A dynamic calibration and compensation method and system for laser positioning systems

Abstract

This invention belongs to the field of precision measurement technology and relates to a dynamic calibration and compensation method and system for laser positioning systems. The method includes: 1) adding an inertial measurement unit (IMU) to an optical signal receiver to obtain the velocity and pose information of the optical signal receiver; 2) calculating the dynamic error of the scanning angle introduced by the relative motion between the optical signal receiver and the measurement base station based on the velocity information; 3) compensating the dynamic error of the scanning angle to the scanning angle output value of the optical signal receiver to obtain the compensated scanning angle and obtaining the pose information of the optical signal receiver during two measurements based on it; 4) interpolating the pose information obtained in step 1) between the pose information during the two measurements to obtain more pose information of the optical receiver in the same amount of time. This can significantly shorten the calibration time in the early stage of establishing the measurement field.

Description

Technical Field

[0001] This invention relates to the field of precision measurement technology for large indoor spaces, specifically a dynamic calibration and motion error compensation method based on a laser positioning system, which is suitable for high-precision and rapid measurement tasks in the manufacturing and assembly process of large workpieces. Background Technology

[0002] With the improvement of modern industrial manufacturing levels, high-precision measurement technology for large-size components has become a key bottleneck restricting the intelligent development of equipment manufacturing assembly lines in intelligent manufacturing processes, facing the need for breakthroughs and updates in several key technologies. Accurate Large-scale Positioning System (ALPS), as a new type of indoor space laser positioning system, possesses advantages such as rapid, parallel measurement and sub-millimeter positioning accuracy, providing a novel solution for the automated manufacturing and flexible assembly of large equipment. Based on these characteristics, highly automated and high-precision large-size measurement and positioning systems have become an effective solution for ensuring the quality and efficiency of large-size workpiece manufacturing and assembly, and are widely used in the digital manufacturing, assembly, and maintenance of large equipment in aerospace, aviation, and shipbuilding industries.

[0003] Currently, the ALPS system has undergone several generations of upgrades. Although its static measurement accuracy can reach ±0.2mm, it requires a significant amount of time and manpower to calibrate the entire measurement field space during its establishment. Most current applications use static calibration methods, such as manually changing the pose of a high-precision standard ruler or target plate multiple times within the measurement space. Typically, achieving a positioning accuracy of 0.2mm / m in a 15m×15m×5m measurement space using a standard ruler-based static calibration method takes 3-4 hours. As the measurement area increases, the time cost of measurement field calibration increases exponentially. The significant time spent establishing the measurement field fails to meet the requirement of rapidly establishing a measurement field for measurement tasks.

[0004] Given the aforementioned technical deficiencies of existing technologies, there is an urgent need to develop a dynamic calibration and accuracy compensation method that can be effectively used in all-space laser positioning systems to solve the problems of long deployment cycles and poor adaptability to dynamic scenarios caused by low calibration efficiency in existing technologies. Summary of the Invention

[0005] This invention aims to overcome the shortcomings of the prior art and provide a dynamic calibration and compensation method and system for laser positioning systems. It is a dynamic calibration and error compensation method for laser positioning systems that integrates inertial units, which can significantly shorten the calibration time in the early stage of establishing the measurement field.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A dynamic calibration and compensation method for a laser positioning system, characterized by comprising the following steps:

[0008] 1) An inertial measurement unit is added to the optical signal receiver of the laser positioning system, and the velocity and pose information of the optical signal receiver are obtained through the inertial measurement unit;

[0009] 2) Based on the speed information, the dynamic error of the scanning angle introduced by the relative motion between the optical signal receiver and the measurement base station is calculated;

[0010] 3) The scanning angle dynamic error is compensated to the scanning angle output value of the optical signal receiver to obtain the compensated scanning angle and the pose information of the optical signal receiver during the two measurements is obtained based on the compensated scanning angle;

[0011] 4) Interpolate the pose information of the optical signal receiver calculated in step 1) between the pose information of the optical signal receiver during the two measurements, so as to obtain more pose information of the optical receiver in the same time.

[0012] Preferably, in step 1), the attitude information of the optical signal receiver is represented by a quaternion.

