WO2021051439A1 - Calibration method, apparatus, storage medium and multi-channel lidar - Google Patents

Abstract

A multi-channel LIDAR calibration method, an apparatus, a storage medium and a station, in the LIDAR field. According to an echo intensity of an overlap region of two adjacent fields of view in each of the fields of view, quantitatively measuring an error between two adjacent fields of view, then, determining a calibration coefficient of a field of view to be calibrated according to a reference field of view among multiple fields of view and an error between two adjacent fields of view, and performing calibration of the field of view to be calibrated on the basis of the calibration coefficient, realizing consistency of multiple channels. In this way, LIDAR may accurately reflect a contour of an object when using multiple channels to detect an object.

Description

Calibration method, device, storage medium and multi-channel lidar Technical field

This application relates to the field of lidar, and in particular to a method, device, storage medium and multi-channel lidar for calibrating multi-channel lidar.

Background technique

Lidar can create 3D images of the surroundings. Lidar uses micro-electro-mechanical system (MEMS) micro galvanometer as a beam scanning structure. It is a way of lidar. In order to achieve a larger detection area, it is generally used The method of splicing multiple fields of view expands the area. Multiple fields of view correspond to multiple channels, and each field of view corresponds to a channel. Each channel is composed of a set of laser transmitters, laser receivers, hardware circuits, and optical components. It is an independent unit, and there are differences between each channel. This difference will cause the lidar to scan the same object, and the information in the detected echo laser will be inconsistent, which will make it difficult to identify the contour of the object.

Summary of the invention

The multi-channel lidar calibration method, device, storage medium, and multi-channel lidar provided in the embodiments of the present application can solve the problem of inaccurate object recognition caused by differences in different channels. The technical solution is as follows:

In the first aspect, an embodiment of the present application provides a method for calibrating a multi-channel lidar, and the method includes:

Determine the echo intensity of each illumination point in N fields of view, where N fields of view include 1 reference field of view and N-1 fields of view to be corrected, and N fields of view are field of view 1, field of view 2, ..., the field of view N, any two adjacent fields of view in the N fields of view form N-1 overlapping areas, and the N-1 overlapping areas are respectively S ₁₂ , S ₂₃ , S ₃₄ , ..., S _{( N-1)N} , S _(N-1)N represents the overlapping area between the field of view N-1 and the field of view N, and N is an integer greater than or equal to 2;

Calculate the difference coefficients K ₁₂ , K ₂₃ , ..., K _(N-1)N , where K _(N-1)N is based on _{the echo intensity of S (N-1)N} in the field of view N and S _{(N -1) N is} obtained by the error between the echo intensities in the field of view N-1;

_{Calculate the correction coefficient P j of the} field of view j to be corrected; where i≠j, j=1, 2,..., N, 1≤i≤N, and i is the number of the reference field of view; when j>i, K _i(i-1) , K _(i-1)(i-2) ,..., K _{(j-1)j are} related; when j<i, P _{j is} related to K _j(j-1) , K _(j-1)(j-2) ,..., K _{(i-1)i are} related;

The field of view j to be corrected is corrected according to the correction coefficient P _j.

In a second aspect, an embodiment of the present application provides a multi-channel lidar calibration device, the calibration device includes:

The determining unit is used to determine the echo intensity of each illumination point in the N fields of view, where the N fields of view include 1 reference field of view and N-1 fields of view to be corrected, and the N fields of view are respectively the field of view 1 , Field of view 2,..., field of view N, any two adjacent fields of view in the N fields of view form N-1 overlapping areas, and the N-1 overlapping areas are respectively S ₁₂ , S ₂₃ , S ₃₄ ,..., S _(N-1)N , S _(N-1)N represents the overlapping area between the field of view N-1 and the field of view N, and N is an integer greater than or equal to 2;

The calculation unit is used to calculate the difference coefficients K ₁₂ , K ₂₃ , ..., K _(N-1)N , where K _(N-1)N is the echo in the field of view N according to S _(N-1)N The error between the intensity and the echo intensity of S _{(N-1)N in the field of view N-1;}

The calculation unit is also used to calculate the correction coefficient P _{j of the} field of view j to be corrected; where i≠j, j=1, 2,..., N, 1≤i≤N, and i is the number of the reference field of view; When j>i, K _i(i-1) , K _(i-1)(i-2) ,..., K _{(j-1)j are} related; when j<i, P _{j is} related to K _{j (j-1)} , K _(j-1)(j-2) ,..., K _{(i-1)i are} related;

A correction unit for correcting the field of view j to be corrected _{according to the correction coefficient P j}

In a third aspect, an embodiment of the present application provides a computer storage medium, the computer storage medium stores a plurality of instructions, and the instructions are suitable for being loaded by a processor and executing the above method steps.

