Six-DOF Flexible Docking and Pose Measurement Platform and Its Usage Method

Abstract

This invention relates to the field of spacecraft ground simulation experiments, specifically a six-degree-of-freedom flexible docking and attitude measurement platform and its usage method. The platform includes a platform base, with three flexible mechanisms evenly distributed above the base. Each flexible mechanism has a support frame above it, and a docking mechanism mounting interface is fixedly connected to the support frame. Three cubes are evenly distributed on the lower surface of the docking mechanism mounting interface, and these cubes have six measurement reference planes forming three mutually perpendicular planes. A laser ranging unit is located on the opposite side of each measurement reference plane. In this invention, the flexible mechanisms effectively reduce problems such as position overshoot and force over-limit caused by slow response speeds of the actuators. Simultaneously, real-time six-degree-of-freedom attitude measurement is possible, and the attitude changes of the flexible mechanisms are integrated into the semi-physical measurement platform for calculation in real time, thereby eliminating motion distortion caused by the flexible mechanisms.

Description

Technical Field

[0001] This invention relates to the field of spacecraft ground simulation experiments, specifically a six-degree-of-freedom flexible docking and attitude measurement platform and its usage method. Background Technology

[0002] To test the docking performance of space docking mechanisms, ground-based experimental research and verification are generally required. Semi-physical testing, also known as hardware-in-the-loop testing, is a common method for testing the docking performance of space mechanisms on the ground. Semi-physical testing involves using a dynamic model to calculate the spacecraft's space docking dynamics, and then using the test bench actuator to execute the model's calculation results to drive the docking mechanism for docking. During the docking test, the active or passive docking mechanism is connected to the test bench actuator via a rigid mounting platform. Since semi-physical testing is a real-time dynamic simulation, it requires six-dimensional force sensors to acquire the six-dimensional force state of the docking mechanism in real time. The six-dimensional force measurement results are then fed into the dynamic model of the calculation unit for a new round of iteration. Therefore, the response speed and motion accuracy of the test bench actuator must be extremely high. However, existing test bench actuators are expensive, technically challenging, and prone to calculation distortion and even execution divergence, causing equipment damage. Therefore, a measurement platform is needed to reduce problems such as position overshoot and force over-limit caused by the slow response speed of the test bench actuator. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a six-degree-of-freedom flexible docking and pose measurement platform and its usage method. The addition of a flexible mechanism to the measurement platform effectively reduces problems such as position overshoot and force overshoot caused by the slow response speed of the actuator. Simultaneously, it enables real-time six-degree-of-freedom attitude measurement, integrating the attitude changes of the flexible mechanism into the semi-physical measurement platform for calculation, thereby eliminating motion distortion introduced by the flexible mechanism.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] A six-degree-of-freedom flexible docking and pose measurement platform includes a platform base, flexible mechanisms, a support frame, and a docking mechanism mounting interface. Three flexible mechanisms are evenly distributed above the platform base, and a support frame is mounted above each flexible mechanism. The docking mechanism mounting interface is fixedly connected to the support frame. Cubes I, II, and III are evenly distributed on the lower surface of the docking mechanism mounting interface. The bottom surfaces of cubes I, II, and III are all coplanar and serve as measurement reference surfaces. Measurement reference surface Measurement reference surface One side of cube I and one side of cube II are both used as measurement reference planes and are coplanar. The sides of cube I and cube II used as measurement reference planes are respectively the measurement reference planes. Measurement reference surface One side of cube III serves as measurement reference plane III, and is aligned with the measurement reference plane. Measurement reference surface Perpendicular to each other; measurement reference surface Measurement reference surface Measurement reference surface Measurement reference surface Measurement reference surface On the opposite side of the measurement reference plane III, there are laser ranging units I, II, III, IV, V, and VI, which are fixed on the platform base.

