Measurement methods, systems, devices, and storage media

Abstract

The application provides a measurement method, system, device and storage medium, the method is realized by a measurement system, the measurement system comprises a laser ranging module, an image measurement module and a navigation module, the method comprises the following steps: obtaining measurement data of a to-be-measured point, the measurement data comprises first measurement data obtained from the laser ranging module, second measurement data obtained from the image measurement module and third measurement data obtained from the navigation module; at least one position measurement result of the to-be-measured point is calculated based on the measurement data of the to-be-measured point; the final position measurement result of the to-be-measured point is calculated based on the at least one position measurement result by using a preset measurement fusion algorithm. The effective fusion of the measurement data of the laser ranging module, the image measurement module and the navigation module improves the accuracy of the position measurement of the to-be-measured point in space.

Description

Measurement method, system, device and storage medium Technical Field

[0001] The present application relates to the field of data processing technology, and in particular to a measurement method, system, device and storage medium. Background Art

[0002] In the field of high-precision surveying and mapping, the use of inertial navigation RTK (Real Time Kinematic) receivers enables the measurement of points in three-dimensional space. RTK receivers that rely on a centering pole often have a limited measurement range due to the pole's length, and even cannot obtain measurement results when personnel cannot easily reach the measurement point. Laser RTK receivers that use a laser ranging module instead of a centering pole can overcome the pole length limitation and achieve contactless target point measurement. However, these receivers are susceptible to factors such as light intensity, receiver tilt angle, and operator jitter, resulting in significant differences in measurement accuracy at different operating distances.

[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to ordinary technicians in this field.

[0004] Summary of the Invention

[0005] In response to the problems in the prior art, the purpose of this application is to provide a measurement method, system, device and storage medium that effectively improves the accuracy of spatial point position measurement through data fusion of multi-source sensors.

[0006] The present invention provides a measurement method, comprising the following steps:

[0007] The method is implemented using a measurement system comprising a laser ranging module, an image measurement module and a navigation module. The method comprises the following steps:

[0008] Acquire measurement data of the point to be measured, the measurement data including first measurement data acquired from the laser ranging module, second measurement data acquired from the image measurement module, and third measurement data acquired from the navigation module;

[0009] Obtaining at least one position measurement result of the point to be measured by calculation based on the measurement data of the point to be measured;

[0010] A preset measurement fusion algorithm is used to calculate a final position measurement result of the point to be measured based on the at least one position measurement result.

[0011] In some embodiments, obtaining the measurement data of the point to be measured includes the following steps:

[0012] Acquire navigation information of the measurement system at each time from the navigation module;

[0013] Setting a plurality of shooting positions, and at each shooting position, obtaining distance information and captured images at corresponding moments from the laser ranging module and the image measurement module, respectively, with the distance information at the plurality of moments serving as the first measurement data and the captured images at the plurality of moments serving as the second measurement data;

[0014] determining a plurality of timestamps corresponding to the first measurement data and the second measurement data;

[0015] A plurality of navigation information at corresponding moments is acquired from the navigation module according to the plurality of timestamps of the first measurement data and the second measurement data as the third measurement data.

[0016] In some embodiments, obtaining the distance information and the captured image at corresponding moments from the image measurement module and the laser ranging module, respectively, comprises the following steps:

[0017] At each of the shooting positions, controlling the laser ranging module to emit laser light to illuminate the point to be measured;

[0018] The distance information is acquired from the laser distance measuring module by triggering a command, and at the same time, the image of the point to be measured is captured by the image measuring module.

[0019] In some embodiments, calculating and obtaining at least one position measurement result of the point to be measured based on the measurement data of the point to be measured includes the following steps:

[0020] Calculate at least one first position measurement result based on the first measurement data and the third measurement data;

[0021] At least one second position measurement result is calculated based on the second measurement data and the third measurement data.

[0022] In some embodiments, the navigation module includes an IMU sensor and a navigation unit, and the navigation information includes three-dimensional position information and attitude information of the IMU sensor;

[0023] Calculating at least one first position measurement result based on the first measurement data and the third measurement data includes the following steps:

[0024] Determine the three-dimensional coordinates of the IMU sensor in the geodetic coordinate system based on the three-dimensional position information of the IMU sensor

[0025] Get the coordinate conversion parameter D between the current navigation coordinate system and the geodetic coordinate system-1 ;

[0026] Determine the coordinate conversion parameters from the carrier coordinate system of the IMU sensor to the current navigation coordinate system based on the posture information of the IMU sensor

[0027] Get the projection coordinates of the position vector from the center of the IMU sensor to the laser emission point in the carrier coordinate system

[0028] Determine the projection coordinates of the position vector from the laser emission point to the point to be measured in the IMU carrier coordinate system based on the distance information

[0029] The first position measurement result is obtained by calculation.

[0030] In some embodiments, calculating at least one second position measurement result based on the second measurement data and the third measurement data comprises the following steps:

[0031] An image captured at a particular moment is selected as a reference image, and a camera coordinate system at a moment corresponding to a timestamp of the reference image is used as a reference coordinate system;

[0032] acquiring coordinate conversion parameters between the reference coordinate system and the earth coordinate system according to navigation information corresponding to the timestamp of the reference image;

[0033] Obtaining coordinate conversion parameters between a camera coordinate system at a time corresponding to the time stamp of each of the other captured images and the reference coordinate system based on navigation information at a time corresponding to the time stamp of each of the other captured images other than the reference image and navigation information corresponding to the time stamp of the reference image;

[0034] extracting the plane pixel coordinates of the laser irradiation points in the plurality of captured images;

[0035] Calculating the three-dimensional coordinates of the point to be measured in the reference coordinate system based on the plane pixel coordinates of the laser irradiation points in the plurality of captured images and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured images and the reference coordinate system;

[0036] According to the coordinate conversion parameters between the reference coordinate system and the geodetic coordinate system and the three-dimensional coordinates of the point to be measured in the reference coordinate system, the second measured three-dimensional coordinates of the point to be measured in the geodetic coordinate system are determined as the second position measurement result.