In a fourth aspect, an embodiment of the present application provides a multi-channel lidar calibration device, which may include a processor and a memory; wherein the memory stores a computer program, and the computer program is suitable for being loaded and loaded by the processor. Perform the above method steps.

In a fifth aspect, an embodiment of the present application provides a multi-channel lidar, including the above-mentioned multi-channel lidar calibration device.

The beneficial effects brought by the technical solutions provided by some embodiments of the present application include at least:

Determine the relative positional relationship between the various fields of view in the multiple fields of view, and quantitatively measure the echo intensities of the two adjacent fields of view according to the overlap area between the two adjacent fields of view. The difference in the echo intensity between the fields, and then determine the correction coefficient of the field of view to be corrected based on the difference between the reference field of view in the multiple fields of view and the difference between the two adjacent fields of view, and the correction coefficient of the field of view to be corrected based on the correction coefficient The echo intensity is corrected to correct the reflectivity of the detected object. This solves the hardware difference between the multiple channels of the lidar in the related technology, which leads to the different reflectivity detected on the same object, which makes it impossible to accurately identify For the problem of objects, the embodiment of the present application achieves the consistency of multiple channels by correcting multiple channels, so that when the lidar uses multiple channels to detect objects, the contour can be accurately reflected, the difficulty of object recognition is reduced, and the detection accuracy is improved.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

FIG. 1 is a schematic diagram of scanning of a multi-channel lidar provided by an embodiment of the present application;

2 is a schematic flowchart of a method for calibrating a multi-channel lidar provided by an embodiment of the present application;

3 is a schematic diagram of the field of view distribution of a multi-channel lidar provided by an embodiment of the present application;

4 is a schematic diagram of the field of view distribution of a multi-channel lidar provided by an embodiment of the present application;

FIG. 5 is a schematic structural diagram of a multi-channel lidar calibration device provided by the present application;

Fig. 6 is a schematic diagram of another structure of a multi-channel lidar calibration device provided by the present application.

detailed description

In order to make the purpose, technical solutions, and advantages of the present application clearer, the following will further describe the embodiments of the present application in detail with reference to the accompanying drawings.

Figure 1 shows a schematic diagram of the scanning principle that can be applied to the multi-channel lidar provided by the embodiments of this application. The lidar uses 6 fields of view to form the overall field of view of the lidar to detect objects. The 6 fields of view are respectively For field of view 1, field of view 2, field of view 3, field of view 4, field of view 5, and field of view 6, the lidar is equipped with a MEMS micro galvanometer as a scanning device, and one channel is scanned by the MEMS micro galvanometer to form a corresponding Field of view, Lidar controls the deflection angle of the MEMS micro galvanometer to control the scanning angle of each field of view. The 6 channels are scanned by the MEMS micro galvanometer to form 6 fields of view. Each channel includes a laser transmitter and a laser receiver. The manufacturing differences of laser transmitters and laser receivers lead to differences in transmitting power and receiving efficiency. The manufacturing differences in optical circuit components lead to differences in optical efficiency. The superposition of multiple device differences in the channel leads to differences in the channel. Inconsistency between. Lidar detection determines the reflectivity of an object by the intensity of the echo. Lidar scans the same object. The echo intensity of different channels varies greatly due to the inconsistency of the channels, resulting in the same object (same reflectivity) measured in different fields of view The reflectivity is different, which makes it difficult to identify the contour of the object.

In the following, the correction method of the multi-channel lidar provided by the embodiment of the present application will be described in detail with reference to FIG. 2 to FIG. 4. FIG.

Please refer to FIG. 2, which provides a schematic flowchart of a method for calibrating a multi-channel lidar according to an embodiment of this application. As shown in Figure 2, the method of the embodiment of the present application may include the following steps:

S201. Determine the echo intensity of each illumination point in the N fields of view.

Generally, each of the N fields of view corresponds to a channel of the lidar, and N≥2 and an integer, that is, the lidar is provided with N channels. The field of view is the area covered by the laser radar that emits multiple outgoing lasers and receives the echo laser. The outgoing laser encounters an object in the field of view and is reflected by the object and then returns to the echo laser, that is, an outgoing laser is directed to the field of view If there is an object at a specific location in the illuminating point, it will return to the echo laser after being reflected by the object. The intensity of the echo can determine the reflectivity of the object. For the illumination point at the same position in the field of view, the echo intensity of the echo laser received by different channels is the same in an ideal state. Each field of view corresponds to a scanning angle in the horizontal direction, and the scanning angles of the N fields of view may be the same or different, which is not limited in the embodiment of the present application.

