Real-time feedback rigid body six-degree-of-freedom measurement method, device and equipment and medium

Abstract

The invention relates to a rigid body measurement technology, and discloses a real-time feedback rigid body six-degree-of-freedom measurement method, device and equipment and a storage medium. The method comprises the following steps: acquiring initial camera internal and external parameters of a monocular camera according to a checkerboard calibration plate; acquiring a rigid body image to obtain a rigid body historical image sequence and a rigid body real-time image; performing feature extraction on the rigid body historical image sequence to obtain a feature set of each rigid body marker; dynamically adjusting the initial camera internal and external parameters according to a pre-constructed minimization re-projection error algorithm and the rigid body marker feature set to obtain dynamic camera internal and external parameters; and carrying out image feature extraction on the rigid body real-time image to obtain a rigid body real-time feature set, and carrying out six-degree-of-freedom measurement on the rigid body real-time feature set according to the dynamic camera internal and external parameters to obtain a rigid body measurement result. According to the invention, the rigid body can be dynamically and accurately measured through monocular vision.

Description

Technical Field

[0001] The present invention relates to the field of rigid body measurement technology, and in particular to a rigid body six-degree-of-freedom measurement method, device, equipment and computer-readable storage medium with real-time feedback. Background Art

[0002] In the field of machine vision and precision measurement, the six-degree-of-freedom measurement technology of rigid bodies has always been a hot topic of research. The traditional measurement method uses a checkerboard to configure the parameters of a monocular vision camera, which is more suitable for static measurement environments. However, when used in a dynamic environment, as the rigid body and the camera move, the internal and external parameters of the camera drift, resulting in inaccurate measurements. Summary of the invention

[0003] The present invention provides a real-time feedback rigid body six-degree-of-freedom measurement method, device, equipment and storage medium, the main purpose of which is to perform dynamic and accurate measurement of the rigid body through monocular vision.

[0004] To achieve the above object, the present invention provides a real-time feedback rigid body six-degree-of-freedom measurement method, comprising:

[0005] Use the pre-built checkerboard calibration plate to initialize the calibration operation of the pre-built monocular camera to obtain the initial camera internal and external parameters;

[0006] Acquire a rigid body with a preset chessboard marker attached thereto, and continuously capture and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image;

[0007] Extracting a rigid body historical image from the rigid body historical image sequence in sequence, and performing image feature extraction on the rigid body historical image to obtain a rigid body marker feature set;

[0008] According to the pre-built minimization reprojection error algorithm and the rigid body marker feature set, the initial camera intrinsic and extrinsic parameters are dynamically adjusted to obtain dynamic camera intrinsic and extrinsic parameters, and the initial camera intrinsic and extrinsic parameters are updated using the dynamic camera intrinsic and extrinsic parameters;

[0009] After the traversal of the rigid body historical images in the rigid body historical image sequence is completed, image features are extracted from the rigid body real-time images to obtain a rigid body real-time feature set, and six-degree-of-freedom measurement is performed on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

[0010] Optionally, the using the monocular camera to continuously capture and photograph the rigid body to obtain a rigid body historical image sequence and a rigid body real-time image includes:

[0011] Acquire the real-time captured image of the monocular camera in real time, and perform object recognition on the real-time captured image to obtain an object recognition result;

[0012] Determining whether a preset checkerboard marker object appears in the object recognition result;

[0013] When the checkerboard marker object appears in the object recognition result, the checkerboard marker object is recorded as a target to obtain a wall historical image video;

[0014] When a photography instruction is received from the user, the rigid body historical image video is intercepted to obtain a rigid body real-time image, and the video in the rigid body historical image video that is in a preset time period before the rigid body real-time image is collected according to a preset interception frequency to obtain a rigid body historical image sequence.

[0015] Optionally, dynamically adjusting the initial camera intrinsic and extrinsic parameters according to the pre-built minimization reprojection error algorithm and the rigid body marker feature set to obtain dynamic camera intrinsic and extrinsic parameters includes:

[0016] Obtaining model size information of the rigid body;

[0017] Using a pre-built camera projection algorithm, according to the initial camera internal and external parameters and model size information, the rigid body is image predicted to obtain a rigid body prediction image;

[0018] According to a pre-built algorithm for minimizing reprojection errors, the difference between the rigid body marker feature set and the rigid body prediction image is calculated to obtain a reprojection error;

[0019] The reprojection error is minimized using a pre-constructed least squares method to obtain dynamic camera internal and external parameters.

[0020] Optionally, the updating the initial camera intrinsic and extrinsic parameters by using the dynamic camera intrinsic and extrinsic parameters includes:

[0021] The difference between the dynamic camera internal and external parameters and the initial camera internal and external parameters is calculated by using a pre-built incremental algorithm to obtain a parameter increment, wherein the incremental algorithm is expressed as:

[0022] P updated =P initial +α(P dynamic -P initial )

[0023] Where P updated represents the updated initial camera internal and external parameters, P initial represents the initial camera internal and external parameters, P dynamicrepresents the internal and external parameters of the dynamic camera, and α represents the smoothing factor ranging from 0 to 1;

[0024] The initial camera intrinsic and extrinsic parameters are weightedly calculated according to the parameter increment to obtain updated initial camera intrinsic and extrinsic parameters.