[0037] In some embodiments, the navigation module includes an IMU sensor and a navigation unit, and the navigation information includes three-dimensional position information and attitude information of the IMU sensor;

[0038] Acquiring coordinate conversion parameters between the reference coordinate system and the earth coordinate system according to navigation information corresponding to the timestamp of the reference image, comprising the following steps:

[0039] Obtaining coordinate conversion parameters between the carrier coordinate system of the IMU sensor and the camera coordinate system of the image measurement module;

[0040] Coordinate conversion parameters between the reference coordinate system and the earth coordinate system are determined based on the three-dimensional position information and posture information of the IMU sensor at the moment corresponding to the timestamp of the reference image.

[0041] In some embodiments, the step of calculating the three-dimensional coordinates of the point to be measured in the reference coordinate system based on the planar pixel coordinates of the laser irradiation points in the plurality of captured images and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured images and the reference coordinate system comprises the following steps:

[0042] For each of the captured images, respectively calculating the first three-dimensional coordinates of the point to be measured corresponding to the captured image in the reference coordinate system based on the plane pixel coordinates of the laser irradiation point in the captured image and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured image and the reference coordinate system;

[0043] Based on the plurality of the first three-dimensional coordinates, a triangulation method or a three-dimensional point cloud construction method is adopted to determine the three-dimensional coordinates of the point to be measured in the reference coordinate system.

[0044] In some embodiments, after calculating and obtaining at least one position measurement result of the point to be measured based on the measurement data of the point to be measured, and before calculating and obtaining a second position measurement result based on the second measurement data and the third measurement data, the method further includes the following steps:

[0045] determining, based on the first measurement data, whether the distance between the point to be measured and the measurement system is greater than or equal to a preset distance threshold;

[0046] If yes, calculating at least one second position measurement result based on the second measurement data and the third measurement data;

[0047] Otherwise, the second position measurement is not calculated.

[0048] In some embodiments, calculating at least one second position measurement result based on the second measurement data and the third measurement data comprises the following steps:

[0049] Screening each captured image in the second measurement data to eliminate captured images whose quality does not meet preset image quality requirements;

[0050] A second position measurement result is calculated based on the captured images that are not eliminated and the navigation information at the corresponding moment in the third measurement data.

[0051] In some embodiments, the step of using a preset measurement fusion algorithm to calculate the final position measurement result of the measured point based on the at least one position measurement result comprises the following steps:

[0052] performing weighted fusion on the first position measurement results corresponding to the plurality of moments based on a set first weight value to obtain a fused first position measurement result;

[0053] The fused first position measurement result and the second position measurement result are weightedly fused based on a set second weight value to obtain a final position measurement result of the point to be measured.

[0054] In some embodiments, the first position measurement results at multiple moments are weightedly fused based on a set first weight.

[0055] In some embodiments, the following steps are also included:

[0056] A second weight of the fused first position measurement result and the second position measurement result is set according to the image quality of the captured image corresponding to the second position measurement result.

[0057] The present application also provides a measurement system, which is characterized in that it is used to implement the measurement method, and the system includes:

[0058] Laser ranging module, image measurement module and navigation module;

[0059] A control module is configured to obtain measurement data of a point to be measured, the measurement data including first measurement data obtained from the laser ranging module, second measurement data obtained from the image measurement module, and third measurement data obtained from the navigation module; calculate at least one position measurement result of the point to be measured based on the measurement data of the point to be measured; and calculate a final position measurement result of the point to be measured based on the at least one position measurement result using a preset measurement fusion algorithm.

[0060] The present application also provides a measuring device, including:

[0061] case;

[0062] A laser ranging module is provided on the housing;

[0063] An image measurement module is provided on the housing, and a shooting direction of the image measurement module is consistent with a laser emission direction of the laser ranging module;

[0064] a navigation module, at least partially disposed within the housing, and an antenna of the navigation module disposed outside the housing;

[0065] A control module is disposed inside the housing and configured to execute the steps of the measurement method according to any one of claims 1 to 13.

[0066] An embodiment of the present application further provides a computer-readable storage medium for storing a program, which implements the steps of the measurement method when executed by a processor.

[0067] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

[0068] The measurement method, system, device, and storage medium of the present application have the following beneficial effects:

[0069] This application proposes a new measurement method for measuring the position of a spatial point to be measured. It is implemented using a measurement system that integrates a laser ranging module, an image measurement module, and a navigation module. Through the fusion processing of multi-source measurement data, the accuracy of the position measurement of the point to be measured at different distances is improved, and the influence of factors such as light intensity, the tilt angle of the measuring equipment, and the jitter of the operator during the measurement process is reduced, thereby ensuring the stability of the measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Other features, objects and advantages of the present application will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings.

[0071] FIG1 is a flow chart of a measurement method according to an embodiment of the present application;

[0072] FIG2 is a schematic structural diagram of a measurement system according to an embodiment of the present application;

[0073] FIG3 is a front view of a measuring device according to an embodiment of the present application;

[0074] FIG4 is a bottom view of a measuring device according to an embodiment of the present application;

[0075] FIG5 is a flow chart of obtaining measurement data of a point to be measured according to an embodiment of the present application;

[0076] FIG6 is a flow chart of calculating and obtaining at least one position measurement result of a point to be measured according to an embodiment of the present application;

[0077] FIG7 is a flowchart of calculating a final position measurement result of a point to be measured based on at least one position measurement result according to an embodiment of the present application. DETAILED DESCRIPTION

[0078] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be embodied in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0079] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices. Although "first" or "second" is used in this specification to indicate certain features, it is only to indicate the function and is not intended to limit the number and importance of specific features.