Among them, N fields of view are composed of 1 reference field of view and N-1 fields of view to be corrected. The reference field of view can be any of the N fields of view. The reference field of view can be preset, which can be The random selection before performing the calibration is not limited in the embodiment of the present application. For example, the reference field of view may be the first field of view among the N fields of view, or the last field of view among the N fields of view, or a field of view located at an intermediate position among the N fields of view. The N-1 field of view to be corrected and the reference field of view are used as a reference to calibrate the illumination point, so that the same object in any of the N fields of view will have the same echo intensity when detecting the same object.

In a possible implementation, the reference field of view satisfies the following conditions:

When N is an odd number, the number of the reference field of view is i=(N+1)2; when N is an even number, the number of the reference field of view is i=N/2 or N/2+1.

For example: when N=6, the 6 fields of view from left to right are: field of view 1, field of view 2, field of view 3, field of view 4, field of view 5 and field of view 6, then the reference field of view is the field of view Field 3 or Field of View 4.

For another example: when N=7, the 7 fields of view from left to right are: field of view 1, field of view 2, field of view 3, field of view 4, field of view 5, field of view 6, and field of view 7, then The reference field of view is field of view 4.

Among them, N fields of view are respectively field of view 1, field of view 2, ..., field of view N, any two adjacent fields of view of N fields of view form N-1 overlapping areas, namely field of view 1 and field of view 2 is adjacent, the field of view 1 and the field of view 2 have an overlapping area; the field of view 2 and the field of view 3 are adjacent, the field of view 2 and the field of view 3 have an overlapping area; the field of view 3 and the field of view 4 are adjacent, and the field of view 3 and The field of view 4 has an overlapping area, ..., the field of view N-1 and the field of view N are adjacent, and the field of view N-1 and the field of view N have an overlapping area. The N-1 overlapping areas are represented as S ₁₂ , S ₂₃ , S ₃₄ , ..., S _(N-1)N , and S _(N-1)N represents the overlapping area between the field of view N-1 and the field of view N. It should be understood that the number of the field of view and the number of the overlapping area in the embodiment of the present application are only used to distinguish different fields of view and overlapping areas, and are not limited to the embodiments of the present application. The embodiments of the present application may also use other methods to determine the field of view and the overlapping area. For numbering, for example: the field of view is numbered in the manner of field of view 0, field of view 1,..., field of view N-1, and correspondingly, the overlapping area uses S ₀₁ , S ₁₂ , S ₂₃ , S ₃₄ , ..., S _{( N-2)(N-1)} .

For example, as shown in Figure 3, N=6, the lidar uses 6 channels to scan to obtain a scanned image including 6 fields of view. The 6 fields of view are respectively the field of view 1, the field of view 2, the field of view 3, Field of view 4, field of view 5 and field of view 6, there is an overlap area S _{12 between field of view 1 and field of view 2, and there is an overlap area S 23} between field of view 2 and field of view 3, between field of view 3 and field of view 4 There is an overlap area S ₃₄ between the field of view 4 and the field of view 5 there is an overlap area S _{45 , and there is an overlap area S 56} between the field of view 5 and the field of view 6.

In one or more possible embodiments, the method of determining the overlapping area between two adjacent fields of view includes:

The horizontal coincidence and vertical offset of the two fields of view are determined according to the scanning angles of the two adjacent fields of view; the overlap area between the two fields of view is determined according to the horizontal coincidence and the vertical offset.

Among them, the lidar performs scanning in the horizontal and vertical directions, the lidar performs fast-axis scanning in the horizontal direction, and slow-axis scanning in the vertical direction. The scanning angle determines the scanning range of the field of view in the horizontal and vertical directions. The lidar can determine the horizontal coincidence and vertical offset between the two fields of view according to the scanning angle between the two fields of view, and the vertical offset Indicates the vertical misalignment of the two adjacent fields of view of the lidar. The misalignment can be negative or positive.

For example, as shown in Figure 4, the lidar is provided with 6 fields of view: field of view 1 to field of view 6, and the illumination point of each field of view runs from left to right in the horizontal direction, and then back to left from right to left. Scanning, after each line scan is completed, scan the next line up a certain distance. Each field of view has 38 line scans, that is, the illumination points at the boundary of each field of view are numbered from bottom to top: No. 1 to No. 38. Taking field of view 1 and field of view 2 as an example, the horizontal overlap between field of view 1 and field of view 2 is 4 columns, that is, the two rightmost columns of field of view 1 and the leftmost two columns of field of view 2 coincide; The vertical offset between the field of view 1 and the field of view 2 is 2 lines. The irradiation points No. 3 to No. 38 of the field of view 1 coincide with the irradiation points No. 1 to No. 36 of the field of view 2. The lidar can be based on the above horizontal coincidence. And the vertical offset determine the overlap area.

