Positioning method for control center of six-degree-of-freedom motion platform

Abstract

The application discloses a positioning method of a six-degree-of-freedom motion platform control center, and through correction of two errors of a position error of a sensor-bound control center and a real control center and a six-degree-of-freedom motion platform world coordinate system and a laser tracker world coordinate system error, the accuracy of finding a world coordinate system and an actual control center can be improved, a measurement model is constructed in combination with a laser tracker and T-MAC and other hardware devices, and calibration of the six-degree-of-freedom motion platform can be well completed. After measurement errors are corrected and eliminated, real-time platform control values are provided in a motion state of the platform, measurement values are acquired in real time through a relatively fixed T-MAC hardware device, and real-time dynamic calibration can be completed through comparison between the two. The method has high accuracy and efficiency, and can be widely applied to the six-degree-of-freedom motion platform.

Description

[Technical Field]

[0001] This invention relates to the technical field of six-degree-of-freedom motion platforms, and in particular to the technical field of positioning methods for the control center of a six-degree-of-freedom motion platform. [Background Technology]

[0002] The motion control accuracy of a six-degree-of-freedom (DOF) motion platform directly affects the simulation effect of its built environment, impacting everything from large-scale scientific research experiments, engineering construction, and technological development to the immersive effects of virtual reality. Therefore, there is an urgent need to research scientific and effective methods to measure and calibrate the characteristic parameters of a six-DOF motion platform to verify whether the actual simulation environment meets the target requirements for production and development. Currently, most measurement and calibration methods for six-DOF motion platforms are technical specifications that perform partial tests on single postures or displacements. However, there is still no complete and systematic method for calibrating composite motions, especially the dynamic characteristics of composite motions.

[0003] Existing measurement methods for six-degree-of-freedom (6DOF) motion platforms generally start from independent measurements of displacement along a single coordinate axis or rotation in a single direction (hereinafter referred to as "single degree of freedom"). This does not actually reflect the reality of a six-DOF motion platform. Measuring the composite motion of the platform's six degrees of freedom is the more logical approach. Single-degree-of-freedom independent measurements only demonstrate the accuracy of the six-DOF motion platform in single-axis displacement or rotation. This means that when the platform is performing single-degree-of-freedom motion, accurate measurement results can be obtained regardless of the target's position on the platform. However, a six-DOF motion platform is actually performing composite motion of six degrees of freedom. In this motion mode, because the motion commands sent by the six-DOF platform are only directed to the control center, only the position and attitude description P of the control center of the six-DOF motion platform is relevant. 6d控制中心 Only the coordinates (x, y, z, rx, ry, rz) can represent the motion position and attitude information of a six-degree-of-freedom platform; other measurement points on the platform cannot represent it. Therefore, the original method of independent measurement of a single degree of freedom obviously cannot accurately reflect the platform performance of a six-degree-of-freedom motion platform under complex motion; it is a local and one-sided measurement method. Thus, the key to accurately measuring the position and attitude of a six-degree-of-freedom motion platform lies in finding its control center.

[0004] In practical applications, the control center of a six-degree-of-freedom (6DOF) motion platform can be roughly determined using traditional methods. Generally, a 6DOF motion platform itself does not provide a reference for its world coordinate system; therefore, it is necessary to measure various motion states of the platform to find its world coordinate system and actual control center. Traditional methods involve resetting the 6DOF motion platform to its zero position, fixing a target at any non-control center location, controlling the platform to move along the Z-axis to determine the Z-axis direction, moving along the X-axis to determine the X-axis direction, and finally controlling the platform to rotate around the control center to determine its position. This allows us to determine the world coordinate system and control center position of the 6DOF motion platform. The coordinate system position of the control center of the 6DOF motion platform in its initial position is the world coordinate system position during testing.

