LiDAR resolution testing method and system

Abstract

The present invention provides a laser radar angular resolution test method and system, which relate to the field of laser radar technology. The method comprises the following steps: obtaining the horizontal angle between the center positions of two adjacent sub-target plates in the same row and the coordinate center of the laser radar to be tested; obtaining the vertical angle between the center positions of two adjacent sub-target plates in the same column and the coordinate center of the laser radar to be tested; obtaining a frame of average point cloud frame from the collected multi-frame point cloud; for each sub-target plate, extracting the point cloud of the sub-target plate from the average point cloud frame, fitting the center of mass of the sub-target plate, and taking the point cloud closest to the center of mass as the mass point; and then, based on the horizontal angle and vertical angle of the mass point of each sub-target plate, counting the number of horizontal effective point clouds between the mass points of adjacent sub-target plates in each row and the number of vertical effective point clouds between the mass points of adjacent sub-target plates in each column, thereby calculating the angular resolution of the laser radar to be tested.

Description

Technical Field

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

[0002] LiDAR is a three-dimensional spatial perception sensor used in surveying and mapping, autonomous driving, and 3D modeling. LiDAR's angular performance, including angular resolution, determines the quality of its point cloud. Therefore, testing LiDAR's angular resolution is crucial to ensure accuracy.

[0003] Existing testing methods generally rely on observing the point cloud at the edge of the target plate. This is often affected by subjective factors and cannot guarantee test consistency. In addition, only the angular resolution of a certain row or column of point clouds can be tested each time, resulting in low efficiency and, accordingly, high testing costs. Summary of the Invention

[0004] The present invention provides a laser radar resolution testing method and system, which can improve the testing efficiency of the laser radar resolution and reduce the testing cost.

[0005] The technical solution of the present invention can be implemented as follows:

[0006] In a first aspect, the present invention provides a laser radar resolution testing method, the method comprising:

[0007] Testing is performed using an array target plate, wherein the sub-target plates of the array target plate are arranged in multiple rows in the horizontal direction and in multiple columns in the vertical direction;

[0008] Determine the center position of each sub-target plate and the coordinate center of the laser radar to be measured;

[0009] Obtain the horizontal angles between the center positions of two adjacent sub-target plates on the same row of sub-target plates and the lines connecting the coordinate center of the laser radar to be measured;

[0010] Obtain the vertical angles between the center positions of two adjacent sub-target plates in the same column and the lines connecting the coordinate center of the laser radar to be measured;

[0011] Starting the laser radar and emitting laser light to the array target plate, collecting multiple frames of point cloud, and calculating the average point cloud of the multiple frames of point cloud to obtain an average point cloud frame;

[0012] Extracting the point cloud of each sub-target plate from the average point cloud frame, and fitting the centroid of each sub-target plate;

[0013] In the average point cloud frame, the point cloud closest to the center of mass of each sub-target plate is used as the mass point of the sub-target plate;

[0014] In the average point cloud frame, according to the horizontal angle of the particle points of each sub-target plate, the number of horizontal valid point clouds between the particle points of adjacent sub-target plates in each row is counted;

[0015] In the average point cloud frame, according to the vertical angle of the particle point of each sub-target plate, the number of vertical valid point clouds between the particle points of adjacent sub-target plates in each column is counted;

[0016] Calculating the horizontal resolution of the laser radar to be tested according to the horizontal angle and the number of horizontal valid point clouds;

[0017] The vertical resolution of the laser radar to be tested is calculated based on the vertical angle and the vertical effective point cloud.

[0018] Optionally, the step of fitting the centroid of each sub-target plate includes:

[0019] The center of mass of each sub-target plate is obtained by averaging the spatial coordinates of each point cloud in the point cloud of each sub-target plate; or the center of mass of each sub-target plate is obtained by averaging the horizontal angles and / or vertical angles of each point cloud in the point cloud of each sub-target plate.

[0020] In an optional embodiment, the step of taking the point cloud closest to the center of mass of each sub-target plate in the average point cloud frame as the mass point of the sub-target plate includes:

[0021] Calculating the spatial distance between each point cloud in the point cloud of the sub-target plate and the sub-target plate's center of mass according to the spatial coordinates of each point cloud in the point cloud of the sub-target plate and the sub-target plate's center of mass, and taking the point cloud in the point cloud of the sub-target plate with the minimum spatial distance to the sub-target plate's center of mass as the sub-target plate's mass point; or

[0022] According to the horizontal angle and / or vertical angle between each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate, the angular distance between each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate is calculated, and the point cloud in the point cloud of the sub-target plate with the smallest angular distance to the center of mass of the sub-target plate is used as the mass point of the sub-target plate.