[0013] Preferably, in step 2), the dynamic error Δθ of the scanning angle introduced by the relative motion between the optical signal receiver and the measurement base station is expressed as: Δθ=Δθ h +Δθ v , where Δθ h The scanning angle error introduced by horizontal motion, Δθ v The scanning angle error introduced by vertical movement.

[0014] Preferably, in step 2), the Δθ is obtained by the following method. h :

[0015] The velocity information is decomposed to obtain the horizontal velocity;

[0016] The instantaneous radius of rotation in the horizontal direction is calculated based on the horizontal velocity.

[0017] The horizontal tangential receiver displacement is calculated based on the instantaneous rotation radius in the horizontal direction;

[0018] The scanning angle error Δθ introduced by the horizontal motion is calculated based on the displacement of the horizontal tangential receiver. h .

[0019] Preferably, in step 2), the Δθ is obtained by the following method. v :

[0020] The velocity information is decomposed to obtain the vertical velocity;

[0021] The instantaneous rotation radius in the vertical direction is calculated based on the vertical velocity.

[0022] The angle between the sector and the axis of rotation is calculated based on the instantaneous rotation radius in the vertical direction.

[0023] The scanning angle error Δθ introduced by the vertical motion is calculated based on the angle between the fan-shaped surface and the rotation axis. v .

[0024] Preferably, in step 4), a piecewise cubic spline interpolation method is used when performing interpolation.

[0025] Preferably, in step 4), the piecewise cubic spline interpolation method is used for interpolation as follows:

[0026] 41) Calculate the interval length and boundary conditions;

[0027] 42) Construct a system of equations and calculate the coefficients of each term;

[0028] 43) Solve for the auxiliary variables and polynomial coefficients;

[0029] 44) Perform interpolation calculations to obtain the interpolation value corresponding to any time.

[0030] Furthermore, the present invention also provides a dynamic calibration and compensation system for a laser positioning system, characterized in that it comprises:

[0031] The information acquisition module is used to add the inertial measurement unit to the optical signal receiver of the laser positioning system, and obtain the velocity and pose information of the optical signal receiver through the inertial measurement unit;

[0032] A scanning angle dynamic error calculation module is used to calculate the scanning angle dynamic error caused by the relative motion between the optical signal receiver and the measurement base station based on the velocity information.

[0033] The pose information measurement module is used to compensate the dynamic error of the scanning angle to the scanning angle output value of the optical signal receiver, so as to obtain the compensated scanning angle and obtain the pose information of the optical signal receiver during the two measurements based on the compensated scanning angle.

[0034] An interpolation module is used to interpolate the pose information of the optical signal receiver calculated in the information acquisition module to the pose information of the optical signal receiver during two measurements, so as to obtain more pose information of the optical receiver in the same amount of time.

[0035] Furthermore, the present invention also provides a dynamic calibration and compensation device for a laser positioning system, characterized in that it comprises:

[0036] One or more processors;

[0037] Memory, used to store one or more programs;

[0038] When the one or more programs are executed by the one or more processors, the one or more processors implement the dynamic calibration and compensation method for the laser positioning system as described above.

[0039] Finally, the present invention also provides a computer-readable storage medium having a computer program stored thereon, characterized in that, when the program is executed by a processor, it implements the steps of the dynamic calibration and compensation method for a laser positioning system as described above.

[0040] Compared with the prior art, the dynamic calibration and compensation method and system for laser positioning systems of the present invention have one or more of the following beneficial technical effects:

[0041] 1. This invention can perform dynamic calibration for indoor measurement fields and can verify dynamic scanning errors using parameters within the measurement base station.

[0042] 2. This invention integrates an inertial unit for dynamic calibration and error compensation of the laser positioning system, which can significantly shorten the calibration time in the early stage of establishing the measurement field. Attached Figure Description

[0043] Figure 1 This is a flowchart of the dynamic calibration and compensation method for a laser positioning system according to the present invention.

[0044] Figure 2 This is a schematic diagram illustrating the dynamic calibration error formation mechanism of a laser positioning system.