[0080] The flowcharts shown in the accompanying drawings are merely exemplary and do not necessarily include all steps. For example, some steps may be decomposed, while some steps may be combined or partially combined. Therefore, the actual execution order may change according to actual circumstances.

[0081] As shown in Figure 1, an embodiment of the present application provides a measurement method implemented using a measurement system, wherein the measurement system includes a laser ranging module, an image measurement module, and a navigation module. The measurement method includes the following steps:

[0082] S100: Acquire measurement data of a point to be measured, the measurement data including first measurement data acquired from the laser ranging module, second measurement data acquired from the image measurement module, and third measurement data acquired from the navigation module;

[0083] The first measurement data, the second measurement data, and the third measurement data respectively acquired by different measurement modules form multi-source measurement data, which are commonly used for subsequent measurement result calculation;

[0084] S200: Obtain at least one position measurement result of the point to be measured by calculation based on the measurement data of the point to be measured;

[0085] S300: Using a preset measurement fusion algorithm, calculate a final position measurement result of the point to be measured based on the at least one position measurement result.

[0086] Therefore, this application proposes a new measurement method for measuring the position of a spatial point to be measured, which is implemented using a measurement system that integrates a laser ranging module, an image measurement module and a navigation module. Through the fusion processing of multi-source measurement data, the accuracy of the position measurement of the point to be measured at different distances is improved, and the influence of factors such as light intensity, tilt angle of the measuring equipment and operator jitter during the measurement process is reduced, thereby ensuring the stability of the measurement accuracy.

[0087] As shown in FIG2 , an embodiment of the present invention further provides a measurement system for implementing the measurement method. The system includes:

[0088] Laser ranging module M100, image measurement module M200 and navigation module M300;

[0089] The control module M400 is configured to obtain measurement data of a point to be measured, the measurement data including first measurement data obtained from the laser ranging module M100, second measurement data obtained from the image measurement module M200, and third measurement data obtained from the navigation module M300; calculate at least one position measurement result of the point to be measured based on the measurement data of the point to be measured; and calculate a final position measurement result of the point to be measured based on the at least one position measurement result using a preset measurement fusion algorithm.

[0090] This application is implemented by adopting this measurement system, which integrates a laser ranging module, an image measurement module and a navigation module. Through the fusion processing of multi-source measurement data, the accuracy of the position measurement of the measured point is improved, and the influence of factors such as light intensity, tilt angle of the measuring equipment and operator jitter during the measurement process is reduced, thereby ensuring the stability of the measurement accuracy.

[0091] An embodiment of the present invention further provides a measuring device, comprising:

[0092] case;

[0093] A laser ranging module is provided on the housing;

[0094] An image measurement module is provided on the housing, and a shooting direction of the image measurement module is consistent with a laser emission direction of the laser ranging module;

[0095] a navigation module, at least partially disposed inside the housing, and an antenna of the navigation module disposed outside the housing, for example, the navigation module includes a GNSS module, an IMU sensor, and an antenna, and the GNSS module and the IMU sensor are disposed inside the housing;

[0096] The control module is disposed inside the housing and is configured to execute the steps in the measurement method by executing the executable instructions.

[0097] Figures 3 and 4 are schematic diagrams of the measuring device of this embodiment. The measuring device comprises a housing 1, a navigation module 2, an image measurement module 4, a laser ranging module 5, and a control module 7. A linkage trigger device 3 is provided on the surface of the housing 1. A centering rod connection hole 6 is also provided on the housing 1 for connection to the centering rod. The measuring device utilizes an integrated design, is compact, and consumes low power, making it easy to carry and operate for extended periods.

[0098] The navigation module 2 adopts a GNSS / INS combined navigation module, where GNSS stands for Global Navigation Satellite System and INS stands for Inertial Navigation System. The navigation module 2 includes a navigation unit and an IMU (Inertial Measurement Unit) sensor. The navigation unit includes a GNSS antenna, a radio frequency front end, a Kalman filter and a CPU processor. The IMU sensor includes a three-axis accelerometer and a three-axis gyroscope. The navigation module 2 sends the high-frequency attitude observation values ​​and GNSS observation values ​​of the IMU sensor to the CPU processor, respectively realizing the mechanical arrangement of the inertial navigation system and the RTK solution of the satellite navigation system, and further fuses the solution results through the Kalman filter to obtain the high-frequency position and attitude information of the IMU sensor, that is, to obtain navigation information.

[0099] The linkage trigger device 3 can be a button or touchscreen. When operated, it simultaneously triggers the laser ranging module 5 to measure distance and the image measurement module 4 to take photos. The image measurement module 4 can be a camera, specifically comprising a lens, a photosensitive chip, an A / D converter, and a digital information processing chip. The laser ranging module 5 comprises a single-line laser rangefinder and a CPU processor. By illuminating a laser spot onto a point to be measured in space, it acquires phase difference observations when triggered by the linkage trigger device 3. The CPU processes these observations to obtain distance information between the point to be measured and the laser emission point. The image measurement module 4's shooting direction aligns with the laser emission direction of the laser ranging module 5, enabling the image measurement module 4 and the laser ranging module 5 to simultaneously acquire distance information and take photos when triggered simultaneously.