[0023] Optionally, the step of counting the number of horizontal valid point clouds between the particle points of adjacent sub-target plates in each row in the average point cloud frame according to the horizontal angle of the particle points of each sub-target plate comprises:

[0024] For any particle point of a target sub-target plate, a particle point of a sub-target plate that is located in the same row as the target sub-target plate and arranged after the target sub-target plate is taken as the first particle point;

[0025] Counting the number of point clouds that meet a first preset condition based on the horizontal angles of each point cloud located between the mass point of the target sub-target plate and the first mass point on the average point cloud frame, to obtain the number of horizontal valid point clouds between the mass point of the target sub-target plate and the first mass point;

[0026] Each of the sub-target plates is traversed to obtain the number of horizontal effective point clouds between the particles of adjacent sub-target plates in each row.

[0027] Optionally, the vertical angle of the point cloud that meets the first preset condition is in the range of [0.5*Vmin, 1.5*Vmax] or [0.8*Vmin, 1.2*Vmax] or [Vmin-Vstand, Vmax+Vstand], wherein Vmin is the smaller value of the vertical angle of the mass point of the target sub-target plate and the vertical angle of the first mass point, Vmax is the larger value of the vertical angle of the mass point of the target sub-target plate and the vertical angle of the first mass point, and Vstand is the nominal vertical angle resolution of the laser radar to be tested;

[0028] The difference between the horizontal angle of the point cloud that meets the first preset condition and the horizontal angle of other point clouds located between the particle of the target sub-target plate and the first particle on the average point cloud frame is less than a first difference value, and the first difference value is in the range of [0.5*Hstand, 1.5*Hstand], where Hstand is the nominal horizontal angle resolution of the laser radar to be tested;

[0029] If there is a point group that meets the first preset condition, any point cloud in each of the point groups is used as the horizontal valid point cloud of the point group.

[0030] Optionally, the step of counting the number of vertical valid point clouds between the particle points of adjacent sub-target plates in each column in the average point cloud frame according to the vertical angle of the particle points of each sub-target plate comprises:

[0031] For any particle point of a target sub-target plate, a particle point of a sub-target plate that is located in the same column as the target sub-target plate and arranged after the target sub-target plate is used as a second particle point;

[0032] Counting the number of point clouds that meet a second preset condition based on the vertical angles of each point cloud between the mass point of the target sub-target plate and the second mass point on the average point cloud frame, to obtain the number of vertical valid point clouds between the mass point of the target sub-target plate and the second mass point;

[0033] Each of the sub-target plates is traversed to obtain the number of vertical effective point clouds between the particles of adjacent sub-target plates in each column.

[0034] Optionally, the horizontal angle of the point cloud that meets the second preset condition is in the range of [0.5*Hmin, 1.5*Hmax] or [0.8*Hmin, 1.2*Hmax] or [Hmin-Hstand, Hmax+Hstand], wherein Hmin is the smaller value of the vertical angle of the particle of the target sub-target plate and the horizontal angle of the second particle, Hmax is the larger value of the horizontal angle of the particle of the target sub-target plate and the horizontal angle of the second particle, and Hstand is the nominal horizontal angle resolution of the laser radar to be tested;

[0035] The difference between the vertical angle of the point cloud that meets the second preset condition and the vertical angle of other point clouds located between the particle of the target sub-target plate and the second particle on the average point cloud frame is less than a second difference value, and the second difference value is in the range of [0.5*Vstand, 1.5*Vstand], where Vstand is the nominal vertical angle resolution of the laser radar to be tested;

[0036] If there is a point group that meets the second preset condition, any point cloud in each of the point groups is used as a vertical valid point cloud of the point group.

[0037] Optionally, the horizontal angle, the number of horizontal valid point clouds, and the horizontal resolution of the laser radar to be measured satisfy the following formula:

[0038]

[0039] in, is the horizontal resolution of the laser radar to be tested, is the horizontal angle, is the number of horizontal valid point clouds;

[0040] The vertical angle, the vertical effective point cloud, and the vertical resolution of the laser radar to be tested satisfy the following formula:

[0041]

[0042] in, is the vertical resolution of the laser radar to be tested, is the vertical angle, is the number of vertical valid point clouds.

[0043] Optionally, the step of starting the laser radar to emit laser light to the array target plate and collecting multiple frames of point clouds includes:

[0044] When the length of the array target plate is less than the nominal horizontal field of view angle of the laser radar to be tested, controlling the electric turntable of the laser radar to be tested to rotate left and right; or

[0045] When the width of the array target plate is smaller than the vertical field angle of the laser radar to be measured, controlling the turntable of the laser radar to be measured to rotate up and down;

[0046] By controlling the rotation of the laser radar to be tested, part of the laser energy of the laser radar to be tested that exceeds the array target plate is projected onto the array target plate, thereby obtaining a multi-frame point cloud.