[0025] Optionally, the pre-built checkerboard calibration plate is used to perform an initial calibration operation on the pre-built monocular camera to obtain initial camera internal and external parameters, including:

[0026] Using a pre-built monocular camera, according to the preset multi-angle position information, a pre-built checkerboard calibration plate is used to obtain a calibration image sequence;

[0027] Performing a checkerboard corner point feature extraction operation on the calibration image sequence to obtain a corner point feature information set;

[0028] Acquire the size layout information of the checkerboard calibration plate, quantize the size layout information, and obtain a checkerboard layout feature vector;

[0029] By using a pre-built calibration algorithm, shooting parameters of the corner point feature information are identified according to the checkerboard layout feature vector to obtain initial camera internal and external parameters.

[0030] Optionally, the extracting image features from the rigid body historical image to obtain a rigid body marker feature set includes:

[0031] Graying the rigid body historical image to obtain a rigid body gray image, and performing Gaussian filtering and smoothing on the rigid body gray image to obtain a rigid body denoised gray image;

[0032] Performing a feature extraction operation on the rigid body denoised grayscale image to obtain a rigid body image feature set;

[0033] The rigid body image feature set is subjected to feature classification judgment based on preset markers to obtain a rigid body marker feature set.

[0034] Optionally, after obtaining the rigid body measurement result, the method further includes:

[0035] Using two cameras in a pre-built experimental platform to obtain real measurement results of the rigid body;

[0036] Performing difference calculation using the rigid body measurement result and the true measurement result to obtain a measurement difference;

[0037] Determining whether the measured difference is greater than a preset qualified threshold;

[0038] When the measured difference is greater than a preset qualified threshold, an alarm prompt message is generated.

[0039] In order to solve the above problems, the present invention also provides a rigid body six-degree-of-freedom measurement device with real-time feedback, the device comprising:

[0040] The camera parameter initialization module is used to use the pre-built checkerboard calibration plate to initialize the calibration operation of the pre-built monocular camera to obtain the initial camera internal and external parameters;

[0041] A rigid body image acquisition module is used to acquire a rigid body with a preset checkerboard marker attached thereto, and continuously acquire and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image;

[0042] A parameter real-time updating module is used to extract a rigid body historical image from the rigid body historical image sequence in turn, and perform image feature extraction on the rigid body historical image to obtain a rigid body marker feature set, and dynamically adjust the initial camera internal and external parameters according to a pre-built minimization reprojection error algorithm and the rigid body marker feature set to obtain dynamic camera internal and external parameters, and use the dynamic camera internal and external parameters to update the initial camera internal and external parameters;

[0043] The rigid body measurement module is used to extract image features of the rigid body real-time image after the traversal of the rigid body historical images in the rigid body historical image sequence is completed to obtain a rigid body real-time feature set, and to perform six-degree-of-freedom measurement on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

[0044] In order to solve the above problem, the present invention further provides an electronic device, the electronic device comprising:

[0045] at least one processor; and,

[0046] a memory communicatively connected to the at least one processor; wherein,

[0047] The memory stores a computer program that can be executed by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the above-mentioned real-time feedback rigid body six-degree-of-freedom measurement method.

[0048] In order to solve the above problems, the present invention also provides a computer-readable storage medium, in which at least one computer program is stored. The at least one computer program is executed by a processor in an electronic device to implement the above-mentioned real-time feedback rigid body six-degree-of-freedom measurement method.

[0049] The embodiment of the present invention first calibrates the parameters of the monocular camera through a checkerboard calibration plate to obtain the initial camera internal and external parameters, and then takes photos through a rigid body marked with a checkerboard marker; the present invention adopts a preview method to use the calibration results in the shooting interval as prior information, continuously calculates the dynamic camera internal and external parameters, and updates the initial camera internal and external parameters, so that the final measurement process is more accurate. In addition, when updating the initial camera internal and external parameters, the present invention adopts an incremental algorithm instead of direct replacement, which greatly improves the stability of the initial camera internal and external parameters during the update process, making it less likely for the parameters to drift and cause measurement result deviations. Therefore, the embodiment of the present invention provides a real-time feedback rigid body six-degree-of-freedom measurement method, device, equipment and storage medium, which can perform dynamic and accurate measurement of rigid bodies through monocular vision. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A schematic flow chart of a rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention;

[0051] Figure 2 A diagram for introducing a scene coordinate system applicable to a rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention;

[0052] Figure 3 A scene diagram of an experimental platform in a rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention;

[0053] Figure 4 A test comparison diagram of a rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention;

[0054] Figure 5 A test comparison diagram of a rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention;

[0055] Figure 6 A functional module diagram of a rigid body six-degree-of-freedom measurement device with real-time feedback provided by an embodiment of the present invention;

[0056] Figure 7 A schematic structural diagram of an electronic device for implementing the rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention.

