Common-target laser vision high-precision relative pose measurement method and device

Abstract

The invention discloses a common-target laser vision high-precision relative pose measurement method and device, and belongs to the technical field of space measurement. The method is realized by a measuring device in the measuring system, the measuring system further comprises a monocular vision camera and a laser ranging module, the monocular vision camera and the laser ranging module share the same cooperative target array, and the cooperative target array comprises at least three cube-corner prisms to form a three-dimensional structure. Each cube-corner prism has high reflectivity in the illumination wave band of the illumination light source and the working wave band of the laser ranging module; according to the invention, fusion of visual high-precision angle measurement capability and laser high-precision distance measurement capability can be realized by sharing the cooperative target array, and high-precision measurement of six-degree-of-freedom relative poses of a target is realized; besides, the laser ranging module completes orientation capture of the cooperative target array under measurement guide of the monocular vision camera, fusion of laser measurement and vision measurement results is facilitated, measurement errors can be controlled, and measurement precision is improved.

Description

Technical Field

[0001] The present invention relates to the field of space measurement technology, and in particular to a common target laser vision high-precision relative posture measurement method and device. Background Art

[0002] Six-DOF relative pose measurement involves two objects, the measurement system and the target system. According to their configuration characteristics, their respective intrinsic coordinate systems can be established. The purpose of relative pose measurement is to obtain the rotation (relative attitude) and translation (relative position) relationship between the two intrinsic coordinate systems. In the field of space technology, relative pose measurement has a wide range of applications in satellite formation control, baseline measurement, onboard structure monitoring, etc.

[0003] The current six-degree-of-freedom relative pose measurement is a monocular vision measurement technology based on feature point positioning (Perspective-n-Point, PnP). This technology usually arranges a cooperative target array as a feature point in the target system, images it with a monocular camera, and establishes a set of equations containing the relative pose relationship between the camera coordinate system and the target coordinate system based on the pinhole imaging principle, and then solves the relative pose. However, the measurement results of the monocular camera lack target depth information, and the model lacks constraints on the target position in the line of sight direction, resulting in poor measurement accuracy of the target position in this direction. Summary of the invention

[0004] The present invention provides a common target laser vision high-precision relative posture measurement method and device, which can solve the problem of poor measurement accuracy in related technologies. The technical solution is as follows:

[0005] On the one hand, a common target laser vision high-precision relative posture measurement method is provided, which is implemented by a measuring device in a measuring system, wherein the measuring system also includes a monocular vision camera and a laser ranging module, wherein the monocular vision camera is configured with an illumination light source, and the monocular vision camera and the laser ranging module share the same cooperative target array, wherein the cooperative target array includes at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, and each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module; the method includes:

[0006] Acquire a target image obtained by imaging the cooperative target array using a monocular vision camera, extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, and determine the orientation of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; the imaging is completed when the cooperative target array is illuminated by an illumination light source;

[0007] According to the orientation of the ranging target in the visual measurement coordinate system, the orientation of the ranging target in the laser measurement coordinate system is obtained by using the coordinate transformation relationship, and according to the orientation of the ranging target in the laser measurement coordinate system, the light beam transmission direction of the laser ranging module is adjusted so that the light beam points to the ranging target, and then the distance of the ranging target is measured by the laser ranging module; the ranging target is part of the target or all the targets in the cooperative target array;

[0008] Using the coordinate transformation relationship, the distance of the ranging target is converted into the three-dimensional position of the ranging target in the visual measurement coordinate system;

[0009] For the ranging target, the ranging equation is established according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system. For the non-ranging target, the non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model. The equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system.

[0010] On the other hand, a common target laser vision high-precision relative posture measurement device is provided, which is located in a measurement system, wherein the measurement system also includes a monocular vision camera and a laser ranging module, wherein the monocular vision camera is configured with an illumination light source, wherein the monocular vision camera and the laser ranging module share the same cooperative target array, wherein the cooperative target array includes at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, wherein each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module; the measurement device includes:

[0011] An acquisition processing unit is used to acquire a target image obtained by imaging the cooperative target array using a monocular vision camera, and extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, and determine the direction of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; the imaging is completed when the illumination light source illuminates the cooperative target array;

[0012] A processing and adjustment unit is used to obtain the orientation of the ranging target in the laser measurement coordinate system according to the orientation of the ranging target in the visual measurement coordinate system by using a coordinate transformation relationship, and to adjust the light beam transmission direction of the laser ranging module according to the orientation of the ranging target in the laser measurement coordinate system so that the light beam points to the ranging target, and then the laser ranging module measures the distance of the ranging target; the ranging target is part of the target or all the targets in the cooperative target array;

[0013] A position conversion unit, used for converting the distance of the ranging target into the three-dimensional position of the ranging target in the visual measurement coordinate system by using a coordinate transformation relationship;

[0014] The equation construction and solving unit is used to establish the ranging equation for the ranging target according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for the non-ranging target, the non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; the equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system.