[0045] Figure 3 This is a schematic diagram of the dynamic calibration and compensation system for laser positioning systems according to the present invention. Detailed Implementation

[0046] Before detailing any embodiment of the invention, it should be understood that the invention, in its application, is not limited to the details of the construction and arrangement of the components set forth in the following description or illustrated in the following figures. The invention can have other embodiments and can be practiced or carried out in various ways. Furthermore, it should be understood that the wording and terminology used herein are for descriptive purposes and should not be considered limiting. The use of “comprising” or “having” and variations thereof is intended to cover the items set forth below and their equivalents, as well as any additional items. Unless otherwise specified or limited, the terms “installation,” “connection,” “support,” and “linkage,” and variations thereof are used broadly and cover both direct and indirect installation, connection, support, and linking. Moreover, “connection” and “linkage” are not limited to physical or mechanical connections or links.

[0047] Furthermore, firstly, in the disclosure of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limiting this invention. Secondly, the term "a" should be understood as "at least one" or "one or more," that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. The term "a" should not be construed as a limitation on the quantity.

[0048] To address the problems existing in the prior art, this invention combines the existing calibration methods of laser positioning systems to provide a dynamic calibration method for indoor measurement fields and uses the parameters within the measurement base station to verify the dynamic scanning error. Furthermore, it designs a dynamic calibration and error compensation method for laser positioning systems that integrates inertial units, which can significantly shorten the calibration time during the initial establishment of the measurement field.

[0049] Figure 1 A flowchart of the dynamic calibration and compensation method for a laser positioning system according to the present invention is shown. Figure 1 As shown, the dynamic calibration and compensation method for a laser positioning system of the present invention includes the following steps:

[0050] I. Information Acquisition

[0051] An inertial measurement unit is added to the optical signal receiver of the laser positioning system, and the velocity and pose information of the optical signal receiver are obtained through the inertial measurement unit.

[0052] In this invention, the optical signal receiver of the laser positioning system is fixedly connected to the inertial measurement unit (IMU), so that the velocity and pose information output by the IMU can be considered as the velocity and pose information of the optical signal receiver. The IMU velocity information is measured using an accelerometer; that is, the accelerometer measures the relative force, projects it onto the navigation coordinate system through an attitude transformation matrix, subtracts gravitational acceleration and Coriolis acceleration to obtain the IMU's acceleration, performs one integration to obtain the IMU's velocity, and performs another integration to obtain the IMU's position. The IMU's pose information is measured using the Earth's rotation and a gyroscope to obtain the projection of the angular velocity of the IMU coordinate system relative to the navigation coordinate system in the IMU coordinate system, and integrates this projection to obtain the pose information.

[0053] In this invention, quaternions are used to represent the pose information obtained by the inertial measurement unit, thus avoiding the degradation of Euler angles and the large computational burden of the direction cosine matrix.

[0054] Specifically, assume that the moving coordinate system b has an angular velocity ω relative to the reference coordinate system R. Rb Rotation, then quaternion Let Δθ be the equivalent rotation vector of the moving coordinate system b from its pose at time t to its position at time t+Δt, which is a function of time. According to the definition of the derivative:

[0055]

[0056] Assuming the direction of the angular velocity vector remains constant during the update period (fixed-axis rotation), using the Picard approximation method, a closed-form solution to the quaternion differential equation can be obtained. The particular solution of this differential equation is:

[0057]

[0058] Choosing the inertial frame as the reference coordinate system, the pose update algorithm is as follows:

[0059]

[0060] The above equation holds true only if the moving coordinate system b is in [t]. k-1 t k It can rotate around a fixed axis within a certain time, but this is difficult to achieve in practical applications. Therefore, an equivalent angular velocity with "unchanged direction" can be constructed based on the angular velocity measurement value and then substituted into the pose update equation.

[0061] Assume the moving coordinate system b starts from an initial orientation (t) aligned with the R system, revolving around the positive direction of vector φ. k-1 After rotating by an angle ||φ|| at time (t), the current moving coordinate system b(t) is obtained. k (Time), let t = t k ,have:

[0062]

[0063] A single angular increment output from a gyroscope cannot yield the corresponding equivalent rotation vector. Therefore, a mathematical model is needed to approximate the true angular motion of the IMU by making certain assumptions about several gyroscope angular increment outputs over a time interval. A bisample assumption model is adopted, where the angular velocity vector is calculated over the integral time [t]. k-2 ,t k The value of the equivalent rotating vector changes linearly with time, so the solution for the bisample is:

[0064]

[0065] Given the pose at the previous moment and the angular increment Δθ of the gyroscope output k , Δθ k-1 Then the pose at the current moment This can be achieved using quaternion multiplication:

[0066]

[0067] Finally, the updated pose quaternion is normalized.