[0006] The flexible mechanism includes a rigid lower mounting plate, a flexible rubber plate, a rigid upper mounting plate, a rigid lower mounting frame, and a rigid upper cover. The rigid lower mounting plate and the rigid upper mounting plate are symmetrically fixed to the upper and lower surfaces of the middle part of the flexible rubber plate to press the middle part of the flexible rubber plate. The rigid lower mounting plate is fixed to the platform base through a connecting plate. The rigid upper cover and the rigid lower mounting frame are symmetrically fixed to the upper and lower surfaces of the edge of the flexible rubber plate. A gap is left between the middle part of the rigid upper cover and the flexible rubber plate. A flexible rubber connection is formed between the rigid upper cover and the rigid lower mounting plate. The top surface of the rigid upper cover is fixedly connected to the support frame.

[0007] A method for using a six-degree-of-freedom flexible docking and pose measurement platform includes the following steps:

[0008] The active or passive docking mechanism is connected to the docking mechanism via an interface installation.

[0009] When the active docking mechanism docks with the passive docking mechanism, the positional change of the docking mechanism's installation interface is measured;

[0010] The measurement reference surface is measured using laser ranging units I, II, III, IV, V, and VI. Measurement reference surface Measurement reference surface Measurement reference surface Measurement reference surface , Measurement of distance information from reference plane III;

[0011] The distance information is transmitted to the calculation unit of the semi-physical test platform to determine the six-degree-of-freedom pose of the docking mechanism installation interface, and the action of the test bench actuator is adjusted according to the six-degree-of-freedom pose of the docking mechanism installation interface.

[0012] Furthermore, the method for determining the six-degree-of-freedom pose of the docking mechanism's mounting interface includes the following steps:

[0013] Step 1: Establish a global Cartesian coordinate system, with the positive x-axis pointing vertically upwards and the y-axis pointing horizontally. The positive y-axis is aligned with the measurement reference plane. Measurement reference surface The directions of the normal vectors forming the plane are opposite, and the z-axis direction is determined according to the right-hand rule;

[0014] Step 2: Determine the transformation matrix of the docking mechanism's installation interface as it moves along the x-axis and rotates around the y-axis and z-axis;

[0015] Step 3: Determine the transformation matrix of the docking mechanism's installation interface as it moves along the y and z axes and rotates around the x-axis;

[0016] Step 4: Based on the transformation matrices of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis determined in Step 2, and the transformation matrices of the docking mechanism installation interface moving along the y and z axes and rotating around the x-axis determined in Step 3, determine the six-degree-of-freedom pose of the docking mechanism installation interface relative to the initial attitude.

[0017] Furthermore, the method for determining the transformation matrix of the docking mechanism installation interface as it moves along the x-axis and rotates around the y-axis and z-axis includes the following steps:

[0018] S1: Define the solution for points on a line The length function of the line segment from the intersection of the line and the plane. As shown in the formula below:

[0019] ;

[0020] In the formula, It is a point on a plane; It is a normalized plane normal vector; It is a point on a straight line; It is a vector representing the direction of a straight line; during function calculation, the spatial point N, It is believed that it starts from the origin and points to N. vector , Participate in calculation;

[0021] S2: Determine the measurement reference planes of cubes I, II, and III after the docking mechanism installation interface moves along the x-axis and rotates around the y-axis and z-axis. Measurement reference surface Measurement reference surface The normal vector of the resulting plane;

[0022] ;

[0023] In the formula, After the docking mechanism's installation interface moves along the x-axis and rotates around the y-axis and z-axis, the measurement reference surfaces of cubes I, II, and III are determined. Measurement reference surface Measurement reference surface The normal vector of the resulting plane; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the illumination point of the upper laser ranging unit I, After d1 is the installation interface of the docking mechanism, it moves along the x-axis and rotates around the y-axis and z-axis. The laser starting point of laser ranging unit I moves along the laser irradiation direction to the measurement reference surface. distance, The X-axis coordinate of the laser starting point of laser ranging unit I is given. Let y be the y-axis coordinate of the laser starting point of laser ranging unit I. The z-axis coordinate of the laser starting point of laser ranging unit I; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the laser ranging unit II's illumination point. After the mounting interface of the receiving mechanism moves along the x-axis and rotates around the y-axis and z-axis, the laser starting point of the laser ranging unit II moves along the laser irradiation direction to the measurement reference surface. distance, The X-axis coordinate of the laser starting point of laser ranging unit II is given. The y-axis coordinate of the laser starting point of laser ranging unit II; The z-axis coordinate of the laser starting point of laser ranging unit II; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the illumination point of the upper laser ranging unit III, After d3, the mounting interface of the docking mechanism, moves along the x-axis and rotates around the y-axis and z-axis, the laser starting point of laser ranging unit III moves along the laser irradiation direction to the measurement reference surface. The distance; The X-axis coordinate of the laser starting point of laser ranging unit III; The y-axis coordinate of the laser starting point of laser ranging unit III; The z-axis coordinate of the laser starting point of laser ranging unit III;