[0100] As shown in FIG5 , in this embodiment, the step S100 of obtaining measurement data of the point to be measured includes the following steps:

[0101] S110: Acquire navigation information of the measurement system at each time from the navigation module;

[0102] The navigation module is used to obtain navigation information at various times in real time, and each navigation information is timestamped with the time of acquisition;

[0103] The step S110 specifically includes: turning on the navigation module on an open surface, configuring the navigation module and accessing differential data to obtain RTK high-precision three-dimensional position and velocity information. Then, the following steps are used to initialize the navigation module: first, the receiver is stationary for a few seconds to obtain the initial values ​​of the roll angle and pitch angle of the IMU sensor relative to the local navigation coordinate system, and then the measurement device is shaken to initialize the heading angle of the IMU sensor relative to the local navigation coordinate system, so that the GNSS / INS combined navigation module is successfully initialized; the local navigation coordinate value here refers to the local geographic horizontal coordinate system (Local Level Frame, LLF), which can provide intuitive navigation parameters. The origin of the coordinate system is the center of the carrier, the x-axis points to the north along the tangent direction of the reference ellipsoid meridian, the y-axis is vertically downward along the normal of the reference ellipsoid, and the z-axis forms a right-handed coordinate system with the x-axis and the y-axis in the local horizontal plane; in this embodiment, the carrier is a measurement device equipped with an IMU sensor;

[0104] Initializing the navigation module here may also include the following steps: randomly selecting a fixed point on an open surface, tilting a certain angle above the selected fixed point, generally in the front, back, left, and right directions, irradiating the laser point of the laser ranging module on the fixed point, obtaining multiple distance information from the laser ranging module emission point to the fixed point, using the distance information to calculate the initial heading angle of the IMU sensor relative to the local navigation coordinate system, and completing the initialization of the GNSS / INS integrated navigation module;

[0105] After the navigation module is initialized, the RTK 3D position and velocity information and the IMU sensor mechanical arrangement results are continuously fed into the Kalman filter to obtain high-frequency IMU 3D position and attitude information, that is, real-time navigation information;

[0106] S120: Setting a plurality of shooting positions. At each shooting position, obtaining distance information and a captured image at a corresponding moment from the laser ranging module and the image measurement module, respectively. The distance information at the plurality of moments is used as the first measurement data, and the captured images at the plurality of moments is used as the second measurement data.

[0107] Specifically, the shooting position and time can correspond one-to-one, or multiple distance information and multiple captured images can be obtained for each shooting position, that is, the shooting position and time are in a one-to-many relationship, but the time, distance information, and captured images are in a one-to-one correspondence;

[0108] Taking setting two shooting positions as an example, step S120 may specifically include the following steps:

[0109] At a first position, the laser ranging module is controlled to illuminate the laser point onto the point to be measured. The linkage trigger device is pressed, and the laser ranging module and the image measurement module respectively collect distance information and capture images corresponding to the point to be measured. The laser ranging module and the image measurement module respectively attach time stamp information to the collected distance information and the captured images based on the PPS (Pulse Per Second) signal;

[0110] Similarly, at the second position, the specific steps at the first position can be followed to complete the acquisition of distance information and captured images of the same point to be measured at the second position, and the collected distance information and captured images are attached with the timestamp information of the time of acquisition at the second position. The images captured at the selected second position and the first position should generally have a certain parallax. It is also possible to select multiple shooting positions to perform the measurement process described above on the above-mentioned point to be measured, and obtain distance information and captured images with timestamp information collected at multiple shooting positions;

[0111] S130: Determine multiple timestamps corresponding to the first measurement data and the second measurement data;

[0112] S140: Acquire, from the navigation module, multiple navigation information at corresponding moments according to multiple timestamps of the first measurement data and the second measurement data, as the third measurement data. Therefore, the third measurement data also includes navigation information at multiple moments, and the timestamps of the third measurement data correspond to the timestamps of the first measurement data and the second measurement data.

[0113] The timestamp here is the timestamp of each moment when the distance information and the captured image are obtained. The navigation information corresponding to the time stamp is obtained from the navigation module, so that the IMU position and attitude information obtained by the navigation module, the distance information obtained by the laser ranging module, and the captured image obtained by the image measurement module have the same time reference.

[0114] In this embodiment, the step S120 of acquiring the distance information and the captured image at corresponding moments from the image measurement module and the laser ranging module respectively includes the following steps:

[0115] At each of the shooting positions, controlling the laser ranging module to emit laser light to illuminate the point to be measured;

[0116] The laser distance measurement module acquires the distance information through a trigger instruction, and at the same time, the image measurement module captures the image of the point to be measured. The trigger instruction can be issued by pressing a physical button or from a mobile terminal carried by the user.

[0117] As shown in FIG6 , in this embodiment, the step S200 of calculating and obtaining at least one position measurement result of the point to be measured based on the measurement data of the point to be measured includes the following steps:

[0118] S210: Obtain at least one first position measurement result by calculation based on the first measurement data and the third measurement data;

[0119] S230: Calculate and obtain at least one second position measurement result based on the second measurement data and the third measurement data.

