laser radar to emit a laser beam to a background plate, wherein the background plate is provided with a pitch angle range mark; Controlling a camera to collect an original image of the background plate, wherein the original image includes a light spot formed by the laser beam in the background plate and the pitch angle range mark; Identifying the center of the light spot and the elevation angle range mark from the original image; Determining whether the center of the light spot is within the range marked by the pitch angle range mark; If so, determining that the pitch angle of the laser radar is qualified; If not, it is determined that the pitch angle of the laser radar is unqualified.

2. The laser radar pitch angle test method according to claim 1, characterized in that: Before controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, the following steps are specifically included: The rotating stage is adjusted horizontally, and the parameters of the camera are adjusted.

3. The laser radar pitch angle test method according to claim 2, characterized in that: Adjusting the parameters of the camera specifically includes the following steps: Determine a scanning frame rate of the laser radar, and determine an exposure time based on the scanning frame rate; Initialize the exposure time of the camera to be equal to the basic exposure time; Adjusting the gain of the camera based on the exposure time to obtain a target exposure time and a target gain of the camera, wherein an image captured by the camera when the camera is exposed at the target exposure time and gained at the target gain satisfies a preset condition; A critical point of the camera is determined according to the target gain.

4. The laser radar pitch angle test method according to claim 1, characterized in that: Controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction and controlling the laser radar to emit a laser beam to the background plate specifically includes the following steps: Controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and detecting the rotation angle of the rotating platform; When the rotation angle reaches a preset angle, the laser radar is controlled to emit a laser beam toward the background plate, forming a light spot on the background plate at the position of the preset angle.

5. The laser radar pitch angle test method according to any one of claims 1 to 4, characterized in that: The background plate includes an angle upper limit target and an angle lower limit target of preset colors, and identifying the center of the light spot and the pitch angle range mark from the original image specifically includes the following steps: Identifying and capturing a target image including the angle upper limit target and the angle lower limit target from the original image; Determine the upper angle target and the lower angle target from the target image, and calculate the center Y of the upper angle target max and the lower limit of the angle, the center Y of the target min ; Determine a pixel area formed by pixel points whose grayscale values ​​are greater than a preset critical value from the target image, and generate a minimum circumscribed matrix of the pixel area as a light spot area; The center Y of the light spot is calculated based on the pixel values ​​of the pixel points in the light spot area. op .

6. The laser radar pitch angle test method according to claim 5, characterized in that: The spot center Y is calculated based on the pixel values ​​of the pixel points in the spot area. op Previously, the specific steps included: Calculating the ratio of the number of pixels of the light spot in the light spot area to the total number of pixels of the light spot area; Determining whether the ratio is greater than a preset threshold; If yes, calculate the spot center Y based on the pixel values ​​of the pixel points in the spot area op Steps; If not, return to the step of controlling the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and controlling the laser radar to emit a laser beam to the background plate.

7. The laser radar pitch angle test method according to claim 6, characterized in that: The center Y of the light spot is calculated based on the pixel values ​​of the pixel points in the light spot area. op , specifically including the following steps: The pixel type value of each pixel point in the light spot area is determined in the following manner: ； The total gray value of the light spot in the yth row in the light spot area is calculated by the following formula : ； The center Y of the spot area is calculated by the following formula op : ； in, It represents the gray value of the pixel with coordinates x and y in the target image, w is the total number of rows of pixels in the spot area, and L is the total number of columns of pixels in the spot.

8. The laser radar pitch angle test method according to claim 5, characterized in that: The specific steps include: Based on the spot center Y op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min And the pitch angle of the laser radar is calculated based on the preset distance between the laser radar and the background plate.

9. The laser radar pitch angle test method according to claim 8, characterized in that: The background plate is also provided with a scale based on the center Y of the light spot. op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min After the laser radar reaches the preset distance of the background plate and calculates the pitch angle of the laser radar, the method specifically includes the following steps: The center Y of the light spot is measured by reading the scale in the target image. op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min Make corrections; The preset distance from the laser radar to the background plate and the corrected spot center Y op , the center Y of the angle upper limit target max , the center Y of the lower limit target of the angle min Calculate the elevation angle of the laser radar.

10. A laser radar pitch angle test system, characterized in that: It includes a control console, a camera, a background plate, and a rotating table for installing a laser radar, and specifically includes the following units: A rotating platform and a laser radar control unit, used to control the rotating platform on which the laser radar is installed to rotate in the horizontal direction, and to control the laser radar to emit a laser beam to a background plate, wherein the background plate is provided with a pitch angle range mark; An image acquisition control unit, used for controlling the camera to acquire an original image of the background plate, wherein the original image includes a light spot formed by the laser beam in the background plate and the pitch angle range mark; An image recognition unit, used to recognize the center of the light spot and the pitch angle range mark from the original image; A pitch angle judgment unit, used to judge whether the center of the light spot is within the range marked by the pitch angle range mark, and if so, execute the qualified determination unit, and if not, execute the unqualified determination unit; A qualified determination unit, used for determining whether the pitch angle of the laser radar is qualified; The unqualified determination unit is used to determine whether the pitch angle of the laser radar is unqualified.

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