[0024] S3: Determine the displacement of the docking mechanism's installation interface along the x-axis;

[0025] ;

[0026] In the formula, I0 is the displacement of the docking mechanism mounting interface along the x-axis, and I0 is the measurement reference plane when the docking mechanism mounting interface is in its initial pose state. Measurement reference surface Measurement reference surface Form the coordinates of a point on a plane. ; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. Measurement reference surface Measurement reference surface The normal vector of the formed plane, ;

[0027] S4: Determine the direction vector and equivalent rotation angle of the equivalent rotation axis of the docking mechanism installation interface rotating around the y-axis and z-axis, and then determine the change matrix of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis, or determine the rotation angle of the docking mechanism installation interface rotating around the y-axis and z-axis, and then determine the change matrix of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis.

[0028] Furthermore, the method for determining the equivalent rotation angles of the docking mechanism mounting interface around the y-axis and z-axis, and thus determining the transformation matrix of the docking mechanism mounting interface moving along the x-axis and rotating around the y-axis and z-axis, includes the following steps:

[0029] A1: Determine the direction vectors of the equivalent rotation axes of the docking mechanism's installation interface around the y-axis and z-axis;

[0030] ;

[0031] In the formula, The direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis;

[0032] A2: The equivalent rotation angle is determined by the direction vector of the equivalent rotation axis of the docking mechanism installation interface rotating around the y-axis and z-axis;

[0033] ;

[0034] In the formula, The equivalent rotation angle of the mounting interface of the docking mechanism around the y-axis and z-axis;

[0035] A3: Based on the displacement of the docking mechanism installation interface along the x-axis obtained in step S3 and the equivalent rotation angles of the docking mechanism installation interface around the y-axis and z-axis obtained in step A2, determine the change matrix of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis.

[0036] ;

[0037] In the formula, The installation interface of the docking mechanism is configured to move along the x-axis and rotate around the y-axis and z-axis, and its transformation matrix is ​​provided. The x-axis component of the direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis; The y-axis component of the direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis; The z-axis component of the direction vector of the equivalent rotation axis of the interface of the docking mechanism rotating about the y-axis and z-axis.

[0038] Furthermore, the method for determining the rotation angles of the docking mechanism mounting interface around the y-axis and Z-axis, and thus determining the transformation matrix of the docking mechanism mounting interface moving along the x-axis and rotating around the y-axis and z-axis, includes the following steps:

[0039] B1: Determine the rotation matrix of the installation interface of the docking mechanism around the y-axis and z-axis;

[0040] ;

[0041] In the formula, A rotation matrix for mounting the interface of the docking mechanism around the y-axis and Z-axis; The rotation angle of the interface for the docking mechanism about the y-axis; The rotation angle of the mounting interface of the docking mechanism about the z-axis;

[0042] B2: After determining the installation interface of the docking mechanism and rotating it around the y-axis and Z-axis, measure the reference surface. Measurement reference surface Measurement reference surface The normal vector of the resulting plane;

[0043] ;

[0044] In the formula, After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The normal vector of the resulting plane;

[0045] B3: Determine the rotation angle of the docking mechanism's installation interface around the y-axis and Z-axis;

[0046] ;

[0047] In the formula, After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The z-axis component of the normal vector of the formed plane; After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The x-axis component of the normal vector of the formed plane. After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The y-axis component of the normal vector of the formed plane;

[0048] B4: Determine the transformation matrix of the installation interface of the docking mechanism along the x-axis and around the y-axis and z-axis based on the displacement of the installation interface along the x-axis obtained in step S3 and the rotation angle of the installation interface around the y-axis and z-axis obtained in step B3.