[0057] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0058] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0059] The embodiment of the present application provides a rigid body six-degree-of-freedom measurement method with real-time feedback. In the embodiment of the present application, the execution subject of the rigid body six-degree-of-freedom measurement method with real-time feedback includes but is not limited to at least one of the electronic devices such as the server, the terminal, etc. that can be configured to execute the method provided by the embodiment of the present application. In other words, the rigid body six-degree-of-freedom measurement method with real-time feedback can be executed by software or hardware installed on a terminal device or a server device, and the software can be a blockchain platform. The server includes but is not limited to: a single server, a server cluster, a cloud server or a cloud server cluster, etc. The server can be an independent server, or it can be a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content delivery networks (Content Delivery Network, CDN), and big data and artificial intelligence platforms.

[0060] Reference Figure 1 FIG. 1 is a flow chart of a rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention. In this embodiment, the rigid body six-degree-of-freedom measurement method with real-time feedback includes:

[0061] S1. Use the pre-built checkerboard calibration plate to initialize the calibration operation of the pre-built monocular camera to obtain the initial camera internal and external parameters.

[0062] The checkerboard calibration plate is a commonly used tool in the fields of computer vision and photogrammetry, mainly used for camera calibration and geometric correction, and consists of a flat plate (such as cardboard, plastic or metal) and a black and white checkerboard pattern regularly arranged on its surface.

[0063] The monocular camera refers to a camera device that uses only one lens to capture images and obtains scene information through a single perspective.

[0064] The initial camera internal and external parameters refer to the parameters used to describe the camera imaging characteristics in the camera model, which are usually divided into two parts: internal parameters and external parameters. The internal parameters include focal length, principal point and distortion coefficient, while the external parameters are the position and direction of the camera in the world coordinate system, such as translation vector and rotation matrix.

[0065] In detail, in the embodiment of the present invention, the pre-built checkerboard calibration plate is used to perform an initialization calibration operation on the pre-built monocular camera to obtain the initial camera internal and external parameters, including:

[0066] Using a pre-built monocular camera, according to the preset multi-angle position information, a pre-built checkerboard calibration plate is used to obtain a calibration image sequence;

[0067] Performing a checkerboard corner point feature extraction operation on the calibration image sequence to obtain a corner point feature information set;

[0068] Acquire the size layout information of the checkerboard calibration plate, quantize the size layout information, and obtain a checkerboard layout feature vector;

[0069] By using a pre-built calibration algorithm, shooting parameters of the corner point feature information are identified according to the checkerboard layout feature vector to obtain initial camera internal and external parameters.

[0070] The multi-angle position information may be adaptively adjusted according to the rigid body type.

[0071] The chessboard corner points refer to the intersections formed at the junctions of black and white squares in the chessboard.

[0072] Specifically, in the embodiment of the present invention, the resolution of the monocular camera is 1280*720, the size of the checkerboard calibration plate is determined according to the actual situation, the checkerboard calibration plate is fixed in a stable position, and it is ensured to be clearly visible during the calibration process, and the image of the calibration plate is captured from multiple different perspectives using the monocular camera. When shooting, ensure that the distance, angle and lighting conditions between the camera and the calibration plate change to obtain rich calibration data, use image processing technology to extract the corner points of the checkerboard from each calibration image, use the camera imaging principle to calculate the camera's internal and external parameters, and calculate the error according to the reprojection formula to verify the accuracy of the calibration result.

[0073] S2. Obtain a rigid body with a preset chessboard marker attached thereto, and continuously capture and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image.

[0074] Specifically, refer to Figure 2 As shown, a checkerboard marker is attached to the rigid body to be measured, and these markers are always clearly visible during the movement of the rigid body. The number and arrangement of the markers should be selected according to the size and shape of the rigid body to ensure that enough feature points can be captured during the measurement process.

[0075] Furthermore, it is necessary to collect images of the rigid body with the markers attached.

[0076] In detail, in an embodiment of the present invention, the monocular camera is used to continuously capture and photograph the rigid body to obtain a rigid body historical image sequence and a rigid body real-time image, including:

[0077] Acquire the real-time captured image of the monocular camera in real time, and perform object recognition on the real-time captured image to obtain an object recognition result;

[0078] Determining whether a preset checkerboard marker object appears in the object recognition result;

[0079] When the checkerboard marker object appears in the object recognition result, the checkerboard marker object is recorded as a target to obtain a wall historical image video;

[0080] When a photography instruction is received from the user, the rigid body historical image video is intercepted to obtain a rigid body real-time image, and the video in the rigid body historical image video that is in a preset time period before the rigid body real-time image is collected according to a preset interception frequency to obtain a rigid body historical image sequence.