[0005] However, traditional methods for locating the control center of a six-degree-of-freedom (6DOF) motion platform introduce several significant errors in practical operation. The repeatability of the world coordinate system established by traditional methods is highly dependent on the accuracy of the 6DOF motion platform itself. Since 6DOF motion platforms are often used in large-scale engineering projects and typically employ hydraulic control, their inherent control accuracy is not very high. Furthermore, due to the design and structural factors of the 6DOF motion platform, the rotation angles in some degrees of freedom are small (e.g., the rotation range around the Z-axis of a conventional 6DOF motion platform is very small, and finding the center of a circle with small rotation angles results in a large error), which also significantly affects the positioning accuracy of its control center. Therefore, while this traditional method theoretically has the possibility of finding the world coordinate system and control center of the 6DOF motion platform, it introduces several significant errors in practical operation. For example, controlling the 6DOF motion platform to rotate around a certain axis can generate coordinate values ​​for the other two axes of the control center. Rotating around all three axes will generate six coordinate values, three of which are repetitive. Often, due to the low accuracy of the measured equipment, the deviation between these repetitive coordinate values ​​is large. Alternatively, the non-perpendicularity of the three axes when controlling the six-degree-of-freedom motion platform to move along the X, Y, and Z axes can also cause errors in the constructed coordinate system. Ultimately, these errors manifest in two ways: the positional error between the sensor-attached control center and the actual control center, and the error between the world coordinate system of the six-degree-of-freedom motion platform and the world coordinate system of the laser tracker. Therefore, this traditional method can only serve as a coarse way to locate the six-degree-of-freedom world coordinate system and the control center. The inability of the traditional method to precisely locate the control center of the six-degree-of-freedom motion platform prevents manufacturers from adjusting the control center to a more intuitive and accurate initial position on the platform, resulting in reduced actual control accuracy of the six-degree-of-freedom motion platform and failing to meet the designed accuracy requirements.

[0006] The main applications of six-degree-of-freedom motion platforms are currently in environmental simulation, steady-state environment construction, and large workpiece assembly. Considering these applications and the characteristics of the six-degree-of-freedom motion platform itself, it is very important to determine the world coordinate system measurement and actual control center of the six-degree-of-freedom motion platform. This is not only beneficial for platform calibration and improving the platform's motion accuracy, but also provides a guarantee for the platform's application in real-world scenarios and better application expansion space.

[0007] To better illustrate the technical solution, the following terms are explained:

[0008] 1. Six-degree-of-freedom motion - Six-degree-of-freedom motion is divided into three translational positional motions and three rotational attitude motions. Especially in attitude rotation, the rotation method and rotation sequence are not unique. All positional and attitude motions described in this paper first rotate around the X-axis, Y-axis, and Z-axis of the world coordinate system in the order of (Δrx, Δry, Δrz), and then undergo displacement of (dx, dy, dz).

[0009] 2. Six-DOF point – This is a measured coordinate system bound to a six-DOF motion platform, representing a position and orientation state of the platform. It represents the object's position starting from the origin, rotating sequentially through (Δrx, Δry, Δrz), and then undergoing displacement through (dx, dy, dz), ultimately reaching a pose that can be represented by P. 6d (x,y,z,rx,ry,rz) represents a point with six degrees of freedom;

[0010] 3. Control center six-degree-of-freedom point P 6d控制中心 (x,y,z,rx,ry,rz) – A measured coordinate system is bound to the six-degree-of-freedom motion platform. The origin of this bound coordinate system is the control center, P. 6d控制中心 The first three parameters (x, y, z, rx, ry, rz) are position coordinates, which actually describe the position of the control center, P. 6d控制中心 The last three parameters (rx, ry, rz) of (x, y, z, rx, ry, rz) reflect the attitude of the six-degree-of-freedom motion platform by describing the current attitude of the control center.

[0011] 4. Matrix formulas for six-degree-of-freedom motion and six-degree-of-freedom points—For ease of calculation, six-degree-of-freedom motion and six-degree-of-freedom points are represented in matrix form;

[0012] 5. Origin P 6d The matrix form of (0,0,0,0,0,0) – the matrix at the origin is the identity matrix.

[0013] 6. Six-degree-of-freedom translation matrix —

[0014] 7. Six-degree-of-freedom rotation matrix —

[0015] Rotation Δrz around the Z-axis

[0016]

[0017] Rotation Δry around the Y-axis

[0018]

[0019] Rotation Δrx around the X-axis

[0020] [Summary of the Invention]

[0021] The purpose of this invention is to solve the problems in the prior art and propose a positioning method for the control center of a six-degree-of-freedom motion platform, which can improve the accuracy of world coordinate system measurement and control center finding of the six-degree-of-freedom motion platform and realize dynamic calibration of the six-degree-of-freedom motion platform.