[0015] On the other hand, a measurement system is provided, comprising: a measurement device, a monocular vision camera and a laser ranging module, wherein the monocular vision camera is configured with an illumination light source, the monocular vision camera and the laser ranging module share the same cooperative target array, the cooperative target array comprises at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, and each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module;

[0016] The monocular vision camera is used to image the cooperative target array to obtain a target image; the imaging is completed when the illumination light source illuminates the cooperative target array;

[0017] The measuring device is used to extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, determine the orientation of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; obtain the orientation of the ranging target in the laser measurement coordinate system according to the orientation of the ranging target in the visual measurement coordinate system by using the coordinate transformation relationship; adjust the light beam transmission direction of the laser ranging module according to the orientation of the ranging target in the laser measurement coordinate system so that the light beam points to the ranging target, and then the distance of the ranging target is measured by the laser ranging module; use the coordinate transformation relationship to transform the ranging target into the image plane coordinate system; The distance of the target is converted to the three-dimensional position of the ranging target in the visual measurement coordinate system; for the ranging target, a ranging equation is established according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for the non-ranging target, a non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; the equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system; the ranging target is a part of the targets or all the targets in the cooperative target array.

[0018] On the other hand, a computer device is provided, which includes a memory and a processor, the memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to implement the steps of the above-mentioned common-target laser vision high-precision relative pose measurement method.

[0019] On the other hand, a computer-readable storage medium is provided, in which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned common-target laser vision high-precision relative posture measurement method are implemented.

[0020] On the other hand, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the steps of the above-mentioned common-target laser vision high-precision relative pose measurement method.

[0021] The technical solution provided by the present invention can at least bring the following beneficial effects:

[0022] The monocular vision camera and the laser ranging module share the cooperative target array set on the target, which can realize the integration of visual high-precision angle measurement capability and laser high-precision ranging capability, overcome their respective constraints, and realize high-precision measurement of the six-degree-of-freedom relative posture of the target; among them, the laser ranging module completes the orientation capture of the cooperative target array under the measurement guidance of the monocular vision camera, which is conducive to the integration of laser measurement and visual measurement results, thereby controlling measurement errors and improving measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 This is a flow chart of a common target laser vision high-precision relative posture measurement method provided by an embodiment of the present invention;

[0025] Figure 2 is a schematic diagram of a measurement system provided by an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the relative posture measurement of a monocular vision camera provided by an embodiment of the present invention;

[0027] Figure 4 is a schematic diagram of the configuration of a cooperative target array provided by one embodiment of the present invention;

[0028] Figure 5 It is a schematic diagram of the relative pose error obtained by measuring the cooperative target array using only a monocular vision camera;

[0029] Figure 6 This is a schematic diagram of relative posture obtained by the common target laser vision high-precision relative posture measurement method provided by an embodiment of the present invention;

[0030] Figure 7 This is a structural diagram of a common target laser vision high-precision relative posture measurement device provided by one embodiment of the present invention;

[0031] Figure 8 It is a hardware architecture diagram of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] As mentioned above, the problem of poor measurement accuracy of monocular vision can be solved by integrating monocular vision measurement with laser measurement. Laser measurement technology takes advantage of high-precision distance measurement and can provide target position information in the line of sight direction. After integration with the monocular vision measurement results, it can improve the measurement accuracy of the target position in the line of sight direction and achieve high-precision measurement of six-degree-of-freedom relative posture.

[0034] However, in the laser vision fusion measurement technology, the cooperative targets used by the monocular vision camera and the laser ranging module are separated from each other. The monocular vision camera uses an actively luminous LED as a cooperative target, while the laser ranging module uses a corner cube prism as a cooperative target. This structure makes it difficult for the laser ranging module to capture the target position. At the same time, the laser and visual measurement benchmarks and target benchmarks are both in a separated state, which increases the difficulty and complexity of the data fusion between the two, which is not conducive to the improvement of measurement accuracy and the application of the measurement system.