[0047] In a second aspect, the present invention provides a laser radar angular resolution test system, which is used to implement the laser radar resolution test method as described in the first aspect, including a target plate, a total station, a laser radar, a fixed fixture, a two-dimensional turntable and a control device;

[0048] The laser radar is connected to the two-dimensional electric turntable through the fixing fixture;

[0049] The emission direction of the laser radar is perpendicular to the target plate;

[0050] The total station is used to measure the coordinate center position of the laser radar and the center position of each sub-target plate of the array target plate of the target plate;

[0051] The control device is connected to the laser radar data and is used to control the laser radar or read the data of the laser radar.

[0052] Optionally, the target plate includes a background plate and an array target plate, the array target plate is attached to the background plate, and the reflectivity of the array target plate is greater than that of the background plate;

[0053] The array target plate is composed of multiple sub-target plates of the same shape. The area of ​​the sub-target plates and the distance between the sub-target plates are determined by the resolution of the laser radar and the imaging distance between the laser radar and the array target plate. The horizontal distance between the sub-target plates is greater than the interval of 10 point clouds in the horizontal direction of the laser radar at the imaging distance, the vertical distance between the sub-target plates is greater than the interval of 10 point clouds in the vertical direction of the laser radar at the imaging distance, and the area of ​​the sub-target plates is greater than the area of ​​3*3 point clouds of the laser radar at the imaging distance.

[0054] Other features and advantages disclosed in the present application will be described in the following description, or some features and advantages can be inferred or determined without doubt from the description, or can be learned by implementing the above-mentioned technology disclosed in the present application.

[0055] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0057] Figure 1 A schematic diagram of the architecture of a system for testing the angular resolution of a laser radar provided by an embodiment of the present invention;

[0058] Figure 2 A schematic diagram of a flow chart of a laser radar resolution testing method provided in an embodiment of the present invention;

[0059] Figure 3 A schematic diagram of horizontal angles and vertical angles provided in an embodiment of the present invention;

[0060] Figure 4 A schematic diagram of the distribution of point clouds collected by a laser radar according to an embodiment of the present invention;

[0061] Figure 5 Schematic diagram of horizontal valid point cloud and vertical valid point cloud provided by an embodiment of the present invention.

[0062] Icons: 110-LiDAR 110; 120-Fixed fixture; 130-2D turntable; 140-Array target plate; 150-Background plate; 160-Total station; 170-Control equipment. DETAILED DESCRIPTION

[0063] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0064] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0065] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0066] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the invention is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0067] In addition, the terms "first", "second", etc., if used, are merely used to distinguish and describe, and should not be understood as indicating or implying relative importance.

[0068] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0069] In order to improve the test efficiency of laser radar resolution and reduce the test cost, the embodiment of the present invention first introduces a laser radar angle resolution test system, such as Figure 1 As shown, the system for testing the laser radar angular resolution includes a laser radar 110 , a fixture 120 , a two-dimensional electric turntable 130 , a target plate, a total station 160 and a control device 170 .

[0070] The laser radar 110 is rigidly connected to the fixing fixture 120 through screws and positioning pins.

[0071] The laser radar 110 is connected to the two-dimensional electric turntable 130 through a fixing fixture 120 . By designing the size of the fixing fixture 120 , the rotation center of the two-dimensional electric turntable 3 coincides with the coordinate center or rotation center of the laser radar 110 .

[0072] The emission direction of the laser radar 110 is perpendicular to the target plate. The target plate includes an array target plate 140 and a background plate 150 . The array target plate 140 and the background plate 150 are bonded together. The reflectivity of the array target plate 140 is greater than that of the background plate 130 .

[0073] The array target plate 140 is composed of multiple sub-target plates of the same shape. The area of ​​the sub-target plates and the distance between the sub-target plates are determined by the resolution of the laser radar and the imaging distance between the laser radar and the array target plate. The horizontal distance between the sub-target plates is greater than the interval of 10 point clouds in the horizontal direction of the laser radar at the imaging distance, the vertical distance between the sub-target plates is greater than the interval of 10 point clouds in the vertical direction of the laser radar at the imaging distance, and the area of ​​the sub-target plates is greater than the area of ​​3*3 point clouds of the laser radar at the imaging distance.

[0074] The total station is located between the laser radar 110 and the target plate, and is used to measure the coordinate center position of the laser radar 110 and the center position of each sub-target plate of the target plate array 140.

[0075] Control device 170 is data-connected to lidar 110 and includes a processor and memory. The processor executes the following lidar resolution test method by calling memory instructions or performing online debugging, calculating test results, and saving test data. The processor can be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits.