[0022] To achieve the above objectives, this invention proposes a positioning method for the control center of a six-degree-of-freedom motion platform, comprising the following steps:

[0023] S1. Use traditional methods to coarsely determine the initial position of the world coordinate system and control center of the six-degree-of-freedom motion platform;

[0024] S2. Use a laser tracker and a T-MAC probe to measure a large number of motion poses that are uniformly distributed within the stroke range of a six-degree-of-freedom motion platform;

[0025] S3. Based on the measurement model of the six-degree-of-freedom motion platform, using the motion pose in step S2 as parameters, the position deviation of the control center and the position deviation of the world coordinate system of the six-degree-of-freedom motion platform are obtained through best fitting.

[0026] S4. Using the two deviations obtained from the fitting in step S3, adjust the control center position of the six-degree-of-freedom motion platform and the world coordinate system position in the laser tracker measurement software, respectively.

[0027] S5. The position and attitude of the six-degree-of-freedom motion platform are directly measured using the T-MAC probe.

[0028] Preferably, in step S1, a coarse positioning of the control center and world coordinate system of the six-degree-of-freedom motion platform is performed using a traditional method: the pin hole at the center of the surface of the six-degree-of-freedom motion platform is used as the control center of the six-degree-of-freedom motion platform, the position of the control center when the six-degree-of-freedom motion platform is in the zero-point state is used as the origin of the measurement coordinate system, and the three coordinate axis directions of the six-degree-of-freedom motion platform are used as the directions of the three axes of the measurement coordinate system.

[0029] Preferably, in step S2: based on the coarse positioning in step S1, a set of motion control commands P for i points is sent to the six-degree-of-freedom motion platform. 6d平台i (x 平台i ,y 平台i ,z 平台i ,rx 平台i ,ry 平台i ,rz 平台i The tracker measured values ​​P at a set of i points, which correspond one-to-one. 6d跟踪仪i (x 跟踪仪i ,y 跟踪仪i ,z 跟踪仪i ,rx 跟踪仪i ,ry 跟踪仪i ,rz 跟踪仪i The measured values ​​are used as parameters for the best fit in step S3.

[0030] Preferably, in step S3, P 6d The matrix form of a six-degree-of-freedom point (x,y,z,rx,ry,rz):

[0031] 6Dmartix=Trans(x,y,z)×Rotz(rz)×Roty(ry)×Rotx(rx)×I (1)

[0032] Substituting the i-th set of parameters obtained in step S2 into formula (1), we obtain the following objective function formula (2).

[0033]

[0034] In the formula, 6Dmartix 六自由度平台控制值i and 6Dmartix 激光跟踪仪测量值i They are respectively P 6d平台i (x 平台i ,y 平台i ,z 平台i ,rx 平台i ,ry 平台i ,rz 平台i ) and P 6d跟踪仪i (x 跟踪仪i ,y 跟踪仪i ,z 跟踪仪i ,rx 跟踪仪i ,ry 跟踪仪i ,rz 跟踪仪i Substituting into formula (1) yields the matrix form;

[0035] Meanwhile, the matrix expansion terms of formula (1) are listed, where 6Dmartix[ij] is the i-th row and j-th column of the 6Dmartix matrix:

[0036]

[0037] Formula (3) can be used to derive formula (4).

[0038] rx=arctan(6Dmartix[3 2] / 6Dmartix[3 3])

[0039]

[0040] rz=arctan(6Dmartix

[21] / 6Dmartix

[11] )

[0041] x = 6Dmartix

[14]

[0042] y = 6Dmartix

[24]

[0043] z = 6Dmartix

[34] (4)

[0044] 6Dmartix 激光跟踪仪测量值i Substituting into formulas (2) and (4), we get B. i The function of X is shown in formula (5):

[0045]

[0046] Where X=[Δrz1Δry1Δrx1 dx1 dy1 dz1 dx2 dy2 dz2Δrz2Δry2Δrx2] T Therefore, when there are n measurement points, we can obtain formula (6) by solving the system of equations:

[0047]

[0048] Where Y = [Y1Y2…Y] n ] T The motion control position, Y, is obtained by sending n motion control commands to a six-degree-of-freedom motion platform. i =[x 平台i y 平台i z 平台i rz 平台i ry 平台i rx 平台i ] T F(X) is B i A system of simultaneous equations;

[0049] Let the zero matrix be X = [Δrz1Δry1Δrx1 dx1 dy1 dz1 dx2 dy2 dz2Δrz2Δry2Δrx2] T The initial value is obtained by iterating according to formula (9).