[0068] Given that the specific force measurement from the accelerometer lies in a specific coordinate system (i.e., the specific force measurement is projected onto this coordinate system), and the orientation of this coordinate system relative to the inertial coordinate system is determined by a gyroscope, we can solve Newton's equations of motion. For navigation applications on the Earth's surface, we have:

[0069]

[0070] Velocity update involves solving the corresponding ground velocity differential equation in the selected coordinate system, projecting the velocity differential equation onto the navigation coordinate system, and then integrating and discretizing it to obtain:

[0071]

[0072] In the above equation, all variables within the integral sign are functions of time. Since the integrand is difficult to simplify further, a bisample hypothesis is made: during the integration time interval [t]... k-2 ,t k Within this range, both the angular velocity and specific force observations change linearly with time. Substituting this assumption into the velocity update equation and simplifying, we obtain:

[0073]

[0074] This completes the update of motion information (including velocity and pose information) in the IMU.

[0075] II. Calculation of dynamic error of scanning angle.

[0076] The dynamic error of the scanning angle introduced by the relative motion between the optical signal receiver and the measurement base station is calculated based on the speed information.

[0077] When the optical signal receiver of the laser positioning system moves relative to the measurement base station, the spatial position of the optical signal receiver changes when the reference light from a single measurement base station and the two sector laser beams arrive at the optical signal receiver. This causes the different laser sectors to fail to converge at the same spatial position of the optical signal receiver. As a result, the scanning angle of the two sector laser beams changes relative to the optical signal receiver when it is stationary, thus generating a sector scanning angle phase error.

[0078] The following example, using two measuring base stations and a standard ruler with optical signal receivers at both ends, illustrates the formation process of dynamic measurement errors introduced by the relative motion of the measuring base stations and optical signal receivers. The arrival times of the reference light at measuring base stations 1 and 2 are recorded as t. 10 and t 20 The time point used as the timer for the measurement cycle, i.e., the time when the sector lasers 1 and 2 of the two measurement base stations sweep across the optical signal receiver, is t. 111 ,t 112 t 211 ,t 212 t 121 ,t 122 t 221 ,t 222 Among them, t 121 This indicates the moment when the second fan-shaped laser beam from the first measuring base station sweeps across the optical signal receiver 1 on the standard ruler, as shown in the attached figure. Figure 2 As shown.

[0079] During static measurement, t 10 ~t 222 The spatial position of the optical signal receiver remains unchanged within a given time period, and the scanning angles of each sector laser converge at the position of the optical signal receiver, satisfying the intersection condition. During the dynamic measurement process, the standard ruler moves along the trajectory shown in the figure, at time t... 10 ~t 222 At different times within the time frame, the spatial position and pose of the optical signal receiver are different. If the measured timestamp is used directly to calculate the pose of the optical signal receiver, scanning angle error will be introduced, causing the calculated pose to be inconsistent with the actual pose.

[0080] Therefore, in this invention, it is necessary to calculate the scanning angle dynamic error introduced by the relative motion between the optical signal receiver and the measurement base station based on the speed information, and use the scanning angle dynamic error to compensate for the scanning angle output value of the optical signal receiver.

[0081] In this invention, a kinematic model of scanning angle error is established using a single sector of a single measurement base station. The velocity information of the optical signal receiver is decomposed along the horizontal and vertical directions of the base station coordinate system, and models are created for each of the two directions. Finally, the errors of the two sub-models are superimposed to obtain the relationship between the overall motion error of the optical signal receiver and the scanning angle.