[0035] Therefore, the inventive concept of the present invention is that a monocular vision camera and a laser ranging module share the same cooperative target array, which is composed of at least three corner cube prisms, and the target has high reflectivity in both the illumination band of the monocular vision camera and the working band of the laser ranging module, and can be used for visual imaging and laser ranging at the same time, and high-precision measurement of the six-degree-of-freedom relative posture of the target is achieved through measurement data fusion.

[0036] Please refer to Figure 1A common target laser vision high-precision relative posture measurement method provided by an embodiment of the present invention is implemented by a measuring device in a measuring system, wherein the measuring system further comprises a monocular vision camera and a laser ranging module, wherein the monocular vision camera is provided with an illumination light source, wherein the monocular vision camera and the laser ranging module share the same cooperative target array, wherein the cooperative target array comprises at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, wherein each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module; wherein the method comprises:

[0037] Step 100, obtaining a target image obtained by imaging the cooperative target array using a monocular vision camera, extracting the two-dimensional coordinates of the target in the image plane coordinate system from the target image, and determining the orientation of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; the imaging is completed when the cooperative target array is illuminated by an illumination light source;

[0038] Step 102, according to the orientation of the ranging target in the visual measurement coordinate system, using the coordinate transformation relationship, the orientation of the ranging target in the laser measurement coordinate system is obtained, and according to the orientation of the ranging target in the laser measurement coordinate system, the light beam transmission direction of the laser ranging module is adjusted so that the light beam points to the ranging target, and then the laser ranging module measures the distance of the ranging target; the ranging target is part of the target or all the targets in the cooperative target array;

[0039] Step 104, using a coordinate transformation relationship, converting the distance of the ranging target to a three-dimensional position of the ranging target in a visual measurement coordinate system;

[0040] Step 106, for the ranging target, a ranging equation is established according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for the non-ranging target, a non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; the equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system.

[0041] In the embodiment of the present invention, the monocular vision camera and the laser ranging module share a cooperative target array set on the target, which can realize the fusion of visual high-precision angle measurement capability and laser high-precision ranging capability, overcome their respective constraints, and realize high-precision measurement of the six-degree-of-freedom relative posture of the target; wherein, the laser ranging module completes the orientation capture of the cooperative target array under the measurement guidance of the monocular vision camera, which is conducive to the fusion of laser measurement and visual measurement results, thereby controlling measurement errors and improving measurement accuracy.

[0042] In an embodiment of the present invention, in order to achieve high-precision measurement of the position and posture information of the measurement system and the target system, a cooperative target array is set on the target, and a corner cube prism is used as a target. The number of targets is at least 3, and the setting positions of at least three targets need to form a three-dimensional configuration, which is convenient for characterizing the position and posture of the target. The measurement system adopts a fusion measurement method of laser vision. The monocular vision camera and the laser ranging module share the same cooperative target array, and the monocular vision camera is equipped with an illumination light source. The target has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module, and can be used for imaging of the monocular vision camera and ranging of the laser ranging module at the same time.

[0043] Please refer to Figure 2 , which is a schematic diagram of the measurement system. In this schematic diagram, the cooperative target array consists of 6 targets, namely target 1, target 2, target 3, target 4, target 5 and target 6. Figure 2 Coordinate system O T -X T Y T Z T represents the target coordinate system of the target to be measured, O C -X C Y C Z C represents the intrinsic coordinate system of the monocular vision camera, which is called the visual measurement coordinate system in this embodiment, with the origin O C is the optical center of the camera optical system, L -X L Y L Z L The intrinsic coordinate system of the laser module is referred to as the laser measurement coordinate system in this embodiment. The rotation matrix and translation vector between the coordinate systems are defined as shown in Table 1 below.

[0044] Table 1:

[0045]

[0046] in and Can be obtained through external calibration means, and To be measured.

[0047] Described below Figure 1 How the various steps are performed.

[0048] First, for step 100, a target image is obtained by imaging the cooperative target array using a monocular vision camera, and the two-dimensional coordinates of the target in the image plane coordinate system are extracted from the target image, and the orientation of the target in the visual measurement coordinate system is determined according to the two-dimensional coordinates of the target; the imaging is completed when the cooperative target array is illuminated by an illumination light source.