[0050] X k+1 =X k -(J T J) -1 [J T (F(X k (9)

[0051] Where J is Y = F(X) k The Jacobian matrix of ) is obtained by using the Newton's downhill method to iterate and minimize the sum of squares of the errors on both sides of equation (9), thus obtaining the best fitting values ​​of X, namely (dx1,dy1,dz1,Δrx1,Δry1,Δrz1) and (dx2,dy2,dz2,Δrx2,Δry2,Δrz2).

[0052] Preferably, in step S4, (dx1,dy1,dz1,Δrx1,Δry1,Δrz1) obtained in step S3 is used to adjust the pose of the world coordinate system in the tracking measurement software; (dx2,dy2,dz2,Δrx2,Δry2,Δrz2) is used to adjust the pose of the control center of the six-degree-of-freedom motion platform in the control software of the six-degree-of-freedom motion platform.

[0053] The beneficial effects of this invention are as follows: By correcting two major errors—the positional error between the sensor-bonded control center and the actual control center, and the error between the world coordinate system of the six-degree-of-freedom motion platform and the world coordinate system of the laser tracker—this invention improves the accuracy of finding the world coordinate system and the actual control center. Combined with hardware devices such as the laser tracker and T-MAC, a measurement model is constructed, enabling better calibration of the six-degree-of-freedom motion platform. After the measurement errors are corrected and eliminated, the platform provides real-time control values ​​during motion. These values ​​are acquired in real-time through the relatively fixed T-MAC hardware device, and the comparison between the two allows for real-time dynamic calibration. This method is highly accurate and efficient, and can be widely applied to six-degree-of-freedom motion platforms.

[0054] The features and advantages of the present invention will be described in detail through embodiments and in conjunction with the accompanying drawings. [Attached Image Description]

[0055] Figure 1 This is a measurement model diagram of the six-degree-of-freedom motion platform for the positioning method of the control center of the six-degree-of-freedom motion platform of the present invention.

Detailed Implementation Methods

[0056] This scheme proposes an optimal fitting method to determine the world coordinate system and actual control center of a six-degree-of-freedom motion platform. A laser tracker and T-MAC are used to measure a large number of motion poses uniformly distributed within the travel range of the six-degree-of-freedom motion platform. Based on the measurement model of the six-degree-of-freedom motion platform, the optimal fitting method is used to calculate the position of the control center and world coordinate system of the six-degree-of-freedom motion platform.

[0057] The measurement error model is analyzed as follows:

[0058] like Figure 1 As shown, this measurement model describes the correction model for two major errors introduced in traditional methods: the position error between the sensor-attached control center and the real control center, and the error between the world coordinate system of the six-degree-of-freedom motion platform and the world coordinate system of the laser tracker. The error between the world coordinate system of the six-degree-of-freedom motion platform and the world coordinate system of the laser tracker is compensated by six-degree-of-freedom motion (dx1,dy1,dz1,Δrx1,Δry1,Δrz1), and the position error between the sensor-attached control center and the real control center is compensated by six-degree-of-freedom motion (dx2,dy2,dz2,Δrx2,Δry2,Δrz2).

[0059] (dx1,dy1,dz1,Δrx1,Δry1,Δrz1) and (dx2,dy2,dz2,Δrx2,Δry2,Δrz2) can both be calculated using software based on this mathematical model and the actual measured data from the tracker.

[0060] The specific method is as follows:

[0061] The first step is to perform a coarse positioning of the control center and world coordinate system of the six-degree-of-freedom motion platform using the traditional method described above: the pin hole at the center of the surface of the six-degree-of-freedom motion platform is used as the origin of the tracker's world coordinate system, the Z+ axis of the six-degree-of-freedom motion platform is used as the main axis of the Z+ direction of the coordinate system, and the X+ direction of the six-degree-of-freedom motion platform is used as the secondary axis of the X+ direction of the world coordinate system. The Y+ direction is determined by the Z+ and X+ directions and the right-hand screw rule to establish the world coordinate system. When the six-degree-of-freedom motion platform is in the zero position, its control center coordinate system coincides with the world coordinate system. That is, in the zero position state, the T-MAC is used to bind the world coordinate system. When the pose of the six-degree-of-freedom platform changes, the T-MAC can continuously track the pose of its control center.