[0076] The memory is used to store the test steps of the laser radar resolution test method. The memory can be a ROM or other type of static storage device that can store static information and instructions, a RAM or other type of dynamic storage device that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc (CD-ROM) or other optical disc storage, optical disc storage (including compact disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited to this. The memory can exist independently and be connected to the processor through a communication bus. The memory can also be integrated with the processor.

[0077] based on Figure 1 The laser radar angle resolution test system shown in the figure, the embodiment of the present invention provides a laser radar resolution test method, which will be introduced in detail below.

[0078] The laser radar resolution test method uses an array target plate for testing, wherein the sub-target plates of the array target plate are arranged into multiple rows in the horizontal direction and into multiple columns in the vertical direction.

[0079] like Figure 1 As shown, the sub-target plates of the array target plate are arranged into 3 rows in the horizontal direction, and each row has 3 sub-target plates, wherein the sub-target plates marked 1, 2 and 3 are arranged in the first row, the sub-target plates marked 4, 5 and 6 are arranged in the second row, and the sub-target plates marked 7, 8 and 9 are arranged in the third row.

[0080] The sub-target plates of the array target plate are arranged into 3 columns in the vertical direction, and each column has 3 sub-target plates. The sub-target plates marked 1, 4 and 7 are arranged in the first column, the sub-target plates marked 2, 5 and 5 are arranged in the second column, and the sub-target plates marked 3, 6 and 9 are arranged in the third column.

[0081] Please refer to Figure 2 The laser radar resolution testing method includes steps S101 to S110.

[0082] S101, determine the center position of each sub-target plate and the coordinate center of the laser radar to be measured.

[0083] In the embodiment of the present invention, the center position of each sub-target plate and the coordinate center of the laser radar to be measured are measured by controlling the total station, which can be controlled by a control device or manually.

[0084] S102, obtaining the horizontal angles between the center positions of two adjacent sub-target plates on the same row of sub-target plates and the coordinate center of the laser radar to be measured.

[0085] exist Figure 1 In the test scenario shown, a total station is used to measure the horizontal angles between the center positions of sub-target plate 1 and sub-target plate 2, sub-target plate 2 and sub-target plate 3, sub-target plate 4 and sub-target plate 5, sub-target plate 5 and sub-target plate 6, sub-target plate 7 and sub-target plate 8, and sub-target plate 8 and sub-target plate 9 of the array target plate and the coordinate center of the laser radar to be measured, which is recorded as That is, the horizontal angle between the center position of the sub-target plates marked as i and j and the coordinate center of the laser radar to be measured.

[0086] like Figure 3 As shown in (a), the sub-target plates marked 1, 2 and 3 are arranged in a row. The horizontal angle between the center position of the sub-target plates marked 1 and 2 and the coordinate center of the laser radar to be measured is The horizontal angle between the center position of the sub-target plates marked 1 and 2 and the coordinate center of the laser radar to be measured is

[0087] S103, obtaining the vertical angles between the center positions of two adjacent sub-target plates in the same column and the lines connecting the coordinate center of the laser radar to be measured.

[0088] exist Figure 1 In the test scenario shown, a total station is used to measure the vertical angles between the center positions of sub-target plate 1 and sub-target plate 4, sub-target plate 4 and sub-target plate 7, sub-target plate 2 and sub-target plate 5, sub-target plate 5 and sub-target plate 8, sub-target plate 3 and sub-target plate 6, sub-target plate 6 and sub-target plate 9 of the array target plate and the coordinate center of the laser radar to be measured, which is recorded as That is, the vertical angle between the center position of the sub-target plates marked as i and j and the coordinate center of the laser radar to be measured.

[0089] like Figure 3 As shown in (b), the sub-target plates marked 1, 4 and 7 are arranged in a row. The vertical angle between the center position of the sub-target plates marked 1 and 4 and the coordinate center of the laser radar to be measured is The vertical angle between the center position of the sub-target plates marked 4 and 7 and the coordinate center of the laser radar to be measured is

[0090] S104, start the laser radar and emit laser to the array target plate, collect multiple frames of point cloud, and calculate the average point cloud of the multiple frames of point cloud to obtain a frame of average point cloud frame.

[0091] The number of collected point cloud frames must be greater than 100 frames. By averaging the spatial coordinates XYZ, horizontal angle, and vertical angle of each point in the multi-frame point cloud, an average point cloud frame is obtained.

[0092] The collected multi-frame point cloud can be Figure 4 (a) and Figure 4 The regular point cloud shown in (b) can also be Figure 4 (c) shows the irregular point cloud.