[0120] As described above, the navigation module includes an IMU sensor and a navigation unit, and the navigation information includes three-dimensional position information and attitude information of the IMU sensor. Step S210: calculating at least one first position measurement result based on the first measurement data and the third measurement data includes the following steps:

[0121] Determine the three-dimensional coordinates of the IMU sensor in the geodetic coordinate system based on the three-dimensional position information of the IMU sensor The three-dimensional position information of the IMU sensor obtained from the navigation module is the three-dimensional coordinates of the IMU sensor in the geodetic coordinate system;

[0122] Get the coordinate conversion parameter D between the current navigation coordinate system and the geodetic coordinate system -1 Here, the coordinate conversion parameter D between the current navigation coordinate system and the geodetic coordinate system can be calculated based on the three-dimensional position information of the IMU sensor and the inherent parameters of the earth reference ellipsoid -1 (including translation matrix and rotation matrix), or directly obtain the pre-configured coordinate conversion parameters D between the current navigation coordinate system and the earth coordinate system according to the type of navigation module -1 ;

[0123] Determine the coordinate conversion parameters from the carrier coordinate system of the IMU sensor to the current navigation coordinate system based on the posture information of the IMU sensor (including translation matrix and rotation matrix); Here, the carrier coordinate system refers to an orthogonal coordinate system fixed to the carrier, the x-axis is in the same direction as the roll axis of the carrier's angular motion and points to the front of the carrier, the y-axis is in the same direction as the pitch axis of the carrier's angular motion and points to the right of the carrier, and the z-axis is in the same direction as the yaw axis of the carrier's angular motion and forms a right-handed coordinate system with the x-axis and y-axis;

[0124] Get the projection coordinates of the position vector from the center of the IMU sensor to the laser emission point in the carrier coordinate system Here the projection coordinates The external parameters of the IMU sensor and the laser ranging module can be obtained by calibrating the software (including the coordinate conversion parameters between the carrier coordinate system of the IMU sensor and the laser coordinate system of the laser ranging module, including the translation matrix and the rotation matrix). The distance between the IMU sensor and the laser ranging module can also be obtained by measuring the distance between them with a ruler, or by measuring the structural design drawings of the measuring equipment. Specifically, the three-dimensional coordinates of the laser emission point in the laser coordinate system are converted into the three-dimensional coordinates in the carrier coordinate system.

[0125] Determine the projection coordinates of the position vector from the laser emission point to the point to be measured in the IMU carrier coordinate system based on the distance information Here The acquisition method can be: obtaining the distance information between the point to be measured and the laser emission point through the laser ranging module, obtaining the three-dimensional coordinates of the point to be measured in the laser coordinate system, and converting the three-dimensional coordinates of the point to be measured in the laser coordinate system into the carrier coordinate system of the IMU sensor through the external parameters of the IMU sensor and the laser rangefinder;

[0126] The first position measurement result is calculated using the following formula:

[0127] in, is the first measured three-dimensional coordinate of the point to be measured in the geodetic coordinate system, which serves as the first position measurement result.

[0128] In this embodiment, the step S220 of calculating and obtaining at least one second position measurement result based on the second measurement data and the third measurement data includes the following steps:

[0129] (1) Calibrate the internal parameters of the image measurement module. The camera internal parameters of the image measurement module can be obtained by calibrating the camera calibration platform using a chessboard or AprilGrid calibration plate. The camera internal parameters mainly include resolution (such as 1920×1080), coordinate conversion parameters between the UV coordinate system and the pixel coordinate system, and the size of the photosensitive chip;

[0130] (2) Selecting any one of the multiple images captured by the image measurement module as a reference image to initialize the image measurement; specifically including:

[0131] Select an image captured at a specific moment as the reference image, and use the camera coordinate system at the time corresponding to the timestamp of the reference image as the reference coordinate system. The camera coordinate system here refers to the coordinate system based on the image measurement module. Its coordinate origin is the center of the optical lens of the image measurement module. The x-axis points to the right along the direction of the camera lens, the z-axis points forward along the direction of the camera lens, and the y-axis, x-axis, and z-axis form a right-handed coordinate system.

[0132] Coordinate conversion parameters between the reference coordinate system and the earth coordinate system are obtained according to the navigation information corresponding to the timestamp of the reference image.

[0133] In this embodiment, obtaining coordinate conversion parameters between the reference coordinate system and the earth coordinate system according to the navigation information corresponding to the timestamp of the reference image includes the following steps:

[0134] Calibrate the external parameters of the IMU sensor and the image measurement module, the external parameters including the coordinate conversion parameters between the carrier coordinate system of the IMU sensor and the image measurement module, including the rotation matrix and the translation matrix;

[0135] The coordinate conversion parameters between the carrier coordinate system of the IMU sensor and the earth coordinate system are determined by combining the external parameters of the IMU sensor and the image measurement module to determine the conversion parameters between the reference coordinate system and the earth coordinate system, including the translation matrix and the rotation matrix.

[0136] (3) obtaining coordinate conversion parameters between the camera coordinate system at the time corresponding to the time stamp of each of the other captured images and the reference coordinate system based on the navigation information at the time corresponding to the time stamp of the other captured images other than the reference image and the navigation information corresponding to the time stamp of the reference image, including a translation matrix and a rotation matrix; wherein the coordinate conversion parameters can also be obtained by a VIO (Visual Inertial Odometry) method, which is a technology for measuring sensor states using one or more cameras and one or more IMU sensors, or can also be obtained by using a VO (Visual Odometry) method after determining a monocular scale factor;

[0137] (4) extracting the planar pixel coordinates of the laser irradiation points in the plurality of captured images;

[0138] Specifically, the laser emitted by the laser ranging module illuminates the red background formed on the point to be measured, and the plane pixel coordinates of the point to be measured are extracted from each captured image. This may include extracting the plane pixel coordinates of the point to be measured in other captured images except the reference image, or extracting the plane pixel coordinates of the point to be measured in each captured image including the reference image;

[0139] The plane pixel coordinates can be directly extracted by a feature point extraction algorithm, or obtained by extracting several closest similar feature points and then manually screening them, or obtained by manually selecting them after magnifying the image, thereby determining the pixel coordinates corresponding to the point to be measured.