[0082] Specifically, let the normal vector of the laser sector LP1 be n = [abc]. T With a Y-intercept of d, the coordinates of the optical signal receiver in the base station coordinate system are (x... p y p z p ), the velocity of motion is (v x v y v z If the horizontal and vertical velocities are decomposed as follows:

[0083]

[0084] Considering the horizontal direction, let the equation of the laser plane be ax + bz + cy + d = 0, and the equation of the line l be ax p +bz p +(cy p +d)=0, in Y=y p In the plane, passing through O p Draw a perpendicular line to l, intersecting l at point O. p ′, then at this time O p ′ can be considered as the center of rotation of point P, O P ′P is the instantaneous radius of rotation, which can be obtained from geometric relations:

[0085]

[0086] At time t0, the reference light arrives at point P, and at time t1, the sector laser LP1 arrives at point P1. Then, the displacement of the optical signal receiver is:

[0087] PP1 = v h (t1-t0).

[0088] Decompose the horizontal velocity of the optical signal receiver at point P along the intersection line l and in the direction perpendicular to l to obtain the tangential velocity v. t and radial velocity v r :

[0089]

[0090] Due to the radial velocity v in the air r Since the speed of light is much smaller than the speed of light c, the effect of radial motion on the scanning angle error can be ignored. During the time interval from t0 to t1, the optical signal receiver is at a tangential velocity vt Under the action of the action, the tangential displacement is:

[0091] s = v t (t1-t0).

[0092] The measurement error of the scanning angle introduced by the horizontal movement is:

[0093]

[0094] Considering the vertical direction, at time t0, the optical signal receiver is at point P(x). p y p z p The reference optical signal is received, and the speed of the optical signal receiver is (0 0 v). y At time t1, the fan-shaped laser LP1 sweeps across the optical signal receiver located at point P1, using the plane Y = y p The scanning light plane at time t0 intersects LP1 at a straight line l, passing through O. p Draw a perpendicular line from l to intersect l at point O. p Similarly, the center of rotation O can be obtained. p ′ and rotation radius O p P. Using the plane Y = y p The light plane at time t1 intersects LP1 at line k. PQ ​​is drawn perpendicular to line k through point P. From geometric relations, we obtain ∠PO p Q' is the scanning angle error caused by the vertical movement of the optical signal receiver from time t0 to t1.

[0095]

[0096] If the optical signal receiver moves only vertically from time t0 to t1, then PP1 = v y (t1-t0) is perpendicular to the plane Y = y p LP1 rotates around the Y-axis, therefore, during the rotation, the angle between LP1 and the Y-axis... constant, The angle can be obtained from the base station's internal parameters:

[0097]

[0098] And because The vertical scanning angle error is:

[0099]

[0100] In summary, the scanning angle error Δθ introduced by the relative motion between the optical signal receiver and the measurement base station can be expressed as:

[0101]

[0102] III. Position and pose information measurement.

[0103] After obtaining the scanning angle dynamic error, the scanning angle dynamic error is compensated to the scanning angle output value of the optical signal receiver to obtain the compensated scanning angle. Then, the pose information of the optical signal receiver during the two measurements can be obtained based on the compensated scanning angle.

[0104] IV. Interpolation.

[0105] The pose information of the optical signal receiver calculated in step one is interpolated between the pose information of the optical signal receiver during the two measurements, so as to obtain more pose information of the optical receiver in the same amount of time.

[0106] In this invention, the pose information output by the IMU is interpolated into the adjacent interval between two measurement cycles of the laser positioning system. While the IMU has a high data output frequency, it suffers from cumulative errors. The laser positioning system has a lower data output frequency but is more accurate, especially in terms of long-term stability. The purpose of interpolation is to use IMU data to fill or smooth the pose estimation between measurement points of the laser positioning system, where the IMU provides short-term high-frequency data, and the ALPS provides long-term correction.

[0107] As an inertial sensing device, an IMU (Inertial Measurement Unit) only needs initial pose information to calculate the instantaneous attitude, velocity, and position of a carrier, and it exhibits strong anti-interference capabilities. The IMU's measurement accuracy is excellent within a short timeframe, providing high-frequency data refresh for laser positioning systems. By inserting the carrier's velocity and position calculated by the IMU between two measurements in the laser positioning system, the frequency of measurement data output from the fusion system can be increased.