It should be understood that in actual engineering, when multiple channels and MEMS micro galvanometer are assembled, the angle between each channel and MEMS micro galvanometer can be adjusted to ensure that the edges of the two adjacent fields of view are Coincident; further, at least one row of the edges of two adjacent fields of view are coincident.

S202. Calculate difference coefficients K ₁₂ , K ₂₃ , ..., K _(N-1)N .

Among them, the difference coefficient represents the measurement difference produced when two adjacent fields of view (ie, two channels) detect objects with the same reflectivity, and the difference coefficient can be represented by a ratio value, a difference value or other types of values. K _(N-1)N represents the difference coefficient between the N-1th field of view and the Nth field of view, and the difference coefficient K _(N-1)N represents the overlapping area S _(N-1)N in the field of view N -1 is the echo intensity and the difference between the echo intensity of the overlapping area in the field of view N is obtained.

For example: referring to Figure 3, taking the calculation of the difference coefficient between the field of view 2 and the field of view 3 as an example _{, the echo intensity of the overlapping area S 23} in the field of view 2 is obtained as P1, and the overlap is obtained The echo intensity of the area S23 in the field of view 3 is P2, and the coefficient of difference between the field of view 2 and the field of view 3 is K ₂₃ =P1/P2, or K ₂₃ =P1-P2, or K ₂₃ =P2/P1, or K ₂₃ = P2-P1.

In a possible implementation manner, the method for calculating the difference coefficient includes: the first field of view and the second field of view are two adjacent fields of view, and there is an overlapping area between the first field of view and the second field of view, Determine the designated irradiation point in the overlapping area, the number of designated irradiation points is one or more, obtain the first echo intensity of the designated irradiation point in the first field of view, and obtain the first echo intensity of the designated irradiation point in the second field of view. The second echo intensity, the coefficient of difference between the first field of view and the second field of view is determined according to the ratio of the first echo intensity to the second echo intensity.

For example, referring to Figure 3, the designated irradiation point is the irradiation point A in the overlapping area between the field of view 2 and the field of view 3, and the echo intensity of the irradiation point A in the field of view 2 is obtained as P1. The echo intensity of the irradiation point A in the field of view 3 is P2, and the ratio of the echo intensity P1 to the echo intensity P2 is taken as the coefficient of difference between the field of view 2 and the field of view 3.

In another possible implementation manner, the method for calculating the difference coefficient includes: the first field of view and the second field of view are two adjacent fields of view, and there is an overlap area between the first field of view and the second field of view , Determine all the illumination points included in the overlapping area, obtain the average echo intensity of all illumination points in the first field of view, and obtain the average echo intensity of all illumination points in the second field of view, according to the two average echo intensities The ratio of determines the coefficient of difference between the first field of view and the second field of view.

Among them, when the ratio value is used to represent the difference coefficient between the two fields of view, the difference coefficient is determined by the relative position between the overlap area and the reference area, and the overlap area of the first field of view and the second field of view is located in the reference field of view. The echo intensity of the overlap area in the first field of view is P1, the echo intensity of the overlap area in the second field of view is P2, and the coefficient of difference between the first field of view and the second field of view is equal to P2 /P1. When the overlapping area of the first field of view and the second field of view is located to the right of the reference field of view, the echo intensity of the overlapping area in the first field of view is P1, and the echo intensity of the overlapping area in the second field of view is P2, The coefficient of difference between the first field of view and the second field of view is equal to P1/P2.

For example, referring to Figure 3, the reference field of view is field of view 3, the overlapping area between field of view 1 and field of view 2 is denoted as S ₁₂ (not shown in the figure), and the field of view 2 and field of view 3 are The overlap area _{between field of view 3 and field of view 4 is denoted as S 23} , the overlap area between field of view 3 and field of view 4 is denoted as S ₃₄ , the overlap area between field of view 4 and field of view 5 is denoted as S ₄₅ , field of view 5 and field of view 6 The overlapping area between is denoted as S ₅₆ . The overlapping area S ₁₂ and the overlapping area S _{23 are} located on the left side of the reference field of view, and the overlapping areas S ₃₄ , S ₄₅ and S _{56 are} located on the right side of the reference field of view.