[0140] (5) Calculating the three-dimensional coordinates of the point to be measured in the reference coordinate system based on the planar pixel coordinates of the laser irradiation points in the plurality of captured images and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured images and the reference coordinate system.

[0141] In this embodiment, the method of calculating the three-dimensional coordinates of the point to be measured in the reference coordinate system based on the planar pixel coordinates of the laser irradiation points in the plurality of captured images and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured images and the reference coordinate system comprises the following steps:

[0142] For each of the captured images, respectively calculating the first three-dimensional coordinates of the point to be measured corresponding to the captured image in the reference coordinate system based on the plane pixel coordinates of the laser irradiation point in the captured image and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured image and the reference coordinate system;

[0143] Based on the plurality of the first three-dimensional coordinates, a triangulation method or a three-dimensional point cloud construction method is adopted to determine the three-dimensional coordinates of the point to be measured in the reference coordinate system.

[0144] Specifically, based on the plane pixel coordinates of the point to be measured extracted on the plane of the captured image, the calibrated camera intrinsic parameters, and the coordinate system transformation relationship between the camera coordinate system at the time corresponding to the timestamp of the captured image and the reference coordinate system, a triangulation method is used to calculate the three-dimensional coordinates of the point to be measured in the reference coordinate system. If the image measurement module captures more than two images, the SFM (Structure From Motion) method can also be used to generate three-dimensional point cloud information around the point to be measured, and then the three-dimensional coordinates of the point to be measured in the reference coordinate system are determined based on the three-dimensional point cloud information. The triangulation method here refers to the following: in the field of photogrammetry, a single image cannot recover the three-dimensional coordinates of an image point, and at least two images are required to obtain the true coordinates of a pixel point. Triangulation determines the distance to the same location point by observing the angle between two shooting positions, thereby obtaining depth information and further determining the true coordinates. SFM is a technology for estimating three-dimensional structure from a series of multiple two-dimensional image sequences containing visual motion information.

[0145] (6) Determine the second measured three-dimensional coordinates of the point to be measured in the geodetic coordinate system as the second position measurement result based on the coordinate conversion parameters between the reference coordinate system and the geodetic coordinate system and the three-dimensional coordinates of the point to be measured in the reference coordinate system.

[0146] Therefore, in this embodiment, by illuminating the measured point with a laser beam, creating a red background, during capture, the laser point can be used directly as an image feature point, providing distinct characteristic information. This eliminates the need for complex feature point extraction and matching algorithms for impact measurement, saving computing resources while ensuring computational timeliness. The user simply controls the linkage trigger to simultaneously capture distance information and capture an image, making operation very convenient.

[0147] In this embodiment, the combination of navigation information, distance information, and image information can accurately measure the position of the test point, and is particularly suitable for measuring the position of a long-distance spatial test point. In one embodiment, when using this measurement method to measure the position of a close-range spatial test point, due to the close distance, the measurement is less likely to be affected by other factors. The navigation information and distance information can also achieve high-precision position measurement. In this case, there is no need to process the captured image, which saves image processing time and improves the speed of position result solution.

[0148] Specifically, as shown in FIG6 , in this embodiment, after the step S200 of calculating and obtaining at least one position measurement result of the point to be measured based on the measurement data of the point to be measured, before the step S230, the following steps are further included:

[0149] S220: Determine whether the distance between the measured point and the measurement system is greater than or equal to a preset distance threshold according to the first measurement data;

[0150] If yes, it indicates that the position measurement is for the remote measured point, and the process proceeds to step S230: at least one second position measurement result is calculated based on the second measurement data and the third measurement data, and position result fusion is performed using the at least one first position measurement result and the at least one second position measurement result in a subsequent step S300;

[0151] Otherwise, S240: indicating that the position measurement is for a short-distance point to be measured, the second position measurement result is not calculated, and the position result fusion is performed directly using the at least one first position measurement result obtained.

[0152] When the point to be measured is far away, when holding the measuring device to collect distance information and capture images, the hand may shake, making it difficult for the laser point to illuminate the point to be measured in the three-dimensional space, or the environment in which the image is captured may be too bright or too dark, resulting in poor image quality and difficulty in extracting feature points. In this case, the captured images can be adaptively screened to eliminate images with poor quality to avoid introducing inaccurate position measurement results. In this embodiment, step S230: calculating at least one second position measurement result based on the second measurement data and the third measurement data includes the following steps:

[0153] Screening each captured image in the second measurement data to eliminate captured images whose quality does not meet preset image quality requirements;

[0154] A second position measurement result is calculated based on the captured images that are not eliminated and the navigation information at the corresponding moment in the third measurement data.

[0155] The quality score of the image captured here can be manually scored by the staff, or a preset image quality scoring model can be used to score the image quality, or several quality scoring indicators can be set: brightness, clarity, contrast, whether the test point is visible, etc., and scored separately and then weighted to calculate the total score.

[0156] As shown in FIG7 , in this embodiment, step S300 , which uses a preset measurement fusion algorithm to calculate the final position measurement result of the point to be measured based on the at least one position measurement result, includes the following steps:

[0157] S310: performing weighted fusion on the first position measurement results corresponding to the plurality of moments based on a set first weight value to obtain a fused first position measurement result; wherein the weighted fusion is to weightedly average the three-dimensional position coordinates in the first position measurement results at each moment to obtain a three-dimensional position coordinate;

[0158] S320: Perform weighted fusion on the fused first position measurement result and the second position measurement result based on a set second weight value to obtain a final position measurement result of the point to be measured; the weighted fusion here is to weightedly average the three-dimensional position coordinates in the fused first position measurement result and the second position measurement result to obtain a final three-dimensional position coordinate as the final position measurement result.