[0049] .

[0050] Furthermore, the method for determining the transformation matrix of the docking mechanism's installation interface as it moves along the y and z axes and rotates about the x-axis includes the following steps:

[0051] C1: The transformation matrix of the docking mechanism mounting interface moving along the y and z axes and rotating about the x-axis is:

[0052] ;

[0053] In the formula, The matrix for the installation interface of the docking mechanism to move along the y and z axes and rotate about the x axis; The angle by which the interface of the docking mechanism rotates about the x-axis. The displacement of the mounting interface of the docking mechanism along the y-axis. The displacement of the mounting interface of the docking mechanism along the z-axis;

[0054] C2: Determine the angle of rotation of the docking mechanism mounting interface around the x-axis, the displacement of the docking mechanism mounting interface along the y-axis, and the displacement of the docking mechanism mounting interface along the z-axis.

[0055] C21: Establish a measurement reference surface Measurement reference surface The equations governing the pose changes of the measurement reference plane III formed by the plane and cube III are as follows:

[0056] ;

[0057] In the formula, , , A rotation matrix for mounting the interface of the docking mechanism around the y-axis and z-axis; A rotation matrix for the installation interface of the docking mechanism to rotate about the x-axis; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The coordinates of points on the resulting plane , When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The y-coordinate of a point on the resulting plane; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The normal vector of the formed plane, When installing the interface of the docking mechanism in its initial pose state, measure the coordinates of points on reference plane III. , When installing the interface of the docking mechanism in its initial pose state, measure the y-axis coordinates of points on reference plane III. When installing the interface of the docking mechanism in its initial pose state, measure the z-axis coordinates of points on reference plane III; When the docking mechanism is in its initial pose at the installation interface, measure the normal vector of reference plane III; After the interface of the docking mechanism is moved along the y and z axes and rotated about the x axis, The coordinates of the point; After the docking mechanism's installation interface moves along the y and z axes and rotates about the x-axis, the reference surface is measured. With measurement reference plane The normal vector that forms the plane. After the interface of the docking mechanism is moved along the y and z axes and rotated about the x axis, The coordinates of the point; After the interface for the docking mechanism is moved along the y and z axes and rotated about the x axis, the normal vector of the reference plane III is measured.

[0058] C22: Establish laser ranging unit IV, laser ranging unit V, laser ranging unit VI, and the measurement reference plane. Measurement reference surface The system of equations relating the distance to the measurement reference plane III;

[0059] ;

[0060] In the formula, d4 represents the distance from the laser starting point of the laser ranging unit IV to the measurement reference surface after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis. The distance; d5 is the distance from the laser starting point of laser ranging unit V to the measurement reference surface after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis. The distance; d6 is the distance from the laser starting point of laser ranging unit VI to the measurement reference plane Ⅲ along the laser irradiation direction after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis; D0 is the coordinate of the laser starting point of laser ranging unit IV; E0 is the coordinate of the laser starting point of laser ranging unit V; F0 is the coordinate of the laser starting point of laser ranging unit VI. The direction vector of the laser irradiation direction of laser ranging unit VI; Let V be the direction vector of the laser irradiation direction of laser ranging unit IV and laser ranging unit V;

[0061] C23: Combine the equations from step C21 with the equations from step C22 to determine the angle of rotation of the docking mechanism mounting interface around the x-axis, the displacement of the docking mechanism mounting interface along the y-axis, and the displacement of the docking mechanism mounting interface along the z-axis.

[0062] ;

[0063] ;

[0064] in, ;

[0065] In the formula, The Z-axis coordinate of the laser starting point of laser ranging unit IV; The Z-axis coordinate of the laser starting point of laser ranging unit V; The direction vector of the laser starting point of laser ranging unit IV; The direction vector of the laser starting point of laser ranging unit V; The direction vector of the laser starting point of laser ranging unit VI; , , , , , These are intermediate variables, and T represents the matrix transpose.

[0066] Furthermore, the calculation method for the six-degree-of-freedom pose of the docking mechanism's installation interface relative to the initial attitude is as follows:

[0067] ;

[0068] In the formula, Install the interface of the docking mechanism in a six-degree-of-freedom pose relative to the initial attitude.