The echo intensity of the overlapping area S ₁₂ in the field of view 1 is obtained as

The echo intensity of the overlapping area in the field of view 2 is

Difference coefficient between field of view 1 and field of view 2

Obtain the echo intensity of the overlapping area S ₂₃ in the field of view 2

The echo intensity of the overlapping area S ₂₃ in the field of view 3

Then the coefficient of difference between field of view 2 and field of view 3

Obtain the echo intensity of the overlapping area S34 in the field of view 3

The echo intensity of the overlapping area S34 in the field of view 4

Then the coefficient of difference between field of view 3 and field of view 4

Obtain the echo intensity of the overlapping area S ₄₅ in the field of view 4

Obtain the echo intensity of the overlapping area S ₄₅ in the field of view 5

Then the coefficient of difference between field of view 4 and field of view 5

Obtain the echo intensity of the overlapping area S56 in the field of view 5

Obtain the echo intensity of the overlapping area S56 in the field of view 6

Then the coefficient of difference between field of view 5 and field of view 6

S203: Calculate the correction coefficient P _{j of the} field of view j to be corrected.

Among them, j represents the number of the field of view to be corrected, P _j represents the correction coefficient of the j-th field of view to be corrected, i represents the number of the reference field of view, and the reference field of view is any one of the N fields of view, that is, 1≤i ≤N, and i is an integer, j≠i, j=1, 2,...,N. When j>i, P _{j is} related to K _i(i-1) , K _(i-1)(i-2) ,..., K _(j-1)j ; when j<i, P _{j is} related to K _j(j-1) , K _(j-1)(j-2) ,..., K _{(i-1)i are} related.

For example, N=6, the N fields of view are field of view 1, field of view 2, field of view 3, field of view 4, field of view 5, and field of view 6, field of view 3 is the reference field of view, field of view 1 and The field of view 2 is located on the left of the field of view 3, that is, it satisfies j<i; the field of view 4, the field of view 5, and the field of view 6 are located on the right of the field of view 3, that is, j>i is satisfied. The correction coefficient P ₁ represents the correction coefficient of the field of view 1, the correction coefficient P ₂ represents the correction coefficient of the field of view 2, the correction coefficient P ₄ represents the correction coefficient of the field of view 4, the correction coefficient P ₅ represents the correction coefficient of the field of view 5. P ₆ represents the correction coefficient of the field of view 6. Assuming that the coefficient of difference between field of view 1 and field of view 2 is K ₁₂ , the coefficient of difference between field of view 2 and field of view 3 is K ₂₃ , and the coefficient of difference between field of view 3 and field of view 4 is K ₃₄ , The coefficient of difference between field 4 and field of view 5 is K ₄₅ , and the coefficient of difference between field of view 5 and field of view 6 is K ₅₆ . Then the correction coefficient P _{1 is} related to the difference coefficients K ₁₂ and K ₂₃ , for example: the correction coefficient P ₁ =K ₁₂ ×K ₂₃ . The correction coefficient P _{2 is} related to the difference coefficient K ₂₃ , for example: the correction coefficient P ₂ =K ₂₃ . The correction coefficient P _{4 is} related to the difference coefficient K ₃₄ , for example: the correction coefficient P ₄ =K ₃₄ . The correction coefficient P _{5 is} related to the difference coefficients K ₃₄ and K ₄₅ , for example: correction coefficient = K ₃₄ × K ₄₅ . The correction coefficient P _{6 is} related to the difference coefficients K ₃₄ , K ₄₅ and K ₅₆ , for example: correction coefficient = K ₃₄ × K ₄₅ × K ₅₆ .

S204: Correct the field of view j to be corrected according to the correction coefficient P _j.

Among them, each field of view to be corrected multiplies the correction coefficients to obtain the corrected field of view. For example: the field of view 1 to be corrected is composed of the irradiation points of 38 line scans. According to S203, the correction coefficient of the field of view 1 to be corrected is P ₁ , and the echo intensities of all the irradiation points in the field of view 1 to be corrected are multiplied by the correction coefficient After P ₁ , the echo intensity of all irradiated points in the corrected field of view 1 is obtained.

Implement the embodiment of this application to determine the relative positional relationship between the various fields of view in multiple fields of view, and quantitatively measure the echo intensities of the overlapping areas between two adjacent fields of view in the two fields of view. The error of the echo intensity between two adjacent fields of view is then determined according to the reference field of view in multiple fields of view and the error between the two adjacent fields of view to determine the correction coefficient of the field of view to be corrected, based on the correction The coefficient is used to correct the echo intensity of the field of view to be calibrated to realize the correction of the reflectivity of the detected object, so as to solve the hardware difference between the multiple channels of the lidar in the related technology, which leads to the reflectivity of the same object detected Different, so that the object cannot be accurately identified, the embodiment of the application achieves the consistency of multiple channels by correcting multiple channels, so that when the lidar uses multiple channels to detect objects, the outline can be accurately reflected and the difficulty of object identification is reduced. Improve detection accuracy.