[0159] In this embodiment,

[0160] The first position measurement results at the multiple moments are weightedly fused based on the corresponding first weights using the following formula:

[0161] Among them, P is the first position measurement result after fusion, P i is the first position measurement result at the i-th moment, w i is the first weight of the first position measurement result at the i-th moment, and satisfies:

[0162] Where i∈[1,n], n is the number of moments corresponding to the first position measurement result obtained, s i is the distance information at the i-th moment.

[0163] In this embodiment, the following steps are also included:

[0164] A second weight of the fused first position measurement result and the second position measurement result is set according to the image quality of the captured image corresponding to the second position measurement result.

[0165] For example, the second weights of the fused first position measurement result and the second position measurement result can be determined based on the image quality score. For example, when the image quality score is less than the first preset score threshold, the second weight of the second position measurement result is set to 0, and the second weight of the fused first position measurement result is set to 1. If the image quality score is between the first preset score threshold and the second preset score threshold, the second weight of the first position measurement result is set to 0.7, and the second weight of the second position measurement result is set to 0.3. If the image quality score is greater than the second preset score threshold, the second weight of the first position measurement result is set to 0.5, and the second weight of the second position measurement result is set to 0.5. The method of setting the second weight here is only an example. In other implementation methods, other setting methods may also be used, all of which fall within the scope of protection of this application.

[0166] Therefore, in this embodiment, by fusing the measurement data of multiple sources of sensors and screening and fusing the measurement results based on the distance to the measured point, the quality of the measurement data, and the quality of the captured image, the optimal position measurement result can be output, effectively avoiding the influence of hand shake, weather conditions, or other interference on the position measurement accuracy, thereby improving the position measurement accuracy.

[0167] The present application also provides a computer-readable storage medium for storing a program that, when executed by a processor, implements the steps of the measurement method. In some possible implementations, various aspects of the present application may also be implemented in the form of a program product, which includes program code. When the program product is executed on a terminal device, the program code is used to cause the terminal device to perform the steps described in the measurement method section above according to the various exemplary embodiments of the present application.

[0168] According to an embodiment of the present application, a program product for implementing the above method can be a portable compact disc read-only memory (CD-ROM) and include program code, and can be executed on a terminal device, such as a personal computer. However, the program product of the present application is not limited thereto. In this document, a readable storage medium can be any tangible medium containing or storing a program, which can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0169] The program product may be implemented in any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or component, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0170] The computer-readable storage medium may include a data signal propagated in baseband or as part of a carrier wave, wherein the readable program code is carried. The data signal propagated may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The readable storage medium may also be any readable medium other than a readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or component. The program code contained on the readable storage medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination thereof.

[0171] The program code for performing the operations of the present application can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code can be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0172] When the program in the computer storage medium is executed by the processor, the steps of the measurement method are implemented. Therefore, the computer storage medium can also obtain the technical effects of the above-mentioned measurement method.

[0173] The above content is a further detailed description of the present application in conjunction with specific preferred embodiments, and the specific implementation of the present application cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, and all of them should be considered to fall within the scope of protection of the present application.

Claims

1. A measurement method, characterized in that: The method is implemented by using a measurement system, the measurement system includes a laser ranging module, an image measurement module and a navigation module, and the method includes the following steps: Acquire measurement data of the point to be measured, the measurement data comprising first measurement data acquired from the laser ranging module, second measurement data acquired from the image measurement module, and third measurement data acquired from the navigation module; Calculate at least one position measurement result of the point to be measured based on the measurement data of the point to be measured; A preset measurement fusion algorithm is adopted to calculate a final position measurement result of the point to be measured based on the at least one position measurement result.

2. The measuring method according to claim 1, characterized in that: The step of obtaining the measurement data of the point to be measured comprises the following steps: Acquire navigation information of the measurement system at each time from the navigation module; Setting a plurality of shooting positions, at each shooting position, respectively obtaining distance information and shooting images at corresponding moments from the laser ranging module and the image measuring module, the distance information at the plurality of moments being used as the first measurement data, and the shooting images at the plurality of moments being used as the second measurement data; Determining a plurality of timestamps corresponding to the first measurement data and the second measurement data; Acquire multiple navigation information at corresponding moments from the navigation module according to multiple timestamps of the first measurement data and the second measurement data as the third measurement data.

3. The measuring method according to claim 2, characterized in that: Acquiring the distance information and the captured image at the corresponding time from the image measurement module and the laser distance measurement module respectively comprises the following steps: At each of the shooting positions, controlling the laser ranging module to emit laser light to illuminate the point to be measured; The distance information is acquired from the laser distance measuring module by triggering the instruction, and at the same time, the image of the point to be measured is collected by the image measuring module.

4. The measuring method according to claim 2, characterized in that: Calculating at least one position measurement result of the point to be measured based on the measurement data of the point to be measured includes the following steps: Calculate at least one first position measurement result based on the first measurement data and the third measurement data; At least one second position measurement result is calculated based on the second measurement data and the third measurement data.

5. The measuring method according to claim 4, characterized in that: The navigation module includes an IMU sensor and a navigation unit, and the navigation information includes three-dimensional position information and attitude information of the IMU sensor; Calculating at least one first position measurement result based on the first measurement data and the third measurement data comprises the following steps: Determine the three-dimensional coordinates of the IMU sensor in the geodetic coordinate system according to the three-dimensional position information of the IMU sensor Get the coordinate conversion parameters D between the current navigation coordinate system and the earth coordinate system -1 ; Determine the coordinate conversion parameters from the carrier coordinate system of the IMU sensor to the current navigation coordinate system according to the posture information of the IMU sensor Obtain the projection coordinates of the position vector pointing from the center of the IMU sensor to the laser emission point in the carrier coordinate system Determine the projection coordinates of the position vector from the laser emission point to the point to be measured in the IMU carrier coordinate system according to the distance information The first position measurement result is obtained by calculation.