[0049] In the embodiment of the present invention, the principle of measuring relative posture by a monocular vision camera is as follows: Figure 3 Point P represents any feature point in the target system. After being imaged by a monocular vision camera, an image point P′ is formed on the camera image plane. Two-dimensional coordinate system O I -X I Y I Represents the camera image plane coordinate system. Based on the image taken by the camera, the coordinates of the image point P′ in the image plane coordinate system can be obtained.

[0050] In practical applications, the cooperative target array is used as the feature point of the target, and the coordinates of the i-th target in the target coordinate system are (i=1,2,…,N, N is the number of targets), the coordinates in the visual measurement coordinate system are Here, the symbol H represents the transpose of a matrix or vector. The Euler angles from the target coordinate system to the visual measurement coordinate system are denoted as γ, α, and β. The three angles determine the rotation matrix The value of; translation vector Then it is recorded as [x,y,z] H , γ, α, β, x, y, z are the six unknown quantities to be solved in relative posture measurement, and Y i C and are all functions of these six unknown quantities.

[0051] After the target is imaged onto the camera image plane, the two-dimensional coordinates of the i-th target are The focal length of the camera is F. Based on the pinhole imaging model, the following nonlinear equation system consisting of 2N equations can be established for N targets:

[0052]

[0053] For this set of equations, the initial value can be set and solved by an iterative algorithm. However, in this set of equations, the target position and posture are constrained by the target coordinates, and the target image obtained by the monocular vision camera lacks depth information. Therefore, this set of equations lacks constraints on the target position in the line of sight direction, resulting in poor measurement accuracy of the z-axis target position, which is also the main problem faced by monocular vision relative posture measurement. To solve this problem, it is necessary to introduce constraint information on the target position in the line of sight direction into the measurement system. Therefore, the laser ranging module is used to measure the target distance in the line of sight direction.

[0054] The two-dimensional coordinates of the target in the image plane coordinate system are extracted from the target image. The two-dimensional coordinates of the i-th target are represented as The orientation of the target in the visual measurement coordinate system can be determined based on the two-dimensional coordinates of the target.

[0055] The ranging target is the target that the laser ranging module needs to aim at to measure the distance. The number of ranging targets is m, and the value of m is 1≤m≤N. The targets other than the ranging targets in the cooperative target array are non-ranging targets.

[0056] By determining the direction of the ranging target in the actual measurement coordinate system, the laser ranging module is provided with azimuth guidance so that the laser ranging module can be aligned with the ranging target to achieve high-precision distance measurement.

[0057] Next, for step 102, according to the orientation of the ranging target in the visual measurement coordinate system, the coordinate transformation relationship is used to obtain the orientation of the ranging target in the laser measurement coordinate system. According to the orientation of the ranging target in the laser measurement coordinate system, the light beam transmission direction of the laser ranging module is adjusted so that the light beam points to the ranging target, and then the distance of the ranging target is measured by the laser ranging module.

[0058] according to Figure 2 It can be seen that the laser ranging module includes a laser optical system and a swing mirror. When the laser ranging module measures the cooperative target array, the laser optical fiber system emits a signal laser beam to the cooperative target array to measure the distance of the target; the signal laser beam is reflected by the swing mirror and then emitted toward the target, wherein the swing mirror can swing in two dimensions to control the transmission direction of the laser beam.

[0059] In addition, when the laser ranging module measures the cooperative target array, it is necessary to provide target orientation guidance. In step 100, the orientation of the ranging target in the visual measurement coordinate system is obtained. By using the coordinate transformation relationship between the visual measurement coordinate system and the laser measurement coordinate system, the orientation of the ranging target in the laser measurement coordinate system can be obtained, which is used as the target orientation guidance of the laser ranging module, so that the swing mirror swings to adjust the light beam transmission direction so that the light beam points to the ranging target.

[0060] It can be understood that when there are multiple ranging targets, it is necessary to point to the corresponding ranging targets in turn to measure the distances of the multiple ranging targets in one-to-one correspondence.

[0061] Finally, step 104 "using the coordinate transformation relationship to convert the distance of the ranging target to the three-dimensional position of the ranging target in the visual measurement coordinate system" and step 106 "for the ranging target, establish the ranging equation according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for the non-ranging target, establish the non-ranging equation according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; solve the equation group formed by all targets to obtain the position and posture information of the cooperative target array relative to the measurement system" are explained at the same time.