The following are device embodiments of this application, which can be used to execute the method embodiments of this application. For details not disclosed in the device embodiment of this application, please refer to the method embodiment of this application.

Please refer to FIG. 5, which shows a schematic structural diagram of a correction device for a multi-channel radar provided by an exemplary embodiment of the present application, which is referred to as the correction device 5 hereinafter. The correction device 5 can be implemented as all or part of the lidar through software, hardware or a combination of the two. The correction device 5 includes: a determination unit 501, a calculation unit 502, and a correction unit 503.

Optionally, when N is an odd number, i=(N+1)/2; or

When N is an even number, i=N/2 or N/2+1.

Alternatively, the K _{(N-1) N} represents S _{(N-1) N} echo intensities in the field of view of N and the S _(N-1) of the _N field in the N-1 The value of the ratio between the intensities of the echoes.

Optionally, the _{echo intensity of the S (N-1)N} in the field of view N-1 represents the magnitude _{of all the illumination points in the S (N-1)N} in the field of view N-1 The average echo intensity, the echo intensity of the S _(N-1)N in the field of view N represents the average echo of all the illumination points in the _{S (N-1)N in the field of view N} strength.

Optionally, the _{echo intensity of the S (N-1)N} in the field of view N represents the echo intensity of a designated illumination point in the field of view N, and the S _{(N-1)N is} in the field of view N. The echo intensity in the field of view N-1 represents the echo intensity of the designated irradiation point in the field of view N-1, and the designated irradiation point is located in the last column of the field of view N-1; or The designated illumination point is located in the first column of the field of view N.

Optionally, the determining unit 501 is further configured to:

Determining the horizontal coincidence degree and the vertical offset between the two adjacent fields of view according to the scanning angles of the two adjacent fields of view;

The overlapping area between the two fields of view is determined according to the horizontal coincidence degree and the vertical offset.

Optionally, the scanning angles of the N fields of view are the same.

It should be noted that when the device 5 provided in the foregoing embodiment executes the multi-channel lidar calibration method, only the division of the foregoing functional modules is used as an example for illustration. In practical applications, the foregoing functional assignments can be assigned to different types according to needs. The function module is completed, that is, the internal structure of the device is divided into different function modules to complete all or part of the functions described above. In addition, the multi-channel lidar calibration device provided in the above embodiment and the multi-channel lidar calibration method embodiment belong to the same concept, and the implementation process is detailed in the method embodiment, which will not be repeated here.

The serial numbers of the foregoing embodiments of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments.

The embodiment of the present application also provides a computer storage medium. The computer storage medium may store a plurality of instructions, and the instructions are suitable for being loaded by a processor and executing the method steps of the embodiments shown in FIGS. 2 to 4 above. For the specific execution process, please refer to the specific description of the embodiment shown in FIG. 2 to FIG. 4, which will not be repeated here.

The present application also provides a computer program product, which stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement the multi-channel radar calibration method described in each of the above embodiments.

Please refer to FIG. 6, which provides a schematic structural diagram of a correction device for a multi-channel lidar according to an embodiment of the present application. The correction and correction device 6 is described below. As shown in FIG. 6, the correction device 6 may include: at least one processor 601, a memory 602, and at least one communication bus 603.

Among them, the communication bus 603 is used to implement connection and communication between these components.

The processor 601 may include one or more processing cores. The processor 601 uses various interfaces and lines to connect various parts of the entire correction device 6, and executes by running or executing instructions, programs, code sets, or instruction sets stored in the memory 602, and calling data stored in the memory 602. Various functions and processing data of the correction device 6. Optionally, the processor 601 may use at least one of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), and Programmable Logic Array (PLA) Realize in the form of hardware. The processor 601 may integrate one or a combination of a central processing unit (CPU), a graphics processing unit (GPU), a modem, and the like. Among them, the CPU mainly processes the operating system, user interface, and application programs; the GPU is used to render and draw the content that needs to be displayed on the display; the modem is used to process wireless communication. It can be understood that the above-mentioned modem may not be integrated into the processor 601, but may be implemented by a chip alone.