[0069] The beneficial effects of this invention are as follows:

[0070] 1. This invention provides a six-degree-of-freedom omnidirectional flexible platform, with each degree of freedom possessing flexible motion capabilities in both positive and negative directions, comprehensively reducing structural stiffness. The reduction in stiffness in the six-degree-of-freedom omnidirectional direction can effectively reduce the performance requirements of the test bench execution mechanism in semi-physical testing, improve the success rate of semi-physical testing, lower the threshold for building a semi-physical testing platform, reduce the requirements for the response speed of execution hardware, facilitate the verification of various technological innovations of the space docking mechanism, and at the same time, the high-precision real-time measurement of the six-degree-of-freedom attitude ensures the original authenticity of the semi-physical test.

[0071] 2. This invention enables non-contact real-time measurement of the six-degree-of-freedom attitude of the space docking mechanism relative to the platform foundation. While incorporating a flexible mechanism into the semi-physical testing platform solves the performance bottleneck of the actuator, the flexible mechanism itself introduces distortion for semi-physical testing. The combination of the cube and the laser ranging unit in this invention measures this distortion, providing the conditions for incorporating it into the semi-physical model simulation calculation, thereby eliminating the distortion. This achieves distortion-free flexible embedding of the semi-physical testing platform.

[0072] 3. This invention utilizes a rubber sheet to provide flexibility, reducing the design complexity and overall size of the flexible element. It also incorporates six-degree-of-freedom damping, meeting the requirements for flexible elements in semi-physical testing. Its structure ensures maximum flexibility in the docking direction, satisfying the flexibility requirements of docking tests.

[0073] 4. This invention significantly reduces the computational load of 6-DOF pose calculation by using pairwise perpendicular orthogonal measurement reference planes, thus meeting the real-time computation requirements of semi-physical testing. By distributing the measurement planes, the overall measurement accuracy of the 6-DOF pose is improved to the same order of magnitude as the distance measurement accuracy of a single sensor, reducing the need for high-precision six-dimensional force sensors. Attached Figure Description

[0074] Figure 1 This is a schematic diagram of the docking and pose measurement platform of the present invention;

[0075] Figure 2 This is a schematic diagram showing the attitude change of the installation interface of the docking mechanism of the docking and pose measurement platform of the present invention;

[0076] Figure 3 This is a cross-sectional structural diagram of the flexible mechanism of the docking and pose measurement platform of the present invention.

[0077] Figure 4An exploded view of the flexible mechanism of the docking and pose measurement platform of the present invention;

[0078] Figure 5 This is a schematic diagram of the coordinate system orientation of the docking and pose measurement platform of the present invention;

[0079] Figure 6 This is a diagram defining the six-DOF pose calculation variables for the docking and pose measurement platform of the present invention.

[0080] Figure 7 This is a flowchart of the six-degree-of-freedom pose calculation process for the docking and pose measurement platform of the present invention;

[0081] Figure 8 This is a connection diagram of the present invention applied to a semi-physical testing platform;

[0082] In the diagram: 1. Platform base; 2. Flexible mechanism; 201. Rigid lower mounting plate; 202. Flexible rubber plate; 203. Rigid upper mounting plate; 204. Rigid lower mounting frame; 205. Rigid upper cover; 3. Support frame; 4. Docking mechanism mounting interface; 401. Initial pose of the docking mechanism mounting interface; 402. Changed pose of the docking mechanism mounting interface; 5. Measurement reference plane; 501. Measurement reference plane. 502. Measurement reference surface 503. Measurement reference surface 504. Measurement reference surface 505. Measurement reference surface 506. Measurement reference surface III; 6. Laser ranging unit; 601. Laser ranging unit I; 602. Laser ranging unit II; 603. Laser ranging unit III; 604. Laser ranging unit IV; 605. Laser ranging unit V; 606. Laser ranging unit VI; 7. Cube I; 8. Cube II; 9. Cube III; 10. Active docking mechanism; 11. Passive docking mechanism; 12. Passive docking mechanism mounting fixture; 13. Six-dimensional force sensor. Detailed Implementation

[0083] The invention will now be described in further detail with reference to the accompanying drawings.