[0062] In the embodiment of the present invention, the distance of the ranging target is measured by the laser ranging module. Finally, the measurement results of the laser ranging module and the monocular vision camera need to be fused. Therefore, the coordinate transformation relationship between the visual measurement coordinate system and the laser measurement coordinate system can be used to convert the distance of the ranging target to the three-dimensional position of the ranging target in the visual measurement coordinate system.

[0063] Assuming that the number of ranging targets is m and the serial number of the ranging targets is N-m+1-N, then according to the three-dimensional position of the ranging targets, the equations corresponding to these ranging targets in the above equations can be directly replaced to obtain a nonlinear equation group consisting of 2N+m equations; that is:

[0064] The non-range measurement equation established for the non-range measurement target (the serial number of the non-range measurement target is 1-Nm) is:

[0065]

[0066] The distance measurement equation established for the distance measurement target is:

[0067]

[0068] f k (γ,α,β,x,y,z)=Y i C -Y i CR =0,k=3i-N+m-1,i=N-m+1,…,N

[0069]

[0070] Among them, γ, α, β are the Euler angles from the target coordinate system to the visual measurement coordinate system; [x, y, z] H is the translation vector from the visual measurement coordinate system to the target coordinate system; is the two-dimensional coordinate of the target in the image plane coordinate system; is the coordinate of the i-th target in the visual measurement coordinate system; is to convert the distance of the i-th target to the three-dimensional position in the visual measurement coordinate system; F is the focal length of the monocular vision camera; N is the total number of targets in the cooperative target array, N is an integer not less than 3; m is the number of ranging targets, m is an integer not less than 1 and not greater than N, the 1st to (Nm)th targets are non-ranging targets, and the (N-m+1)th to Nth targets are ranging targets;

[0071] in, is the coordinate of the i-th target in the target coordinate system, It is the rotation matrix from the target coordinate system to the visual measurement coordinate system, which is determined by the Euler angle.

[0072] The nonlinear equation group consisting of the above 2N+m equations is the theoretical model for high-precision relative pose measurement of common target laser vision. In this nonlinear equation group, the target information measured by the laser ranging module can impose effective constraints on the distance to the target position for target measurement, making up for the shortcomings of the traditional monocular vision camera pose measurement method and improving the measurement accuracy of the relative position of the target in the z-axis direction in the iterative calculation results.

[0073] It can be understood that if the value of m is equal to N, then the set of equations is entirely composed of equations established for the ranging target.

[0074] In one embodiment of the present invention, please refer to Figure 4 , is a schematic diagram of the configuration of a cooperative target array. The number of targets in the cooperative target array is six;

[0075] Four of the targets are located on the xy plane of the target coordinate system, and the four targets are located on a circle with the origin of the target coordinate system as the center and a diameter of R1; the angles between the lines connecting the four targets and the origin and the positive direction of the x-axis are 45°, 135°, 225° and 315° respectively;

[0076] The positions of the other two targets extend from the intersection of the circle and the x-axis toward the negative direction of the z-axis, forming a height difference of R2 with the remaining four targets.

[0077] In one implementation, R1 is 0.4m and R2 is 0.16m.

[0078] For the measurement system, the pixel number of the monocular vision camera is 2048×2048, the pixel size is 5.5μm, and the camera focal length is 400mm; the distance repeatability measurement accuracy of the laser ranging module is 40m; the distance between the cooperative target array and the measurement system is set to 40m.

[0079] First, as a control, the cooperative target array is measured only by a monocular vision camera, and the relative pose is solved. The six-degree-of-freedom relative pose measurement results are shown in the attached figure. Figure 5 As shown in the figure, it can be seen that for position measurement, the z-axis position measurement accuracy is 12.08mm, which is much worse than the measurement accuracy of the x-axis and y-axis. This is also a concrete manifestation of the insufficiency of monocular vision relative posture measurement.

[0080] The cooperative target array is measured by the common target laser vision high-precision relative pose measurement method in the embodiment of the present invention, and the six-degree-of-freedom relative pose measurement results are obtained as shown in the attached figure. Figure 6As shown, the z-axis position measurement accuracy is 189.66μm, which is significantly improved compared with the monocular vision relative measurement simulation result (12.08mm). The system has the ability to perform high-precision measurement of the target's six-degree-of-freedom relative position.