[0081] Specifically, in the embodiment of the present invention, the object recognition result depends on the scene during the rigid body detection, which may specifically include a flower pot, a fill light, a table, a checkerboard calibration plate, etc.

[0082] Specifically, in the embodiment of the present invention, the monocular camera is started, the preview mode is turned on, and the image sequence containing the checkerboard marker is continuously collected to obtain the rigid body historical image sequence, and the frame when the user's photography command is received is used as the rigid body real-time image. During the collection, it should be ensured that the camera's field of view can cover the entire rigid body, and interference factors such as lighting changes and occlusions should be minimized as much as possible.

[0083] S3. Extract a rigid body historical image from the rigid body historical image sequence in sequence, and perform image feature extraction on the rigid body historical image to obtain a rigid body marker feature set.

[0084] In detail, in the embodiment of the present invention, the image feature extraction of the rigid body historical image to obtain the rigid body marker feature set includes:

[0085] Graying the rigid body historical image to obtain a rigid body gray image, and performing Gaussian filtering and smoothing on the rigid body gray image to obtain a rigid body denoised gray image;

[0086] Performing a feature extraction operation on the rigid body denoised grayscale image to obtain a rigid body image feature set;

[0087] The rigid body image feature set is subjected to feature classification judgment based on preset markers to obtain a rigid body marker feature set.

[0088] The grayscale processing refers to the process of converting a color image into a grayscale image. A grayscale image is an image composed of pixels of different grayscale levels, and the value of each pixel represents its brightness without containing color information.

[0089] Among them, Gaussian filtering smoothing refers to a common image processing technology, which is mainly used to reduce noise and details in an image and make the image smoother. It usually uses the characteristics of the Gaussian function to perform weighted averaging on each pixel of the image to achieve a smoothing effect.

[0090] Wherein, the preset marker is a black and white grid distribution structure.

[0091] Specifically, in the embodiment of the present invention, for each frame of image, the above-mentioned image processing technology is used to extract the feature points of the checkerboard marker for subsequent matching with the feature points on the calibration plate.

[0092] S4. According to the pre-constructed minimization reprojection error algorithm and the rigid body marker feature set, the initial camera intrinsic and extrinsic parameters are dynamically adjusted to obtain dynamic camera intrinsic and extrinsic parameters, and the initial camera intrinsic and extrinsic parameters are updated using the dynamic camera intrinsic and extrinsic parameters.

[0093] Among them, the algorithm for minimizing the reprojection error is a method commonly used in the fields of computer vision and photogrammetry, mainly used for tasks such as camera calibration, 3D reconstruction and target tracking. Its basic idea is to optimize the reprojection error so that the projection position of the 3D point in the image is as close as possible to its corresponding image feature point.

[0094] In detail, in an embodiment of the present invention, the initial camera intrinsic and extrinsic parameters are dynamically adjusted according to the pre-constructed minimization reprojection error algorithm and the rigid body marker feature set to obtain dynamic camera intrinsic and extrinsic parameters, including:

[0095] Obtaining model size information of the rigid body;

[0096] Using a pre-built camera projection algorithm, according to the initial camera internal and external parameters and model size information, the rigid body is image predicted to obtain a rigid body prediction image;

[0097] According to a pre-built algorithm for minimizing reprojection errors, the difference between the rigid body marker feature set and the rigid body prediction image is calculated to obtain a reprojection error;

[0098] The reprojection error is minimized using a pre-constructed least squares method to obtain dynamic camera internal and external parameters.

[0099] Specifically, in an embodiment of the present invention, the model size information can be referenced by a car model. Then, the camera's intrinsic and extrinsic parameters are dynamically adjusted based on a reprojection error minimization algorithm using the matched rigid body marker feature set and the known chessboard size.

[0100] Further, in the embodiment of the present invention, the updating of the initial camera intrinsic and extrinsic parameters by using the dynamic camera intrinsic and extrinsic parameters includes:

[0101] The difference between the dynamic camera internal and external parameters and the initial camera internal and external parameters is calculated by using a pre-built incremental algorithm to obtain a parameter increment, wherein the incremental algorithm is expressed as:

[0102] P updated =P initial +α(P dynamic -P initial )

[0103] Where P updated represents the updated initial camera internal and external parameters, P initial represents the initial camera internal and external parameters, P dynamic represents the internal and external parameters of the dynamic camera, and α represents the smoothing factor ranging from 0 to 1;

[0104] The initial camera intrinsic and extrinsic parameters are weightedly calculated according to the parameter increment to obtain updated initial camera intrinsic and extrinsic parameters.

[0105] Specifically, in the embodiment of the present invention, an incremental calibration technology is used here to reduce the computational complexity and improve the real-time performance.