[0093] The implementation process of "starting the laser radar to be tested and emitting laser light to the array target plate to collect multi-frame point clouds" in step S104 can be as follows: when the length of the array target plate is less than the nominal horizontal field of view angle of the laser radar to be tested, the electric turntable of the laser radar to be tested is controlled to rotate left and right; or when the width of the array target plate is less than the vertical field of view angle of the laser radar to be tested, the turntable of the laser radar to be tested is controlled to rotate up and down; by controlling the rotation of the laser radar to be tested, the part of the laser light of the laser radar to be tested that exceeds the array target plate can be projected onto the array target plate to obtain multi-frame point clouds.

[0094] S105 , extracting the point cloud of each sub-target plate from the average point cloud frame, and fitting the centroid of each sub-target plate.

[0095] In the embodiment of the present invention, there are two ways to fit the centroid of the sub-target plate. One way is to obtain the centroid of each sub-target plate by averaging the spatial coordinates of each point cloud in the point cloud of each sub-target plate. The other way is to obtain the centroid of the sub-target plate by averaging the horizontal angle and / or vertical angle of each point cloud in the point cloud of each sub-target plate.

[0096] S106 , in the average point cloud frame, taking the point cloud on each sub-target plate that is closest to the center of mass of the sub-target plate as the mass point of the sub-target plate.

[0097] In an embodiment of the present invention, if the center of mass of each sub-target plate is obtained by averaging the spatial coordinates of each point cloud in the point cloud of each sub-target plate, the spatial distance between each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate can be calculated based on the spatial coordinates of each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate, and the point cloud in the point cloud of the sub-target plate with the smallest spatial distance to the center of mass of the sub-target plate is used as the mass point of the sub-target plate.

[0098] If the center of mass of each sub-target plate is obtained by averaging the horizontal angles and / or vertical angles of each point cloud in the point cloud of each sub-target plate, the angular distance between each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate (i.e., the size of the angle between the center of mass) can be calculated based on the horizontal angles and / or vertical angles of each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate, and the point cloud in the point cloud of the sub-target plate with the smallest angular distance to the center of mass of the sub-target plate is used as the mass point of the sub-target plate.

[0099] S107 , in the average point cloud frame, counting the number of horizontal valid point clouds between the particle points of adjacent sub-target plates in each row according to the horizontal angle of the particle points of each sub-target plate.

[0100] Among them, the horizontal angle of the particle is calculated through the coordinate value of the particle itself.

[0101] In a possible implementation, step S107 may include sub-steps S107-1 to S107-2:

[0102] S107 - 1 , for any particle of a target sub-target plate, a particle of a sub-target plate that is located in the same row as the target sub-target plate and arranged after the target sub-target plate is taken as a first particle.

[0103] The target sub-target plate cannot be the last sub-target plate in a row of sub-target plates. For example, the target sub-target plate cannot be Figure 1 The sub-target plate marked as 3 in the first row, the sub-target plate marked as 6 in the second row, and the sub-target plate marked as 9 in the third row.

[0104] when Figure 1 The sub-target plate marked as 2 is the target sub-target plate. If the sub-target plate marked as 2 is in the same row and is arranged after the sub-target plate marked as 3, then the particle on the sub-target plate marked as 3 is the first particle.

[0105] S107-2, counting the number of point clouds that meet the first preset condition based on the horizontal angles of each point cloud located between the mass point of the target sub-target plate and the first mass point in the average point cloud frame, to obtain the number of horizontal valid point clouds between the mass point of the target sub-target plate and the first mass point;

[0106] Among them, the vertical angle of the point cloud that meets the first preset condition is in the range of [0.5*Vmin,1.5*Vmax] or [0.8*Vmin,1.2*Vmax] or [Vmin-Vstand,Vmax+Vstand], wherein Vmin is the smaller value of the vertical angle of the particle of the target sub-target plate and the vertical angle of the first particle, Vmax is the larger value of the vertical angle of the particle of the target sub-target plate and the vertical angle of the first particle, and Vstand is the nominal vertical angle resolution of the laser radar to be tested.

[0107] The difference between the horizontal angle of the point cloud that meets the first preset condition and the horizontal angle of other point clouds located between the particle on the target sub-target plate and the first particle on the average point cloud frame is less than a first difference, and the first difference is in [0.5*Hstand, 1.5*Hstand], where Hstand is the nominal horizontal angle resolution of the laser radar to be tested.

[0108] If there is no point cloud meeting the first preset condition between the mass point of the target sub-target plate and the first mass point on the average point cloud frame, the number of horizontal valid point clouds between the mass point of the target sub-target plate and the first mass point is 0.

[0109] If a point group that meets the first preset condition exists between the particle located on the target sub-target plate and the first particle on the average point cloud frame, any point cloud in each point group is used as the horizontal valid point cloud of the point group.