[0081] Based on the same inventive concept as the above-mentioned common-target laser vision high-precision relative posture measurement method, an embodiment of the present invention provides a common-target laser vision high-precision relative posture measurement device, which is located in a measurement system, wherein the measurement system also includes a monocular vision camera and a laser ranging module, wherein the monocular vision camera is configured with an illumination light source, wherein the monocular vision camera and the laser ranging module share the same cooperative target array, wherein the cooperative target array includes at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, wherein each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module; please refer to Figure 7 , the measuring device comprises:

[0082] The acquisition processing unit 700 is used to acquire a target image obtained by imaging the cooperative target array using a monocular vision camera, and extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, and determine the orientation of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; the imaging is completed when the cooperative target array is illuminated by the illumination light source;

[0083] The processing and adjusting unit 702 is used to obtain the orientation of the ranging target in the laser measurement coordinate system according to the orientation of the ranging target in the visual measurement coordinate system by using the coordinate transformation relationship, and adjust the light beam transmission direction of the laser ranging module according to the orientation of the ranging target in the laser measurement coordinate system so that the light beam points to the ranging target, and then the laser ranging module measures the distance of the ranging target; the ranging target is part of the target or all the targets in the cooperative target array;

[0084] The position conversion unit 704 is used to convert the distance of the ranging target into the three-dimensional position of the ranging target in the visual measurement coordinate system by using the coordinate transformation relationship;

[0085] The equation building and solving unit 706 is used to establish a ranging equation for a ranging target according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for a non-ranging target, establish a non-ranging equation according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; solve the equation group formed by all targets to obtain the position and posture information of the cooperative target array relative to the measurement system.

[0086] In one embodiment of the present invention, the non-range measurement equation established for the non-range measurement target is:

[0087]

[0088] The equation established for the distance measurement target according to the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system is:

[0089]

[0090] f k (γ,α,β,x,y,z)=Y i C -Y i CR =0,k=3i-N+m-1,i=N-m+1,…,N

[0091]

[0092] Among them, γ, α, β are the Euler angles from the target coordinate system to the visual measurement coordinate system; [x, y, z] H is the translation vector from the visual measurement coordinate system to the target coordinate system; is the two-dimensional coordinate of the target in the image plane coordinate system; is the coordinate of the i-th target in the visual measurement coordinate system; is to convert the distance of the i-th target to the three-dimensional position in the visual measurement coordinate system; F is the focal length of the monocular vision camera; N is the total number of targets in the cooperative target array, N is an integer not less than 3; m is the number of ranging targets, m is an integer not less than 1 and not greater than N, the 1st to (Nm)th targets are non-ranging targets, and the (N-m+1)th to Nth targets are ranging targets;

[0093] in, is the coordinate of the i-th target in the target coordinate system, It is the rotation matrix from the target coordinate system to the visual measurement coordinate system, which is determined by the Euler angle.

[0094] It should be noted that the common-target laser vision high-precision relative posture measurement device provided in the above embodiment is only illustrated by the division of the above-mentioned functional modules. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the common-target laser vision high-precision relative posture measurement device provided in the above embodiment and the common-target laser vision high-precision relative posture measurement method embodiment belong to the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0095] Based on the same inventive concept as the above-mentioned common target laser vision high-precision relative posture measurement method, an embodiment of the present invention provides a measurement system, including: a measurement device, a monocular vision camera and a laser ranging module, the monocular vision camera is configured with an illumination light source, the monocular vision camera and the laser ranging module share the same cooperative target array, the cooperative target array includes at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module;

[0096] The monocular vision camera is used to image the cooperative target array to obtain a target image; the imaging is completed when the illumination light source illuminates the cooperative target array;

[0097] The measuring device is used to extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, determine the orientation of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; obtain the orientation of the ranging target in the laser measurement coordinate system according to the orientation of the ranging target in the visual measurement coordinate system by using the coordinate transformation relationship; adjust the light beam transmission direction of the laser ranging module according to the orientation of the ranging target in the laser measurement coordinate system so that the light beam points to the ranging target, and then the distance of the ranging target is measured by the laser ranging module; use the coordinate transformation relationship to transform the ranging target into the image plane coordinate system; The distance of the target is converted to the three-dimensional position of the ranging target in the visual measurement coordinate system; for the ranging target, a ranging equation is established according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for the non-ranging target, a non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; the equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system; the ranging target is a part of the targets or all the targets in the cooperative target array.