[0084] like Figures 1-5As shown, a six-degree-of-freedom flexible docking and pose measurement platform includes a platform base 1, flexible mechanisms 2, a support frame 3, and a docking mechanism mounting interface 4. Three flexible mechanisms 2 are evenly distributed above the platform base 1, and a support frame 3 is mounted above each flexible mechanism 2. The docking mechanism mounting interface 4 is fixedly connected to the support frame 3. Cubes I 7, II 8, and III 9 are evenly distributed on the lower surface of the docking mechanism mounting interface 4. The bottom surfaces of cubes I 7, II 8, and III 9 all serve as measurement reference surfaces 5 and are coplanar. 501. Measurement reference surface 502. Measurement reference surface 503; One side of cube I7 and one side of cube II8 are both used as measurement reference plane 5 and are coplanar. The sides of cube I7 and cube II8 used as measurement reference plane 5 are respectively the measurement reference planes. 504. Measurement reference surface 505, One side of cube Ⅲ9 serves as the measurement reference plane Ⅲ506, and is related to the measurement reference plane. 504. Measurement reference surface 501 are mutually perpendicular; measurement reference plane 501. Measurement reference surface 502. Measurement reference surface 503. Measurement reference surface 504. Measurement reference surface On the opposite sides of the measurement reference plane Ⅲ506, there are laser ranging units Ⅰ601, Ⅱ602, Ⅲ603, Ⅳ604, Ⅴ605, and Ⅵ606, which are fixed on the platform base.

[0085] In this embodiment, the platform base 1 serves as the foundation for the docking and pose measurement platform, and its body is as follows: Figure 1 The rigid disk shown. The platform base 1 is the mounting interface between this platform and the semi-physical testing bench during semi-physical testing applications, and also the mounting platform for all components of this invention. Three flexible mechanisms 2, equally spaced at 120° intervals on the platform base 1, provide six degrees of freedom flexibility and six degrees of freedom damping for the rigid assembly consisting of three support frames 3, a docking mechanism mounting interface 4, and three cubes mounted on it through a rigid-flexible coupling structure. The three support frames 3 support the docking mechanism mounting interface 4 to a certain height, providing space for the docking mechanism of the semi-physical testing. The docking mechanism mounting interface 4 provides a mounting interface for either an active or passive docking mechanism; such as... Figure 5As shown, the lower surfaces of cubes I7, II8, and III9 are coplanar, forming the yz plane of the measured coordinate system. One side surface of each of cubes I7, II8, and III9 is ​​selected as the measurement reference surface 5. 504. Measurement reference surface 505 is parallel to the zx plane of the measured coordinate system, and the measurement reference plane Ⅲ506 is parallel to the xy plane of the measured coordinate system. Six laser ranging units 6 measure the measurement reference planes in real time. 501. Measurement reference surface 502. Measurement reference surface 503. Measurement reference surface 504. Measurement reference surface 505. The six distances of the measurement reference plane Ⅲ506 are used to calculate the six-degree-of-freedom pose of the docking mechanism installation interface 4 relative to the initial pose. The six measurement reference planes 5 are divided into three groups of coplanar planes, which are perpendicular to each other. The layout and the three planes of the spatial rectangular coordinate system are parallel, which reduces the amount of calculation for the measurement structure and meets the real-time measurement requirements.

[0086] like Figure 8 As shown, in use, the measurement platform of this invention has the docking mechanism mounting interface connected to the active docking mechanism 10. The active docking mechanism 10 and the passive docking mechanism 11 are arranged opposite to each other. The passive docking mechanism 11 is connected to the test bench execution mechanism (not shown in this figure) through the passive docking mechanism mounting fixture 12, and a six-dimensional force sensor 13 is provided at its connection point. This invention is the mounting platform for the active docking mechanism 10, replacing the traditional rigid mounting platform, and providing a flexible mounting platform that can measure six degrees of freedom pose for semi-physical docking tests. The active docking mechanism and the passive docking mechanism are opposite to each other and can be interchanged according to actual needs. This invention can also be used for the installation of various other space docking mechanisms under test.