[0110] In the embodiment of the present invention, by traversing each sub-target plate, the number of horizontal effective point clouds between the particles of adjacent sub-target plates in each row is obtained.

[0111] For example, Figure 1 The particle of the sub-target plate marked as 1 is recorded as particle 1, the particle of the sub-target plate marked as 2 is recorded as particle 2, ..., the particle of the sub-target plate marked as 9 is recorded as particle 9.

[0112] In the average point cloud frame, by executing the above steps S107-1 to S107-2, the number of horizontal valid point clouds between particle 1 and particle 2, particle 2 and particle 3, particle 4 and particle 5, particle 5 and particle 6, particle 7 and particle 8, and particle 8 and particle 9 is counted and recorded as That is, the number of horizontal valid point clouds between mass points i and j.

[0113] S108, in the average point cloud frame, counting the number of vertical valid point clouds between the particle points of adjacent sub-target plates in each column according to the vertical angle of the particle points of each sub-target plate;

[0114] Among them, the vertical angle of the particle is calculated through the coordinate value of the particle itself.

[0115] In a possible implementation, step S108 may include sub-steps S108-1 to S108-2:

[0116] S108-1: For any particle of a target sub-target plate, a particle of a sub-target plate that is located in the same column as the target sub-target plate and arranged after the target sub-target plate is used as a second particle.

[0117] The target sub-target plate cannot be the last sub-target plate in a row of sub-target plates, for example, the target sub-target plate cannot be Figure 1 The sub-target plate marked as 7 in the first column, the sub-target plate marked as 8 in the second column, and the sub-target plate marked as 9 in the third column.

[0118] when Figure 1 The sub-target plate marked as 2 is the target sub-target plate. If the sub-target plate marked as 2 is in the same column and is arranged after the sub-target plate marked as 5, then the particle on the sub-target plate marked as 5 is the second particle.

[0119] S108-2, based on the vertical angles of each point cloud between the mass point of the target sub-target plate and the second mass point on the average point cloud frame, count the number of point clouds that meet the second preset condition to obtain the number of vertical valid point clouds between the mass point of the target sub-target plate and the second mass point.

[0120] Among them, the horizontal angle of the point cloud that meets the second preset condition is in the range of [0.5*Hmin,1.5*Hmax] or [0.8*Hmin,1.2*Hmax] or [Hmin-Hstand,Hmax+Hstand], wherein Hmin is the smaller value of the vertical angle of the particle of the target sub-target plate and the horizontal angle of the second particle, Hmax is the larger value of the horizontal angle of the particle of the target sub-target plate and the horizontal angle of the second particle, and Hstand is the nominal horizontal angle resolution of the laser radar to be tested.

[0121] The difference between the vertical angle of the point cloud that meets the second preset condition and the vertical angle of other point clouds located between the particle on the target sub-target plate and the second particle on the average point cloud frame is less than the second difference, and the second difference is in [0.5*Vstand,1.5*Vstand], where Vstand is the nominal vertical angle resolution of the laser radar to be tested.

[0122] If there is no point cloud meeting the second preset condition between the mass point located on the target sub-target plate and the second mass point on the average point cloud frame, the number of vertical valid point clouds is 0.

[0123] If there is a point group that meets the second preset condition between the particle located on the target sub-target plate and the first particle on the average point cloud frame, any point cloud in each point group is used as the vertical valid point cloud of the point group.

[0124] In the embodiment of the present invention, each sub-target plate is traversed to obtain the number of vertical effective point clouds between the particles of each column of adjacent sub-target plates.

[0125] For example, Figure 1 The particle of the sub-target plate marked as 1 is recorded as particle 1, the particle of the sub-target plate marked as 2 is recorded as particle 2, ..., the particle of the sub-target plate marked as 9 is recorded as particle 9.

[0126] In the average point cloud frame, by executing the above steps S108-1 to S108-2, the number of vertical valid point clouds between particle 1 and particle 4, particle 4 and particle 7, particle 2 and particle 5, particle 5 and particle 8, particle 3 and particle 6, and particle 6 and particle 9 is counted and recorded as That is, the number of vertical valid point clouds between mass points i and j.

[0127] like Figure 5 As shown, the average point cloud frame can be rasterized, and only one point cloud in one grid is taken as the horizontal valid point cloud. By rasterizing the average point cloud frame, different point cloud formats including regular point clouds and irregular point clouds can be overcome.

[0128] S109: Calculate the horizontal resolution of the laser radar to be tested based on the horizontal angle and the number of horizontal valid point clouds.

[0129] Among them, the horizontal angle, the number of horizontal effective point clouds, and the horizontal resolution of the lidar to be tested satisfy the following formula:

[0130]

[0131] Where, is the horizontal resolution of the laser radar to be tested, is the horizontal angle, is the number of horizontally valid point clouds.