[0098] The embodiment of the present application also provides a computer device, please refer to Figure 8 The computer device includes a processor and a memory, in which at least one instruction, at least one program, a code set or an instruction set is stored, and the at least one instruction, at least one program, a code set or an instruction set is loaded and executed by the processor to implement the common-target laser vision high-precision relative posture measurement method provided by the above-mentioned method embodiments.

[0099] An embodiment of the present application also provides a computer-readable storage medium, on which is stored at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by a processor to implement the common-target laser vision high-precision relative pose measurement method provided by the above-mentioned method embodiments.

[0100] An embodiment of the present application also provides a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium, and the processor executes the computer program, so that the computer device executes the common-target laser vision high-precision relative pose measurement method described in any of the above embodiments.

[0101] For the convenience of description, the above system or device is described by dividing it into various modules or units according to its functions. Of course, when implementing the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0102] It can be known from the description of the above implementation methods that those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly contributed to the prior art in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present application or certain parts of the embodiments.

[0103] Finally, it should be noted that, in this article, relational terms such as first, second, third and fourth are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0104] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A common target laser vision high-precision relative posture measurement method, characterized in that: The method is implemented by a measuring device in a measuring system, wherein the measuring system further comprises a monocular vision camera and a laser ranging module, wherein the monocular vision camera is provided with an illumination light source, wherein the monocular vision camera and the laser ranging module share the same cooperative target array, wherein the cooperative target array comprises at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, wherein each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module; and wherein the method comprises: Acquire a target image obtained by imaging the cooperative target array using a monocular vision camera, extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, and determine the orientation of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; the imaging is completed when the cooperative target array is illuminated by an illumination light source; According to the orientation of the ranging target in the visual measurement coordinate system, the orientation of the ranging target in the laser measurement coordinate system is obtained by using the coordinate transformation relationship, and according to the orientation of the ranging target in the laser measurement coordinate system, the light beam transmission direction of the laser ranging module is adjusted so that the light beam points to the ranging target, and then the distance of the ranging target is measured by the laser ranging module; the ranging target is part of the target or all the targets in the cooperative target array; Using the coordinate transformation relationship, the distance of the ranging target is converted into the three-dimensional position of the ranging target in the visual measurement coordinate system; For the ranging target, the ranging equation is established according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system. For the non-ranging target, the non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model. The equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system.

2. The method according to claim 1, characterized in that The non-range-measuring equation established for the non-range-measuring target is: The distance measurement equation established for the distance measurement target is: f k (γ,α,β,x,y,z)=Y i C -Y i CR =0,k=3i-N+m-1,i=N-m+1,…,N Among them, γ, α, β are the Euler angles from the target coordinate system to the visual measurement coordinate system; [x, y, z] H is the translation vector from the visual measurement coordinate system to the target coordinate system; is the two-dimensional coordinate of the target in the image plane coordinate system; is the coordinate of the i-th target in the visual measurement coordinate system; is to convert the distance of the i-th target to the three-dimensional position in the visual measurement coordinate system; F is the focal length of the monocular vision camera; N is the total number of targets in the cooperative target array, N is an integer not less than 3; m is the number of ranging targets, m is an integer not less than 1 and not greater than N, the 1st to (Nm)th targets are non-ranging targets, and the (N-m+1)th to Nth targets are ranging targets; in, is the coordinate of the i-th target in the target coordinate system, It is the rotation matrix from the target coordinate system to the visual measurement coordinate system, which is determined by the Euler angle.

3. The method according to claim 2, characterized in that If the value of m is equal to N, then the set of equations is entirely composed of equations established for the ranging target.

4. The method according to claim 1, characterized in that The number of targets in the cooperative target array is six; Four of the targets are located on the xy plane of the target coordinate system, and the four targets are located on a circle with the origin of the target coordinate system as the center and a diameter of R1; the angles between the lines connecting the four targets and the origin and the positive direction of the x-axis are 45°, 135°, 225° and 315° respectively; The positions of the other two targets extend from the intersection of the circle and the x-axis toward the negative direction of the z-axis, forming a height difference of R2 with the remaining four targets.