[0087] When the measurement platform of this invention is working, the docking mechanism mounting interface 4 is located from... Figure 2The initial pose 401 of the docking mechanism installation interface, as shown, is shifted to the changed pose 402 by an external force. This shift is due to the presence of the three flexible mechanisms 2. In a rigid connection, this shift would be a negligible pose, but even a small pose deviation in the test bench actuator can cause a significant deviation in the six-degree-of-freedom force, leading to severe distortion in the semi-physical model solution and placing very high demands on the test bench actuator. This application, by setting up the flexible mechanisms 2, can reduce the deviation in the six-degree-of-freedom force when the test bench actuator deviates from its motion, thereby reducing model solution distortion. However, this results in a large six-degree-of-freedom pose shift. By calculating the pose of the measurement platform of this invention and compensating for it in the semi-physical model solution, the excessive force state caused by the excessive movement of the semi-physical actuator is alleviated, thus mitigating the stress state exceeding the model calculation. Figure 2 It can be seen that the assembly of cubes I7, II8, III9 and the docking mechanism mounting interface 4 undergoes overall movement, i.e., the measurement reference plane... 501. Measurement reference surface 502. Measurement reference surface 503. Measurement reference surface 504. Measurement reference surface 505. When the pose of the measurement reference plane Ⅲ506 changes, the laser ranging units Ⅰ601, Ⅱ602, Ⅲ603, Ⅳ604, Ⅴ605, and Ⅵ606 can detect this motion offset and then calculate the six-degree-of-freedom pose of the docking mechanism's installation interface offset position relative to the initial position.

[0088] like Figure 3 , Figure 4 As shown, the flexible mechanism 2 includes a rigid lower mounting plate 201, a flexible rubber plate 202, a rigid upper mounting plate 203, a rigid lower mounting frame 204, and a rigid upper cover 205. The rigid lower mounting plate 201 and the rigid upper mounting plate 203 are symmetrically fixed to the upper and lower surfaces of the middle part of the flexible rubber plate 202 to press the middle part of the flexible rubber plate 202. The rigid lower mounting plate 201 is fixed to the platform base 1 through a connecting plate. The rigid upper cover 205 and the rigid lower mounting frame 204 are symmetrically fixed to the upper and lower surfaces of the edge of the flexible rubber plate 202. A gap is left between the middle part of the rigid upper cover 205 and the flexible rubber plate 202. A flexible rubber connection is formed between the rigid upper cover 205 and the rigid lower mounting plate 201. The top surface of the rigid upper cover 205 is fixedly connected to the support frame 3.

[0089] In this embodiment, the flexible mechanism 2 provides a flexible structure for the docking mechanism installation interface 4 relative to the platform base 1. The rigid-flexible coupling of the flexible mechanism 2 is achieved by the rigid lower mounting plate 201 and the rigid upper mounting plate 203 pressing the middle part of the flexible rubber plate 202 and connecting it to the platform base 1, and the rigid lower mounting frame 204 and the rigid upper cover 205 pressing the peripheral part of the flexible rubber plate 202 and connecting it to the support frame 3. The rigid upper mounting plate 203 has a movement space left inside the rigid upper cover 205, that is, a section of pure flexible rubber plate 202 is retained between the docking mechanism installation interface 4 and the platform base 1, thereby achieving flexibility.

[0090] A method for using a six-degree-of-freedom flexible docking and pose measurement platform includes the following steps:

[0091] The active or passive docking mechanism is connected to the docking mechanism via an interface installation.

[0092] When the active docking mechanism docks with the passive docking mechanism, the positional change of the docking mechanism's installation interface is measured;

[0093] The measurement reference surface is measured using laser ranging units I, II, III, IV, V, and VI. Measurement reference surface Measurement reference surface Measurement reference surface Measurement reference surface , Measurement of distance information from reference plane III;

[0094] The distance information is transmitted to the calculation unit of the semi-physical test platform to determine the six-degree-of-freedom pose of the docking mechanism installation interface, and the action of the test bench actuator is adjusted according to the six-degree-of-freedom pose of the docking mechanism installation interface.