[0106] The embodiment of the present invention uses the calibration results of the previous frame or the previous frames as prior information to improve the accuracy and stability of the internal parameter adjustment, record the adjusted camera internal parameters, and update them to the processing of the next frame of image. This can ensure that the camera internal parameters are always kept up to date during the subsequent measurement process, thereby improving the accuracy of the measurement.

[0107] S5. After the traversal of the rigid body historical images in the rigid body historical image sequence is completed, image features are extracted from the rigid body real-time images to obtain a rigid body real-time feature set, and six-degree-of-freedom measurement is performed on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

[0108] First, the updated camera internal parameters are used to eliminate the distortion of each frame of the acquired image. The coordinate relationship before and after the radial distortion correction is:

[0109]

[0110] Tangential distortion requires two additional parameters to describe, and the coordinate relationship before and after correction is:

[0111]

[0112] In the formula, (x, y), are the ideal and distorted image coordinates respectively, and r is the distance from the image pixel to the center of the image, that is: r 2 =x 2 +y 2 .

[0113] Get feature points [uv] and checkerboard corner points [XY] from each frame of the image, combined with Zhang's camera calibration model Solve for the homography matrix H.

[0114] Combined with the updated camera intrinsic parameter A, according to:

[0115]

[0116] Solve the rotation matrix R = [r1 r2 r1×r2] and translation matrix T = [t X t Y t Z ]′.

[0117] Convert the calculated rotation matrix and translation matrix to the required spatial coordinate system, and calculate the rotation angle according to the formula:

[0118]

[0119] Finally, six degrees of freedom information is output.

[0120] Further, in an embodiment of the present invention, after obtaining the rigid body measurement result, the method further includes:

[0121] Using two cameras in a pre-built experimental platform to obtain real measurement results of the rigid body;

[0122] Performing difference calculation using the rigid body measurement result and the true measurement result to obtain a measurement difference;

[0123] Determining whether the measured difference is greater than a preset qualified threshold;

[0124] When the measured difference is greater than a preset qualified threshold, an alarm prompt message is generated.

[0125] The qualified threshold value may be configured according to specific circumstances. In the present invention, the qualified threshold value is configured to be 1%.

[0126] The alarm prompt information may be [re-measure the internal and external parameters of the camera].

[0127] like Figure 3As shown in FIG. 1 , an experimental platform is constructed in the embodiment of the present invention, and the platform is configured with two cameras. The setting of the two cameras is intended to verify the error performance of the method of the present invention in practical applications. Specifically, we use the method of the present invention to make a detailed measurement of the change of the six degrees of freedom of the all-terrain vehicle when it moves from near to far. After many tests: when the distance between the all-terrain vehicle and the camera changes, the relative error of its six degrees of freedom is as follows: Figure 4 and Figure 5 .

[0128] The accuracy of the method of the present invention is evaluated by measuring the relative error between the ATV and the camera at different distances. In the experiment, the ATV was placed at different distances in front of the camera, and the relative error of the vehicle body coordinate system in the world coordinate system was recorded.

[0129] From the images, we can see that the relative error increases as the distance between the ATV and the camera increases. This indicates that the accuracy of vision-based pose estimation methods may decrease when the distance between the target object (the ATV) and the camera increases. This may be due to a variety of factors, such as reduced image resolution, changes in lighting conditions, and distortion of the camera lens.

[0130] In practical applications, the distance between the target object and the camera needs to be adjusted according to the accuracy requirements.

[0131] The embodiment of the present invention first calibrates the parameters of the monocular camera through a checkerboard calibration plate to obtain the initial camera internal and external parameters, and then takes photos through a rigid body marked with a checkerboard marker; the present invention adopts a preview method to use the calibration results between shooting as prior information, continuously calculates the dynamic camera internal and external parameters, and updates the initial camera internal and external parameters, so that the final measurement process is more accurate. In addition, when updating the initial camera internal and external parameters, the present invention adopts an incremental algorithm instead of direct replacement, which greatly improves the stability of the initial camera internal and external parameters during the update process, making it less likely for the parameters to drift and cause measurement result deviations. Therefore, a real-time feedback rigid body six-degree-of-freedom measurement method provided by an embodiment of the present invention can be used to perform dynamic and accurate measurements of rigid bodies through monocular vision.

[0132] like Figure 6 , which is a functional module diagram of a rigid body six-degree-of-freedom measurement device with real-time feedback provided by an embodiment of the present invention.

[0133] The rigid body six-degree-of-freedom measurement device 100 with real-time feedback of the present invention can be installed in an electronic device. According to the functions to be implemented, the rigid body six-degree-of-freedom measurement device 100 with real-time feedback can include a camera parameter initialization module 101, a rigid body image acquisition module 102, a parameter real-time update module 103 and a rigid body measurement module 104. The module of the present invention can also be called a unit, which refers to a series of computer program segments that can be executed by an electronic device processor and can complete fixed functions, which are stored in the memory of the electronic device.