[0132] S110: Calculate the vertical resolution of the laser radar to be tested based on the vertical angle and the vertical effective point cloud.

[0133] Among them, the vertical angle, vertical effective point cloud and vertical resolution of the lidar to be tested satisfy the following formula:

[0134]

[0135] Where, is the vertical resolution of the laser radar to be tested, is the vertical angle, is the number of vertical valid point clouds.

[0136] An embodiment of the present invention also provides a computer-readable storage medium containing a computer program. When the computer program is executed, it can be used to perform the relevant operations in the laser radar resolution testing method provided in the above-mentioned method embodiment.

[0137] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A laser radar resolution test method, characterized in that: The method comprises: Testing is performed using an array target plate, wherein the sub-target plates of the array target plate are arranged in multiple rows in the horizontal direction and in multiple columns in the vertical direction; Determine the center position of each sub-target plate and the coordinate center of the laser radar to be measured; Obtain the horizontal angles between the center positions of two adjacent sub-target plates on the same row of sub-target plates and the lines connecting the coordinate center of the laser radar to be measured; Obtain the vertical angles between the center positions of two adjacent sub-target plates in the same column and the lines connecting the coordinate center of the laser radar to be measured; Starting the laser radar to be tested and emitting laser light toward the array target plate, collecting multiple frames of point cloud, and calculating the average point cloud of the multiple frames of point cloud to obtain an average point cloud frame; Extracting the point cloud of each sub-target plate from the average point cloud frame, and fitting the centroid of each sub-target plate; In the average point cloud frame, the point cloud closest to the center of mass of each sub-target plate is used as the mass point of the sub-target plate; In the average point cloud frame, according to the horizontal angle of the particle points of each sub-target plate, the number of horizontal valid point clouds between the particle points of adjacent sub-target plates in each row is counted; In the average point cloud frame, according to the vertical angle of the particle point of each sub-target plate, the number of vertical valid point clouds between the particle points of adjacent sub-target plates in each column is counted; Calculating the horizontal resolution of the laser radar to be tested according to the horizontal angle and the number of horizontal valid point clouds; The vertical resolution of the laser radar to be tested is calculated based on the vertical angle and the vertical effective point cloud.

2. The method according to claim 1, wherein The step of fitting the centroid of each sub-target plate comprises: The center of mass of each sub-target plate is obtained by averaging the spatial coordinates of each point cloud in the point cloud of each sub-target plate; or the center of mass of each sub-target plate is obtained by averaging the horizontal angles and / or vertical angles of each point cloud in the point cloud of each sub-target plate.

3. The method according to claim 1, wherein The step of taking the point cloud closest to the center of mass of each sub-target plate in the average point cloud frame as the mass point of the sub-target plate comprises: Calculating the spatial distance between each point cloud in the point cloud of the sub-target plate and the sub-target plate's center of mass according to the spatial coordinates of each point cloud in the point cloud of the sub-target plate and the sub-target plate's center of mass, and taking the point cloud in the point cloud of the sub-target plate with the minimum spatial distance to the sub-target plate's center of mass as the sub-target plate's mass point; or According to the horizontal angle and / or vertical angle between each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate, the angular distance between each point cloud in the point cloud of the sub-target plate and the center of mass of the sub-target plate is calculated, and the point cloud in the point cloud of the sub-target plate with the smallest angular distance to the center of mass of the sub-target plate is used as the mass point of the sub-target plate.

4. The method according to claim 1, wherein The step of counting the number of horizontal valid point clouds between the particle points of adjacent sub-target plates in each row in the average point cloud frame according to the horizontal angle of the particle points of each sub-target plate comprises: For any particle point of a target sub-target plate, a particle point of a sub-target plate that is located in the same row as the target sub-target plate and arranged after the target sub-target plate is taken as the first particle point; Counting the number of point clouds that meet a first preset condition based on the horizontal angles of each point cloud located between the mass point of the target sub-target plate and the first mass point on the average point cloud frame, to obtain the number of horizontal valid point clouds between the mass point of the target sub-target plate and the first mass point; Each of the sub-target plates is traversed to obtain the number of horizontal effective point clouds between the mass points of each sub-target plate.

5. The method according to claim 4, wherein The vertical angle of the point cloud that meets the first preset condition is in the range of [0.5*Vmin, 1.5*Vmax] or [0.8*Vmin, 1.2*Vmax] or [Vmin-Vstand, Vmax+Vstand], wherein Vmin is the smaller value of the vertical angle of the mass point of the target sub-target plate and the vertical angle of the first mass point, Vmax is the larger value of the vertical angle of the mass point of the target sub-target plate and the vertical angle of the first mass point, and Vstand is the nominal vertical angle resolution of the laser radar to be tested; The difference between the horizontal angle of the point cloud that meets the first preset condition and the horizontal angle of other point clouds located between the particle of the target sub-target plate and the first particle on the average point cloud frame is less than a first difference, and the first difference is in the range of [0.5*Hstand, 1.5*Hstand], where Hstand is the nominal horizontal angle resolution of the laser radar to be tested; If there is a point group that meets the first preset condition, any point cloud in each of the point groups is used as the horizontal valid point cloud of the point group.