The memory 602 may include random access memory (RAM) or read-only memory (Read-Only Memory). Optionally, the memory 602 includes a non-transitory computer-readable storage medium. The memory 602 may be used to store instructions, programs, codes, code sets or instruction sets. The memory 602 may include a storage program area and a storage data area, where the storage program area may store instructions for implementing the operating system and instructions for at least one function (such as touch function, sound playback function, image playback function, etc.), Instructions used to implement the foregoing method embodiments, etc.; the storage data area can store data and the like involved in the foregoing method embodiments. Optionally, the memory 602 may also be at least one storage device located far away from the foregoing processor 601.

In the correction device 6 shown in FIG. 6, the processor 601 may be used to call the touch operation response application program stored in the memory 602, and specifically execute the following steps:

Determine the echo intensity of each illumination point in the N fields of view; wherein, the N fields of view include 1 reference field of view and N-1 fields of view to be corrected, and the N fields of view are respectively the field of view 1, Field of view 2, ..., field of view N, any two adjacent fields of view in the N fields of view form N-1 overlapping areas, and the N-1 overlapping areas are respectively S ₁₂ , S ₂₃ , S ₃₄ , …, S _(N-1)N , S _(N-1)N represents the overlapping area between the field of view N-1 and the field of view N, where N≥2 and N is an integer;

Calculate the difference coefficients K ₁₂ , K ₂₃ , ..., K _(N-1)N ; where K _(N-1)N is based on the _{return of the S (N-1)N} in the field of view N-1 Obtained from the difference between the wave intensity and the _{echo intensity of the S (N-1)N} in the field of view N;

_{Calculate the correction coefficient P j of the} field of view j to be corrected; where j = 1, 2, ..., N, i≠j, 1≤i≤N, and i is the number of the reference field of view; when j>i, P _{j is} related to K _i(i-1) , K _(i-1)(i-2) ,..., K _(j-1)j ; when j<i, P _j and K _{j(j- 1)} , K _(j-1)(j-2) ,..., K _{(i-1)i are} related;

The field of view j to be corrected is corrected according to the correction coefficient P _j.

In one or more embodiments, when N is an odd number, i=(N+1)/2; or

When N is an even number, i=N/2 or N/2+1.

In one or more embodiments, the K _(N-1)N represents _{the echo intensity of S (N-1)N} in the field of view N and the S _(N-1)N in the field of view N The value of the ratio between the intensities of the echoes in the field of view N-1.

In one or more embodiments _{, the echo intensity of the S (N-1)N} in the field of view N-1 indicates that all the illumination points in the _{S (N-1)N are in the field of view.} The average echo intensity in N-1, the echo intensity of the S _(N-1)N in the field of view N indicates that all the illumination points in the _{S (N-1)N are in the field of view N} The average echo strength in.

In one or more embodiments _{, the echo intensity of the S (N-1)N} in the field of view N represents the echo intensity of a designated illumination point in the field of view N, and the S _{(N -1)} The echo intensity of N in the field of view N-1 represents the echo intensity of the designated irradiation point in the field of view N-1, and the designated irradiation point is located in the field of view N-1 Or the designated illumination point is located in the first column of the field of view N.

In one or more embodiments, the processor 601 is further configured to execute:

Determining the horizontal coincidence degree and the vertical offset between the two adjacent fields of view according to the scanning angles of the two adjacent fields of view;

The overlapping area between the two fields of view is determined according to the horizontal coincidence degree and the vertical offset.

In one or more embodiments, the scanning angles of the N fields of view are the same.

Among them, the embodiment of FIG. 6 and the method embodiment of FIG. 2 are based on the same concept, and the technical effects brought about by them are also the same. For the specific implementation process of FIG. 6, reference may be made to the description of FIG. 2 and will not be repeated here.

A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing relevant hardware through a computer program. The program can be stored in a computer readable storage medium, and the program can be stored in a computer readable storage medium. During execution, it may include the procedures of the above-mentioned method embodiments. Wherein, the storage medium can be a magnetic disk, an optical disc, a read-only storage memory or a random storage memory, etc.

The above-disclosed are only preferred embodiments of this application, and of course the scope of rights of this application cannot be limited by this. Therefore, equivalent changes made in accordance with the claims of this application still fall within the scope of this application.