[0134] In this embodiment, the functions of each module / unit are as follows:

[0135] The camera parameter initialization module 101 is used to perform an initialization calibration operation on a pre-built monocular camera using a pre-built checkerboard calibration plate to obtain initial camera internal and external parameters;

[0136] The rigid body image acquisition module 102 is used to acquire the rigid body with the preset checkerboard marker attached thereto, and continuously capture and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image;

[0137] The parameter real-time updating module 103 is used to extract a rigid body historical image from the rigid body historical image sequence in turn, and perform image feature extraction on the rigid body historical image to obtain a rigid body marker feature set, and dynamically adjust the initial camera internal and external parameters according to a pre-built minimization reprojection error algorithm and the rigid body marker feature set to obtain dynamic camera internal and external parameters, and use the dynamic camera internal and external parameters to update the initial camera internal and external parameters;

[0138] The rigid body measurement module 104 is used to extract image features from the rigid body real-time images after traversing the rigid body historical images in the rigid body historical image sequence to obtain a rigid body real-time feature set, and perform six-degree-of-freedom measurement on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

[0139] In detail, each module described in the real-time feedback rigid body six-degree-of-freedom measurement device 100 described in the embodiment of the present application is used in the same manner as described above. Figures 1 to 5 The real-time feedback rigid body six-degree-of-freedom measurement method described in the invention has the same technical means and can produce the same technical effects, so it will not be repeated here.

[0140] like Figure 7 , which is a schematic diagram of the structure of an electronic device 1 for implementing a rigid body six-degree-of-freedom measurement method with real-time feedback provided by an embodiment of the present invention.

[0141] The electronic device 1 may include a processor 10, a memory 11, a communication bus 12 and a communication interface 13, and may also include a computer program stored in the memory 11 and executable on the processor 10, such as a rigid body six-degree-of-freedom measurement program with real-time feedback.

[0142] In some embodiments, the processor 10 may be composed of an integrated circuit, for example, a single packaged integrated circuit, or a plurality of packaged integrated circuits with the same or different functions, including one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and combinations of various control chips. The processor 10 is the control core (Control Unit) of the electronic device 1, and uses various interfaces and lines to connect various components of the entire electronic device, and executes or executes programs or modules stored in the memory 11 (for example, a rigid body six-degree-of-freedom measurement program that executes real-time feedback, etc.), and calls data stored in the memory 11 to execute various functions of the electronic device and process data.

[0143] The memory 11 includes at least one type of readable storage medium, and the readable storage medium includes flash memory, mobile hard disk, multimedia card, card-type memory (for example: SD or DX memory, etc.), magnetic memory, disk, optical disk, etc. In some embodiments, the memory 11 can be an internal storage unit of an electronic device, such as a mobile hard disk of the electronic device. In other embodiments, the memory 11 can also be an external storage device of an electronic device, such as a plug-in mobile hard disk, a smart memory card (SmartMedia Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device. Further, the memory 11 can also include both an internal storage unit of the electronic device and an external storage device. The memory 11 can not only be used to store application software and various types of data installed in the electronic device, such as the code of the rigid body six-degree-of-freedom measurement program with real-time feedback, but also can be used to temporarily store data that has been output or is to be output.

[0144] The communication bus 12 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The bus is configured to realize connection and communication between the memory 11 and at least one processor 10, etc.

[0145] The communication interface 13 is used for communication between the above-mentioned electronic device 1 and other devices, including a network interface and a user interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which is generally used to establish a communication connection between the electronic device and other electronic devices. The user interface may be a display (Display), an input unit (such as a keyboard (Keyboard)), and optionally, the user interface may also be a standard wired interface, a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, and an OLED (Organic Light-Emitting Diode, organic light-emitting diode) touch device, etc. Among them, the display may also be appropriately referred to as a display screen or a display unit, which is used to display information processed in the electronic device and to display a visual user interface.

[0146] Figure 7 Only an electronic device with components is shown, and those skilled in the art will understand that Figure 7 The structure shown does not constitute a limitation on the electronic device 1, and may include fewer or more components than shown in the figure, or combine certain components, or arrange the components differently.

[0147] For example, although not shown, the electronic device 1 may also include a power source (such as a battery) for supplying power to each component. Preferably, the power source may be logically connected to the at least one processor 10 through a power management device, so that the power management device can realize functions such as charging management, discharging management, and power consumption management. The power source may also include any components such as one or more DC or AC power sources, recharging devices, power failure detection circuits, power converters or inverters, power status indicators, etc. The electronic device 1 may also include a variety of sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be repeated here.

[0148] It should be understood that the embodiment is for illustration only and the scope of the patent application is not limited to this structure.