6. The measuring method according to claim 4, characterized in that: Calculating at least one second position measurement result based on the second measurement data and the third measurement data comprises the following steps: Selecting an image captured at a moment as a reference image, and using the camera coordinate system at the moment corresponding to the timestamp of the reference image as a reference coordinate system; Acquire coordinate conversion parameters between the reference coordinate system and the earth coordinate system according to the navigation information corresponding to the timestamp of the reference image; Obtaining coordinate conversion parameters between a camera coordinate system at a time corresponding to the timestamp of each of the other captured images and the reference coordinate system according to navigation information at a time corresponding to the timestamp of the other captured images except the reference image and navigation information corresponding to the timestamp of the reference image; extracting the plane pixel coordinates of the laser irradiation points in the plurality of captured images; Calculate the three-dimensional coordinates of the point to be measured in the reference coordinate system based on the plane pixel coordinates of the laser irradiation points in the plurality of captured images and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured images and the reference coordinate system; According to the coordinate conversion parameters between the reference coordinate system and the geodetic coordinate system and the three-dimensional coordinates of the measured point in the reference coordinate system, the second measured three-dimensional coordinates of the measured point in the geodetic coordinate system are determined as the second position measurement result.

7. The measuring method according to claim 6, characterized in that: The navigation module includes an IMU sensor and a navigation unit, and the navigation information includes three-dimensional position information and attitude information of the IMU sensor; Acquiring coordinate conversion parameters between the reference coordinate system and the earth coordinate system according to navigation information corresponding to the timestamp of the reference image, comprising the following steps: Obtaining coordinate conversion parameters between the carrier coordinate system of the IMU sensor and the camera coordinate system of the image measurement module; Based on the three-dimensional position information and posture information of the IMU sensor at the time corresponding to the timestamp of the reference image, coordinate conversion parameters between the reference coordinate system and the earth coordinate system are determined.

8. The measuring method according to claim 6, characterized in that: The method of calculating the three-dimensional coordinates of the point to be measured in the reference coordinate system based on the plane pixel coordinates of the laser irradiation points in the plurality of captured images and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured images and the reference coordinate system comprises the following steps: For each of the captured images, based on the plane pixel coordinates of the laser irradiation point in the captured image and the coordinate conversion parameters between the camera coordinate system at the moment corresponding to the timestamp of the captured image and the reference coordinate system, respectively calculate the first three-dimensional coordinates of the point to be measured corresponding to the captured image in the reference coordinate system; Based on the first three-dimensional coordinates, a triangulation method or a three-dimensional point cloud construction method is used to determine the three-dimensional coordinates of the point to be measured in the reference coordinate system.

9. The measuring method according to claim 4, characterized in that: After calculating and obtaining at least one position measurement result of the point to be measured based on the measurement data of the point to be measured, and before calculating and obtaining a second position measurement result based on the second measurement data and the third measurement data, the following steps are also included: Determining whether the distance between the point to be measured and the measurement system is greater than or equal to a preset distance threshold according to the first measurement data; If yes, calculating at least one second position measurement result based on the second measurement data and the third measurement data; Otherwise, the second position measurement is not calculated.

10. The measuring method according to claim 4, characterized in that: Calculating at least one second position measurement result based on the second measurement data and the third measurement data comprises the following steps: Screening each captured image in the second measurement data to eliminate captured images whose quality does not meet preset image quality requirements; The second position measurement result is calculated based on the captured image that is not eliminated and the navigation information at the corresponding moment in the third measurement data.

11. The measuring method according to claim 4, characterized in that: The method of using a preset measurement fusion algorithm to calculate the final position measurement result of the point to be measured based on the at least one position measurement result comprises the following steps: Performing weighted fusion on the first position measurement results corresponding to the plurality of the moments based on a set first weight value to obtain a fused first position measurement result; The fused first position measurement result and the second position measurement result are weighted-fused based on a set second weight value to obtain a final position measurement result of the point to be measured.

12. The measuring method according to claim 11, characterized in that: The first position measurement results at the multiple moments are weightedly fused based on a set first weight value.

13. The measuring method according to claim 11, characterized in that: The following steps are also included: A second weight of the fused first position measurement result and the second position measurement result is set according to the image quality of the captured image corresponding to the second position measurement result.

14. A measurement system, characterized in that: For implementing the measurement method according to any one of claims 1 to 13, the system comprises: Laser ranging module, image measurement module and navigation module; A control module is used to obtain measurement data of the point to be measured, wherein the measurement data includes first measurement data obtained from the laser ranging module and second measurement data obtained from the image measurement module. The method comprises the steps of: calculating the position measurement result of the point to be measured based on the measurement data of the point to be measured and the third measurement data obtained from the navigation module; calculating at least one position measurement result of the point to be measured based on the measurement data of the point to be measured; and using a preset measurement fusion algorithm to calculate a final position measurement result of the point to be measured based on the at least one position measurement result.

15. A measuring device, characterized in that: include: case; A laser ranging module is arranged on the housing; An image measurement module is disposed on the housing, and a shooting direction of the image measurement module is consistent with a laser emission direction of the laser ranging module; A navigation module is at least partially disposed in the housing, and an antenna of the navigation module is disposed outside the housing; A control module is disposed inside the housing and is configured to execute the steps in the measurement method according to any one of claims 1 to 13.

16. A computer-readable storage medium for storing a program, characterized in that: When the program is executed by a processor, the steps of the measurement method according to any one of claims 1 to 13 are implemented.

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