[0062] The second step is to send a set of motion control commands P to i points on the six-degree-of-freedom motion platform. 6d平台i (x 平台i ,y 平台i ,z 平台i ,rx 平台i ,ry 平台i ,rz平台i ), and the tracker measured values ​​P of a set of i points that correspond one-to-one. 6d跟踪仪i (x 跟踪仪i ,y 跟踪仪i ,z 跟踪仪i ,rx 跟踪仪i ,ry 跟踪仪i ,rz 跟踪仪i These measured values ​​will be used as parameters for the best fit in step S3;

[0063] Let X = [δ1δ2…δ 12 ] T =[Δrz1Δry1Δrx1 dx1 dy1 dz1 dx2 dy2 dz2Δrz2Δry2Δrx2] T The motion control command for the i-th point is Y. i =[x 平台i y 平台i z 平台i rz 平台i ry 平台i rx 平台i ] T The corresponding value measured by the tracker at the i-th point is: A i =[x 跟踪仪i y 跟踪仪i z 跟踪仪i rz 跟踪仪i ry 跟踪仪i rx 跟踪仪i ] T ;

[0064] Step 3, P 6d The matrix formula for a six-degree-of-freedom point (x, y, z, rx, ry, rz) is as follows:

[0065] 6Dmartix=Trans(x,y,z)×Rotz(rz)×Roty(ry)×Rotx(rx)×I (1)

[0066] Expanding formula (1) gives:

[0067]

[0068]

[0069] The formula for the measurement error model is as follows:

[0070]

[0071] A i Substituting into formula (8), we can obtain 6Dmartix 激光跟踪仪测量值iThen 6Dmartix 激光跟踪仪测量值i Substituting into formula (2), we can obtain 6Dmartix. 六自由度平台控制值i ;

[0072] Meanwhile, the matrix expansion terms of formula (1) are listed, where 6Dmartix[ij] is the i-th row and j-th column of the 6Dmartix matrix:

[0073]

[0074] Formula (3) can be used to derive formula (4).

[0075] rx=arctan(6Dmartix

[32] / 6Dmartix[3 3])

[0076]

[0077] rz=arctan(6Dmartix

[21] / 6Dmartix

[11] )

[0078] x = 6Dmartix

[14]

[0079] y = 6Dmartix

[24]

[0080] z = 6Dmartix

[34] (4)

[0081] The i-th group of laser tracker data A i =[x 跟踪仪i y 跟踪仪i z 跟踪仪i rz 跟踪仪i ry 跟踪仪i rx 跟踪仪i ] T By substituting into formulas (8), (2), and (4), we obtain B. i The function of X is shown in formula (5);

[0082] Then B i X can be represented as:

[0083]

[0084] Therefore, when there are n measurement points, we can obtain formula (6) by solving the system of equations:

[0085]

[0086] Where Y = [Y1Y2…Y] n ] TF(X) is the motion control position obtained from n motion control commands sent to a six-degree-of-freedom motion platform. F(X) is equivalent to B. i A system of simultaneous equations;

[0087] Next, we will use Newton's descent method to iteratively solve the problem:

[0088] Let the initial value be X0 = [000000000000] T ,

[0089] Iterate according to formula (9),

[0090] X k+1 =X k -(J T J) -1 [J T (F(X k (9)

[0091] Where J is Y = F(X) k The Jacobian matrix of is shown in formula (10).

[0092]

[0093] X k Let X be the value of X in the k-th iteration. k+1 Let X be the value of X in the (k+1)th iteration, where k = 0, 1, ...;

[0094] When (J) T J) -1 [J T (F(X k When [-Y)] < ε, the iteration stops, where ε is a manually set control threshold;

[0095] At this point, we can obtain X = [Δrz1Δry1Δrx1 dx1 dy1 dz1 dx2 dy2 dz2Δrz2Δry2Δrx2] T ,

[0096] The first six terms, Δrz1, Δry1, Δrx1, dx1, dy1, and dz1, are used for world coordinate system pose adjustment in the laser tracker measurement software, while the last six terms, dx2, dy2, dz2, Δrz2, Δry2, and Δrx2, are used for control center pose adjustment in the six-degree-of-freedom motion platform.