[0149] The real-time feedback rigid body six-degree-of-freedom measurement program stored in the memory 11 in the electronic device 1 is a combination of multiple instructions. When running in the processor 10, it can achieve:

[0150] Use the pre-built checkerboard calibration plate to initialize the calibration operation of the pre-built monocular camera to obtain the initial camera internal and external parameters;

[0151] Acquire a rigid body with a preset chessboard marker attached thereto, and continuously capture and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image;

[0152] Extracting a rigid body historical image from the rigid body historical image sequence in sequence, and performing image feature extraction on the rigid body historical image to obtain a rigid body marker feature set;

[0153] According to the pre-built minimization reprojection error algorithm and the rigid body marker feature set, the initial camera intrinsic and extrinsic parameters are dynamically adjusted to obtain dynamic camera intrinsic and extrinsic parameters, and the initial camera intrinsic and extrinsic parameters are updated using the dynamic camera intrinsic and extrinsic parameters;

[0154] After the rigid body historical images in the rigid body historical image sequence are traversed, image features are extracted from the rigid body real-time images to obtain a rigid body real-time feature set, and six-degree-of-freedom measurement is performed on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

[0155] Specifically, the specific implementation method of the processor 10 for the above instructions can refer to the description of the relevant steps in the corresponding embodiment of the accompanying drawings, which will not be repeated here.

[0156] Furthermore, if the module / unit integrated in the electronic device 1 is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. The computer-readable storage medium can be volatile or non-volatile. For example, the computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM).

[0157] The present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor of an electronic device, the computer program can implement:

[0158] Use the pre-built checkerboard calibration plate to initialize the calibration operation of the pre-built monocular camera to obtain the initial camera internal and external parameters;

[0159] Acquire a rigid body with a preset chessboard marker attached thereto, and continuously capture and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image;

[0160] Extracting a rigid body historical image from the rigid body historical image sequence in sequence, and performing image feature extraction on the rigid body historical image to obtain a rigid body marker feature set;

[0161] According to the pre-built minimization reprojection error algorithm and the rigid body marker feature set, the initial camera intrinsic and extrinsic parameters are dynamically adjusted to obtain dynamic camera intrinsic and extrinsic parameters, and the initial camera intrinsic and extrinsic parameters are updated using the dynamic camera intrinsic and extrinsic parameters;

[0162] After the rigid body historical images in the rigid body historical image sequence are traversed, image features are extracted from the rigid body real-time images to obtain a rigid body real-time feature set, and six-degree-of-freedom measurement is performed on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

[0163] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation.

[0164] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0165] In addition, each functional module in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0166] It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0167] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, so it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any attached figure mark in the claims should not be regarded as limiting the claims involved.

[0168] The blockchain referred to in this invention is a new application mode of computer technologies such as distributed data storage, peer-to-peer transmission, consensus mechanism, encryption algorithm, etc. Blockchain is essentially a decentralized database, a string of data blocks generated by cryptographic methods. Each data block contains a batch of network transaction information, which is used to verify the validity of its information (anti-counterfeiting) and generate the next block. Blockchain can include the underlying blockchain platform, platform product service layer, and application service layer.

[0169] The embodiments of the present application can acquire and process relevant data based on artificial intelligence technology. Among them, artificial intelligence (AI) is the theory, method, technology and application system that uses digital computers or machines controlled by digital computers to simulate, extend and expand human intelligence, perceive the environment, acquire knowledge and use knowledge to obtain the best results.

[0170] In addition, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices stated in the system claim can also be implemented by one unit or device through software or hardware. The words first, second, etc. are used to indicate names, and do not indicate any particular order.

[0171] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A real-time feedback rigid body six-degree-of-freedom measurement method, characterized in that: The method comprises: Use the pre-built checkerboard calibration plate to initialize the calibration operation of the pre-built monocular camera to obtain the initial camera internal and external parameters; Acquire a rigid body with a preset chessboard marker attached thereto, and continuously capture and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image; Extracting a rigid body historical image from the rigid body historical image sequence in sequence, and performing image feature extraction on the rigid body historical image to obtain a rigid body marker feature set; According to the pre-built minimization reprojection error algorithm and the rigid body marker feature set, the initial camera intrinsic and extrinsic parameters are dynamically adjusted to obtain dynamic camera intrinsic and extrinsic parameters, and the initial camera intrinsic and extrinsic parameters are updated using the dynamic camera intrinsic and extrinsic parameters; After the traversal of the rigid body historical images in the rigid body historical image sequence is completed, image features are extracted from the rigid body real-time images to obtain a rigid body real-time feature set, and six-degree-of-freedom measurement is performed on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

2. The rigid body six-degree-of-freedom measurement method with real-time feedback according to claim 1, characterized in that: The method of continuously capturing and photographing the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image includes: Acquire the real-time captured image of the monocular camera in real time, and perform object recognition on the real-time captured image to obtain an object recognition result; Determining whether a preset checkerboard marker object appears in the object recognition result; When the checkerboard marker object appears in the object recognition result, the checkerboard marker object is recorded as a target to obtain a wall historical image video; When a photography instruction is received from the user, the rigid body historical image video is intercepted to obtain a rigid body real-time image, and the video of the rigid body historical image video within a preset time period before the rigid body real-time image is collected according to a preset interception frequency to obtain a rigid body historical image sequence.