Claims (11)

1. A method for calibrating multi-channel lidar, characterized in that the method includes:

   Determine the echo intensity of each illumination point in the N fields of view; wherein, the N fields of view include 1 reference field of view and N-1 fields of view to be corrected, and the N fields of view are respectively the field of view 1, Field of view 2, ..., field of view N, any two adjacent fields of view in the N fields of view form N-1 overlapping areas, and the N-1 overlapping areas are respectively S ₁₂ , S ₂₃ , S ₃₄ , …, S _(N-1)N , S _(N-1)N represents the overlapping area between the field of view N-1 and the field of view N, where N≥2 and N is an integer;

   Calculate the difference coefficients K ₁₂ , K ₂₃ , ..., K _(N-1)N ; where K _(N-1)N is based on the _{return of the S (N-1)N} in the field of view N-1 Obtained from the difference between the wave intensity and the _{echo intensity of the S (N-1)N} in the field of view N;

   _{Calculate the correction coefficient P j of the} field of view j to be corrected; where j = 1, 2, ..., N, i≠j, 1≤i≤N, and i is the number of the reference field of view; when j>i, P _{j is} related to K _i(i-1) , K _(i-1)(i-2) ,..., K _(j-1)j ; when j<i, P _j and K _{j(j- 1)} , K _(j-1)(j-2) ,..., K _{(i-1)i are} related;

   The field of view j to be corrected is corrected according to the correction coefficient P _j.
2. The method of claim 1, wherein:

   When N is an odd number, i=(N+1)/2; or

   When N is an even number, i=N/2 or N/2+1.
3. The method according to claim 1 or 2, wherein the K _(N-1)N represents _{the echo intensity of S (N-1)N} in the field of view N and the S _{(N- 1) N} is the ratio of the echo intensities in the field of view N-1.
4. The method according to claim 3, wherein _{the echo intensity of the S (N-1)N} in the field of view N-1 indicates that all the illumination points in _{the S (N-1)N are} The average echo intensity in the field of view N-1, the echo intensity of the S _(N-1)N in the field of view N indicates that all the illumination points in _{the S (N-1)N are in the} The average echo intensity in the field of view N.
5. The method according to claim 3, wherein _{the echo intensity of the S(N-1)N} in the field of view N represents the echo intensity of a designated illumination point in the field of view N, so The echo intensity of S _(N-1)N in the field of view N-1 represents the echo intensity of the designated illumination point in the field of view N-1, and the designated illumination point is located in the field of view N-1. The last column of the field N-1; or the designated illumination point is located in the first column of the field of view N.
6. The method according to claim 4 or 5, further comprising:

   Determining the horizontal coincidence degree and the vertical offset between the two adjacent fields of view according to the scanning angles of the two adjacent fields of view;

   The overlapping area between the two fields of view is determined according to the horizontal coincidence degree and the vertical offset.
7. The method according to claim 6, wherein the scanning angles of the N fields of view are the same.
8. A correction device for multi-channel lidar, characterized in that the device comprises:

   The determining unit is used to determine the echo intensity of each illumination point in the N fields of view; wherein the N fields of view include 1 reference field of view and N-1 fields of view to be corrected, and the N fields of view are respectively Is the field of view 1, the field of view 2, ... the field of view N, any two adjacent fields of view in the N fields of view form N-1 overlapping areas, and the N-1 overlapping areas are respectively S ₁₂ and S ₂₃ , S ₃₄ , ..., S _(N-1)N , S _(N-1)N represents the overlapping area between the field of view N-1 and the field of view N, N≥2 and N is an integer;

   The calculation unit is used to calculate the difference coefficients K ₁₂ , K ₂₃ , ..., K _(N-1)N ; where K _(N-1)N is based on S _(N-1)N in the field of view N Obtained by the error between the echo intensity and the echo intensity of the S _(N-1)N in the field of view N-1;

   The calculation unit is also used to calculate the correction coefficient P _{j of the} field of view j to be corrected; where i≠j, 1≤i≤N, j=1, 2,...,N, and i is the number of the reference field of view; When j>i, the correction coefficient P _{j is} related to K _i(i-1) , K _(i-1)(i-2) ,..., K _(j-1)j ; or when j<i, correct The coefficient P _{j is} related to K _j(j-1) , K _(j-1)(j-2) ,..., K _(i-1)(i) ;

   The correction unit is configured to correct the echo intensity of each irradiation point in the field of view j to be corrected according to the correction coefficient P _j.
9. A computer storage medium, wherein the computer storage medium stores a plurality of instructions, and the instructions are suitable for being loaded by a processor and executing the method steps according to any one of claims 1-7.
10. A calibration device for multi-channel lidar, which is characterized by comprising: a processor and a memory; wherein the memory stores a computer program, and the computer program is adapted to be loaded by the processor and executed as claimed in claim 1 to 7 Any one of the method steps.
11. A multi-channel lidar, which is characterized by comprising the correction device according to claim 8 or 10.

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