[0108] In this invention, a piecewise cubic spline interpolation method is employed based on the data characteristics of the laser positioning system and the IMU. This method ensures the continuity of function values, first derivatives (velocity), and second derivatives (acceleration) at the endpoints (measurement points of the laser positioning system), thereby providing a smooth motion trajectory, reducing Runge phenomenon or unreasonable oscillations, and is suitable for time-series data. It can utilize the high-frequency sampling points of the IMU to improve interpolation accuracy. By using the measurement points of the laser radar system as constraints, spline interpolation can effectively suppress the cumulative drift of the IMU. That is, at the two endpoints of the interpolation interval, the interpolation curve is forced to pass through the measurement values ​​of the laser positioning system, fitting a cubic spline curve and outputting the pose estimate of the optical signal receiver at any given time.

[0109] Specifically, at time points t0 to t n The measurement values ​​corresponding to that time point (the pose information obtained by the optical signal receiver during measurement) f0~f nThen, the length h of the interpolation interval is calculated. i =t i+1 -t i (i = 0, 1, ..., n-1), in each interval [t i ,t i+1 Construct a cubic polynomial on the above:

[0110] S i (t)=a i +b i (tt i )+c i (tt i ) 2 +d i (tt i ) 3 .

[0111] There are 4n coefficients a to be determined i b i c i d i Consider introducing the second derivative at the node as an auxiliary variable. Let's establish the equation. Where the left endpoint S... i (t i ) = a i =y i The right endpoint S i (t i+1 ) = a i +b i h i +c i h i 2 +d i h i 3 =y i+1 Since the first derivative is continuous, we have and Substituting, we get:

[0112] b i =b i-1 +2c i-1 h i-1 +3d i-1 h 2 i-1 .

[0113] Similarly, since the second derivative is continuous, we can obtain:

[0114] 2c i =2c i-1 +6d i-1 h i-1 .

[0115] And the boundary conditions are:

[0116] By the definition of the second derivative, let at the nodes... Substituting the interpolation conditions and simplifying, we get:

[0117] Since the first derivative is continuous, we can obtain:

[0118]

[0119] Sorting to μ i M i-1 +2M i +λ i M i+1 =g i ,in Written in matrix form:

[0120]

[0121] This invention interpolates the high-frequency output information of the IMU into two measurement cycles of the laser positioning system and aligns the two types of data on the time axis. This allows for the acquisition of more pose information from the optical signal receiver within the same timeframe, increasing the measurement frequency of the fusion system and reducing the calibration time of the measurement field. Furthermore, the instantaneous scanning angle dynamic error of the base station sector is compensated to the original scanning angle output value of the laser positioning system on the solution frame, eliminating phase errors caused by the operation of the optical signal receiver.

[0122] Figure 3 A schematic diagram of the dynamic calibration and compensation system for a laser positioning system according to the present invention is shown. Figure 3 As shown, the dynamic calibration and compensation system for a laser positioning system of the present invention includes:

[0123] 1. Information Acquisition Module.

[0124] The information acquisition module is used to add the inertial measurement unit to the optical signal receiver of the laser positioning system, and obtain the velocity and pose information of the optical signal receiver through the inertial measurement unit.

[0125] 2. Scan Angle Dynamic Error Calculation Module.

[0126] The scanning angle dynamic error calculation module is used to calculate the scanning angle dynamic error caused by the relative motion between the optical signal receiver and the measurement base station based on the speed information.

[0127] 3. Pose information measurement module.

[0128] The pose information measurement module is used to compensate the dynamic error of the scanning angle to the scanning angle output value of the optical signal receiver, so as to obtain the compensated scanning angle and obtain the pose information of the optical signal receiver during the two measurements based on the compensated scanning angle.

[0129] 4. Interpolation module.

[0130] The interpolation module is used to interpolate the pose information of the optical signal receiver calculated in the information acquisition module to the pose information of the optical signal receiver during two measurements, so as to obtain more pose information of the optical receiver in the same time.

[0131] Furthermore, the present invention also provides a dynamic calibration and compensation device for a laser positioning system, comprising: one or more processors; a memory for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the dynamic calibration and compensation method for a laser positioning system as described above.