3. The rigid body six-degree-of-freedom measurement method with real-time feedback according to claim 1, characterized in that: The method of dynamically adjusting the initial camera internal and external parameters according to the pre-built minimization reprojection error algorithm and the rigid body marker feature set to obtain dynamic camera internal and external parameters includes: Obtaining model size information of the rigid body; Using a pre-built camera projection algorithm, according to the initial camera internal and external parameters and model size information, the rigid body is image predicted to obtain a rigid body prediction image; According to a pre-built algorithm for minimizing reprojection errors, the difference between the rigid body marker feature set and the rigid body prediction image is calculated to obtain a reprojection error; The reprojection error is minimized using a pre-constructed least squares method to obtain dynamic camera internal and external parameters.

4. The rigid body six-degree-of-freedom measurement method with real-time feedback according to claim 1, characterized in that: The updating of the initial camera internal and external parameters by using the dynamic camera internal and external parameters comprises: The difference between the dynamic camera internal and external parameters and the initial camera internal and external parameters is calculated by using a pre-built incremental algorithm to obtain a parameter increment, wherein the incremental algorithm is expressed as: P updated =P initial +α(P dynamic -P initial ) Where P updated represents the updated initial camera internal and external parameters, P initial represents the initial camera internal and external parameters, P dynamic represents the internal and external parameters of the dynamic camera, and α represents the smoothing factor ranging from 0 to 1; The initial camera intrinsic and extrinsic parameters are weightedly calculated according to the parameter increment to obtain updated initial camera intrinsic and extrinsic parameters.

5. The rigid body six-degree-of-freedom measurement method with real-time feedback according to claim 1, characterized in that: The pre-built checkerboard calibration plate is used to initialize and calibrate the pre-built monocular camera to obtain initial camera internal and external parameters, including: Using a pre-built monocular camera, according to the preset multi-angle position information, a pre-built checkerboard calibration plate is used to obtain a calibration image sequence; Performing a checkerboard corner point feature extraction operation on the calibration image sequence to obtain a corner point feature information set; Acquire the size layout information of the checkerboard calibration plate, quantize the size layout information, and obtain a checkerboard layout feature vector; By using a pre-built calibration algorithm, shooting parameters of the corner point feature information are identified according to the checkerboard layout feature vector to obtain initial camera internal and external parameters.

6. The rigid body six-degree-of-freedom measurement method with real-time feedback according to claim 1, characterized in that: The step of extracting image features from the rigid body historical image to obtain a rigid body marker feature set includes: Graying the rigid body historical image to obtain a rigid body gray image, and performing Gaussian filtering and smoothing on the rigid body gray image to obtain a rigid body denoised gray image; Performing a feature extraction operation on the rigid body denoised grayscale image to obtain a rigid body image feature set; The rigid body image feature set is subjected to feature classification judgment based on preset markers to obtain a rigid body marker feature set.

7. The rigid body six-degree-of-freedom measurement method with real-time feedback according to claim 1, characterized in that: After obtaining the rigid body measurement result, the method further includes: Using two cameras in a pre-built experimental platform to obtain real measurement results of the rigid body; Performing difference calculation using the rigid body measurement result and the true measurement result to obtain a measurement difference; Determining whether the measured difference is greater than a preset qualified threshold; When the measured difference is greater than a preset qualified threshold, an alarm prompt message is generated.

8. A rigid body six-degree-of-freedom measurement device with real-time feedback, characterized in that: The device comprises: The camera parameter initialization module is used to use the pre-built checkerboard calibration plate to initialize the calibration operation of the pre-built monocular camera to obtain the initial camera internal and external parameters; A rigid body image acquisition module is used to acquire a rigid body with a preset checkerboard marker attached thereto, and continuously acquire and photograph the rigid body using the monocular camera to obtain a rigid body historical image sequence and a rigid body real-time image; A parameter real-time updating module is used to extract a rigid body historical image from the rigid body historical image sequence in turn, and perform image feature extraction on the rigid body historical image to obtain a rigid body marker feature set, and dynamically adjust the initial camera internal and external parameters according to a pre-built minimization reprojection error algorithm and the rigid body marker feature set to obtain dynamic camera internal and external parameters, and use the dynamic camera internal and external parameters to update the initial camera internal and external parameters; The rigid body measurement module is used to extract image features of the rigid body real-time image after the traversal of the rigid body historical images in the rigid body historical image sequence is completed to obtain a rigid body real-time feature set, and to perform six-degree-of-freedom measurement on the rigid body real-time feature set according to the internal and external parameters of the dynamic camera to obtain a rigid body measurement result.

9. An electronic device, characterized in that: The electronic device comprises: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the rigid body six-degree-of-freedom measurement method with real-time feedback as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the real-time feedback rigid body six-degree-of-freedom measurement method as described in any one of claims 1 to 7 is implemented.

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