5. A common target laser vision high-precision relative posture measurement device, characterized in that: Located in a measurement system, the measurement system also includes a monocular vision camera and a laser ranging module, the monocular vision camera is configured with an illumination light source, the monocular vision camera and the laser ranging module share the same cooperative target array, the cooperative target array includes at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module; the measurement device includes: An acquisition processing unit is used to acquire a target image obtained by imaging the cooperative target array using a monocular vision camera, and extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, and determine the direction of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; the imaging is completed when the illumination light source illuminates the cooperative target array; A processing and adjustment unit is used to obtain the orientation of the ranging target in the laser measurement coordinate system according to the orientation of the ranging target in the visual measurement coordinate system by using a coordinate transformation relationship, and to adjust the light beam transmission direction of the laser ranging module according to the orientation of the ranging target in the laser measurement coordinate system so that the light beam points to the ranging target, and then the laser ranging module measures the distance of the ranging target; the ranging target is part of the target or all the targets in the cooperative target array; A position conversion unit, used for converting the distance of the ranging target into the three-dimensional position of the ranging target in the visual measurement coordinate system by using a coordinate transformation relationship; The equation construction and solving unit is used to establish the ranging equation for the ranging target according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for the non-ranging target, the non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; the equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system.

6. The device according to claim 5, characterized in that The non-range-measuring equation established for the non-range-measuring target is: The distance measurement equation established for the distance measurement target according to the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system is: f k (γ,α,β,x,y,z)=Y i C -Y i CR =0,k=3i-N+m-1,i=N-m+1,…,N Among them, γ, α, β are the Euler angles from the target coordinate system to the visual measurement coordinate system; [x, y, z] H is the translation vector from the visual measurement coordinate system to the target coordinate system; is the two-dimensional coordinate of the target in the image plane coordinate system; is the coordinate of the i-th target in the visual measurement coordinate system; is to convert the distance of the i-th target to the three-dimensional position in the visual measurement coordinate system; F is the focal length of the monocular vision camera; N is the total number of targets in the cooperative target array, N is an integer not less than 3; m is the number of ranging targets, m is an integer not less than 1 and not greater than N, the 1st to (Nm)th targets are non-ranging targets, and the (N-m+1)th to Nth targets are ranging targets; in, is the coordinate of the i-th target in the target coordinate system, It is the rotation matrix from the target coordinate system to the visual measurement coordinate system, which is determined by the Euler angle.

7. A measurement system, characterized in that: include: A measuring device, a monocular vision camera and a laser ranging module, wherein the monocular vision camera is configured with an illumination light source, the monocular vision camera and the laser ranging module share the same cooperative target array, the cooperative target array includes at least three corner cube prisms, and the at least three corner cube prisms form a three-dimensional configuration, and each corner cube prism has a high reflectivity in the illumination band of the illumination light source and the working band of the laser ranging module; The monocular vision camera is used to image the cooperative target array to obtain a target image; the imaging is completed when the illumination light source illuminates the cooperative target array; The measuring device is used to extract the two-dimensional coordinates of the target in the image plane coordinate system from the target image, and determine the orientation of the target in the visual measurement coordinate system according to the two-dimensional coordinates of the target; According to the orientation of the ranging target in the visual measurement coordinate system, the orientation of the ranging target in the laser measurement coordinate system is obtained by using the coordinate transformation relationship. According to the orientation of the ranging target in the laser measurement coordinate system, the light beam transmission direction of the laser ranging module is adjusted so that the light beam points to the ranging target, and then the distance of the ranging target is measured by the laser ranging module; the distance of the ranging target is converted to the three-dimensional position of the ranging target in the visual measurement coordinate system by using the coordinate transformation relationship; for the ranging target, a ranging equation is established according to the three-dimensional position of the ranging target and the coordinate transformation relationship between the visual measurement coordinate system and the target coordinate system; for the non-ranging target, a non-ranging equation is established according to the two-dimensional coordinates of the non-ranging target in the image plane coordinate system and the pinhole imaging model; the equation group formed by all targets is solved to obtain the position and posture information of the cooperative target array relative to the measurement system; the ranging target is a part of the targets or all the targets in the cooperative target array.

8. A computer device, characterized in that: The computer device includes a memory and a processor, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory to implement the steps of any one of the methods described in claims 1-4.

9. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in any one of claims 1 to 4 are implemented.

10. A computer program product, characterized in that The method comprises a computer program, wherein when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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