[0132] Finally, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the dynamic calibration and compensation method for a laser positioning system as described above.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Those skilled in the art can modify or make equivalent substitutions to the technical solutions of the present invention based on the concept of the present invention, without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A dynamic calibration and compensation method for a laser positioning system, characterized in that, Includes the following steps: 1) An inertial measurement unit is added to the optical signal receiver of the laser positioning system, and the velocity and pose information of the optical signal receiver are obtained through the inertial measurement unit; 2) Based on the speed information, the dynamic error of the scanning angle introduced by the relative motion between the optical signal receiver and the measurement base station is calculated; 3) The scanning angle dynamic error is compensated to the scanning angle output value of the optical signal receiver to obtain the compensated scanning angle and the pose information of the optical signal receiver during the two measurements is obtained based on the compensated scanning angle; 4) Interpolate the pose information of the optical signal receiver calculated in step 1) between the pose information of the optical signal receiver during the two measurements, so as to obtain more pose information of the optical receiver in the same time.

2. The dynamic calibration and compensation method for a laser positioning system according to claim 1, characterized in that, In step 1), quaternions are used to represent the attitude information of the optical signal receiver.

3. The dynamic calibration and compensation method for a laser positioning system according to claim 1, characterized in that, In step 2), the dynamic error Δθ of the scanning angle introduced by the relative motion between the optical signal receiver and the measurement base station is expressed as: Δθ=Δθ h +Δθ v , where Δθ h The scanning angle error introduced by horizontal motion, Δθ v The scanning angle error introduced by vertical movement.

4. The dynamic calibration and compensation method for a laser positioning system according to claim 3, characterized in that, In step 2), the Δθ is obtained by the following method. h : The velocity information is decomposed to obtain the horizontal velocity; The instantaneous radius of rotation in the horizontal direction is calculated based on the horizontal velocity. The horizontal tangential receiver displacement is calculated based on the instantaneous rotation radius in the horizontal direction; The scanning angle error Δθ introduced by the horizontal motion is calculated based on the displacement of the horizontal tangential receiver. h .

5. The dynamic calibration and compensation method for a laser positioning system according to claim 3, characterized in that, In step 2), the Δθ is obtained by the following method. v : The velocity information is decomposed to obtain the vertical velocity; The instantaneous rotation radius in the vertical direction is calculated based on the vertical velocity. The angle between the sector and the axis of rotation is calculated based on the instantaneous rotation radius in the vertical direction. The scanning angle error Δθ introduced by the vertical motion is calculated based on the angle between the fan-shaped surface and the rotation axis. v .

6. The dynamic calibration and compensation method for a laser positioning system according to claim 1, characterized in that, In step 4), the piecewise cubic spline interpolation method is used when performing interpolation.

7. The dynamic calibration and compensation method for a laser positioning system according to claim 6, characterized in that, In step 4), the piecewise cubic spline interpolation method is used for interpolation as follows: 41) Calculate the interval length and boundary conditions; 42) Construct a system of equations and calculate the coefficients of each term; 43) Solve for the auxiliary variables and polynomial coefficients; 44) Perform interpolation calculations to obtain the interpolation value corresponding to any time.

8. A dynamic calibration and compensation system for a laser positioning system, characterized in that, include: The information acquisition module is used to add the inertial measurement unit to the optical signal receiver of the laser positioning system, and obtain the velocity and pose information of the optical signal receiver through the inertial measurement unit; A scanning angle dynamic error calculation module is used to calculate the scanning angle dynamic error caused by the relative motion between the optical signal receiver and the measurement base station based on the velocity information. The pose information measurement module is used to compensate the dynamic error of the scanning angle to the scanning angle output value of the optical signal receiver, so as to obtain the compensated scanning angle and obtain the pose information of the optical signal receiver during the two measurements based on the compensated scanning angle. An interpolation module is used to interpolate the pose information of the optical signal receiver calculated in the information acquisition module to the pose information of the optical signal receiver during two measurements, so as to obtain more pose information of the optical receiver in the same amount of time.

9. A dynamic calibration and compensation device for a laser positioning system, characterized in that, include: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the dynamic calibration and compensation method for a laser positioning system as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the dynamic calibration and compensation method for a laser positioning system as described in any one of claims 1-7.

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