6. The method according to claim 1, wherein The step of counting the number of vertical valid point clouds between the particle points of adjacent sub-target plates in each column in the average point cloud frame according to the vertical angle of the particle points of each sub-target plate comprises: For any particle point of a target sub-target plate, a particle point of a sub-target plate that is located in the same column as the target sub-target plate and arranged after the target sub-target plate is used as a second particle point; Counting the number of point clouds that meet a second preset condition based on the vertical angles of each point cloud between the mass point of the target sub-target plate and the second mass point on the average point cloud frame, to obtain the number of vertical valid point clouds between the mass point of the target sub-target plate and the second mass point; Each of the sub-target plates is traversed to obtain the number of vertical effective point clouds between the particles of each sub-target plate.

7. The method according to claim 6, wherein The horizontal angle of the point cloud that meets the second preset condition is within the range of [0.5*Hmin, 1.5*Hmax] or [0.8*Hmin, 1.2*Hmax] or [Hmin-Hstand, Hmax+Hstand], where Hmin is the smaller value of the vertical angle of the mass point of the target sub-target plate and the horizontal angle of the second mass point, and Hmax is the larger value of the horizontal angle of the mass point of the target sub-target plate and the horizontal angle of the second mass point; Hstand is the nominal horizontal angle resolution of the laser radar to be tested; The difference between the vertical angle of the point cloud that meets the second preset condition and the vertical angle of other point clouds located between the particle of the target sub-target plate and the second particle on the average point cloud frame is less than a second difference value, and the second difference value is in the range of [0.5*Vstand, 1.5*Vstand], where Vstand is the nominal vertical angle resolution of the laser radar to be tested; If there is a point group that meets the second preset condition, any point cloud in each of the point groups is used as a vertical valid point cloud of the point group.

8. The method according to claim 1, wherein The horizontal angle, the number of horizontal valid point clouds, and the horizontal resolution of the laser radar to be tested satisfy the following formula: in, is the horizontal resolution of the laser radar to be tested, is the horizontal angle, is the number of horizontal valid point clouds; The vertical angle, the vertical effective point cloud, and the vertical resolution of the laser radar to be tested satisfy the following formula: in, is the vertical resolution of the laser radar to be tested, is the vertical angle, is the number of vertical valid point clouds.

9. The method according to claim 1, wherein The steps of starting the laser radar to be tested and emitting laser light to the array target plate to collect multiple frames of point clouds include: When the length of the array target plate is less than the nominal horizontal field of view angle of the laser radar to be tested, controlling the electric turntable of the laser radar to be tested to rotate left and right; or When the width of the array target plate is smaller than the vertical field angle of the laser radar to be measured, controlling the turntable of the laser radar to be measured to rotate up and down; By controlling the rotation of the laser radar to be tested, part of the laser energy of the laser radar to be tested that exceeds the array target plate is projected onto the array target plate, thereby obtaining a multi-frame point cloud.

10. A laser radar angular resolution test system, the laser radar angular resolution test system being used to implement the laser radar resolution test method according to any one of claims 1 to 9, characterized in that: Including target plate, total station, laser radar, fixed fixture, two-dimensional electric turntable and control equipment; The laser radar is connected to the two-dimensional electric turntable through the fixing fixture; The emission direction of the laser radar is perpendicular to the target plate; The total station is used to measure the coordinate center position of the laser radar and the center position of each sub-target plate of the array target plate of the target plate; The control device is connected to the laser radar data and is used to control the laser radar or read the data of the laser radar.

11. The system according to claim 10, wherein: The target plate includes a background plate and an array target plate, the array target plate is attached to the background plate, and the reflectivity of the array target plate is greater than that of the background plate; The array target plate is composed of multiple sub-target plates of the same shape. The area of ​​the sub-target plates and the distance between the sub-target plates are determined by the resolution of the laser radar and the imaging distance between the laser radar and the array target plate. The horizontal distance between the sub-target plates is greater than the interval of 10 point clouds in the horizontal direction of the laser radar at the imaging distance, the vertical distance between the sub-target plates is greater than the interval of 10 point clouds in the vertical direction of the laser radar at the imaging distance, and the area of ​​the sub-target plates is greater than the area of ​​3*3 point clouds of the laser radar at the imaging distance.

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