[0097] This technical solution improves the accuracy of finding the world coordinate system and the actual control center by correcting two major errors: the control center binding position error and the errors in the world coordinate system of the six-degree-of-freedom motion platform and the laser tracker. Combined with hardware such as the laser tracker and T-MAC, a measurement model is constructed, enabling effective calibration of the six-degree-of-freedom motion platform. After the measurement errors are corrected and eliminated, the platform provides real-time control values ​​during motion. These values ​​are acquired in real-time by the relatively fixed T-MAC hardware, and real-time dynamic calibration is achieved by comparing the two values. This method is highly accurate and efficient, and can be widely applied to six-degree-of-freedom motion platforms.

[0098] The measuring equipment used in the above technical solutions can be replaced by measuring equipment with similar functions. The laser tracker can be replaced by a large-size coordinate measuring machine, such as photogrammetry; the T-MAC can be replaced by other six-degree-of-freedom sensors or other measurement methods, such as constructing a coordinate system through three fixed targets.

[0099] The above embodiments are illustrative of the present invention and are not intended to limit the present invention. Any simple modifications to the present invention are within the scope of protection of the present invention.

Claims

1. A positioning method for the control center of a six-degree-of-freedom motion platform, characterized in that: Includes the following steps: S1. Use traditional methods to coarsely determine the initial position of the world coordinate system and control center of the six-degree-of-freedom motion platform; S2. Use a laser tracker and a T-MAC probe to measure a large number of motion poses that are uniformly distributed within the stroke range of a six-degree-of-freedom motion platform; S3. Based on the measurement model of the six-degree-of-freedom motion platform, using the motion pose in step S2 as parameters, the position deviation of the control center and the position deviation of the world coordinate system of the six-degree-of-freedom motion platform are obtained through best fitting. S4. Using the two deviations obtained from the fitting in step S3, adjust the control center position of the six-degree-of-freedom motion platform and the world coordinate system position in the laser tracker measurement software, respectively. S5. The position and attitude of the six-degree-of-freedom motion platform are directly measured using the T-MAC probe; In step S3 The matrix formula for six degrees of freedom: （1）； The result obtained in step S2 i Substituting the parameters into formula (1), we obtain the following objective function formula (2): （2）； In the formula, and They are respectively to and Substitute into formula (1) to calculate the matrix form of the world coordinate system position deviation and the control center position deviation; Meanwhile, the matrix expansion terms of formula (1) are listed, among which for The first of the matrix Line 1 List: （3）； Formula (4) is derived from formula (3): （4）； Will Substituting into formulas (2) and (4), we get about The function is shown in formula (5): （5）； in , The six parameters of the positional deviation of the world coordinate system Six parameters of deviation from the control center position The twelve-dimensional vector formed, when there is When there are 10 measurement points, the simultaneous equations yield formula (6): （6）； in, Y is a vector composed of the position and attitude corresponding to n motion control commands, and is the vector sent to the six-degree-of-freedom motion platform. The motion control position is obtained from the next motion control command. , Right now A system of simultaneous equations; Using the zero matrix as The initial value is obtained by iterating according to formula (9): （9）； in, for The Jacobian matrix is ​​obtained by using Newton's descent method to iterate and minimize the sum of squares of the errors on both sides of equation (9), thus obtaining... ,Right now and The best fit value.

2. The positioning method for the control center of a six-degree-of-freedom motion platform as described in claim 1, characterized in that: In step S1, a coarse positioning of the control center and world coordinate system of the six-degree-of-freedom motion platform is performed using traditional methods: the pin hole at the center of the surface of the six-degree-of-freedom motion platform is used as the control center of the six-degree-of-freedom motion platform, the position of the control center when the six-degree-of-freedom motion platform is in the zero-point state is used as the origin of the measurement coordinate system, and the three coordinate axis directions of the six-degree-of-freedom motion platform are used as the directions of the three axes of the measurement coordinate system.

3. The positioning method for the control center of a six-degree-of-freedom motion platform as described in claim 1, characterized in that: In step S2: Based on the coarse positioning in step S1, a set of data is sent to the six-degree-of-freedom motion platform. i Motion control commands for each point A set of one-to-one measurements were obtained. i Values ​​measured by the tracker at each point The measured values ​​are then used as parameters for the best fit in step S3.

4. The positioning method for the control center of a six-degree-of-freedom motion platform as described in claim 1, characterized in that: In step S4, the result obtained in step S3 is... Used to adjust the pose of the world coordinate system in the tracking measurement software; The control software used for the six-degree-of-freedom motion platform adjusts the pose of the control center of the six-degree-of-freedom motion platform.

Images