[0095] like Figure 7 As shown, the method for determining the six-degree-of-freedom pose of the docking mechanism's mounting interface includes the following steps:

[0096] First, explain the meaning of the variables used to determine the six degrees of freedom pose of the docking mechanism's installation interface; such as... Figure 5 , Figure 6 As shown, the measurement reference surface 501. Measurement reference surface 502. Measurement reference surface 503 The three measurement reference planes are coplanar, which is Figure 6 plane in ,flat It is the yz plane of the coordinate system, the plane normal direction It is in the same direction as the x-axis; Figure 6 In , , All three points are on the plane. Above. Measurement reference surface 504 and measurement reference surface 505 are coplanar. Figure 6 plane G in Figure 6 In , All of them lie on plane G; yes , The midpoint of lies on plane G, which is parallel to the xz coordinate system. The normal vector is... Opposite to the y-axis; the measurement reference plane Ⅲ506 is Figure 6 plane H in Figure 6 In On plane H, On plane H, plane H is parallel to the coordinate system xy plane, and the normal vector is... Same as the z-axis. Laser ranging unit I 601, laser ranging unit II 602, laser ranging unit III 603, laser ranging unit IV 604, laser ranging unit V 605, and laser ranging unit VI 606 are respectively... Figure 6 In ~ Laser ranging unit I 601, laser ranging unit II 602, and laser ranging unit III 603 are configured according to... Figure 6 of Direction measurement to measurement reference plane Measurement reference surface Measurement reference surface The distance, laser ranging unit IV604 and laser ranging unit V605 according to Figure 6 of Direction measurement to measurement reference plane Measurement reference surface The distance, the laser ranging unit VI606 according to Figure 6 of The direction is measured to the distance from the measurement reference plane III.

[0097] The initial position of the active docking mechanism is recorded as 0. Due to the force applied to the active docking mechanism 10, the position after the installation interface of the docking mechanism of the present invention is deformed is recorded as 2.

[0098] Step 1: Establish a global Cartesian coordinate system, with the positive x-axis pointing vertically upwards and the y-axis pointing horizontally. The positive y-axis is aligned with the measurement reference plane. Measurement reference surface The directions of the normal vectors forming the plane are opposite, and the z-axis direction is determined according to the right-hand rule;

[0099] Step 2: Determine the transformation matrix of the docking mechanism's installation interface as it moves along the x-axis and rotates around the y-axis and z-axis;

[0100] Step 3: Determine the transformation matrix of the docking mechanism's installation interface as it moves along the y and z axes and rotates around the x-axis;

[0101] Step 4: Based on the transformation matrices of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis determined in Step 2, and the transformation matrices of the docking mechanism installation interface moving along the y and z axes and rotating around the x-axis determined in Step 3, determine the six-degree-of-freedom pose of the docking mechanism installation interface relative to the initial attitude.

[0102] Define function To find the point on the line The length of the line segment along the straight line to the intersection point of the plane, if from If a point reaches a plane along a straight line direction vector, the result is positive. It is a point on a plane. It is a normalized plane normal vector. It is a point on a straight line. It is a vector representing the direction of a straight line, and its function expansion is:

[0103] (1);

[0104] All vectors are free vectors, and all points can be represented by a vector originating from the origin and ending at that point, or by the coordinates of that point.

[0105] The method for determining the transformation matrix of the docking mechanism's installation interface as it moves along the x-axis and rotates around the y-axis and z-axis is based on the following general idea: First, utilize... , , These three known points determine a plane. In this transformation, the installation coordinate system of the docking mechanism is changed from its initial position. according to Move to , making The yz plane of the coordinate system and a defined plane Overlap, that is x-axis and plane Legal direction In the same direction, specifically including the following steps:

[0106] S1: In this transformation, only the x-translation is considered. After the installation interface of the docking mechanism moves along the x-axis and rotates around the y-axis and z-axis, the measurement reference planes of cubes I, II, and III are determined. Measurement reference surface Measurement reference surface The normal vector of the resulting plane;

[0107] (2);

[0108] In the formula, After the docking mechanism's installation interface moves along the x-axis and rotates around the y-axis and z-axis, the measurement reference surfaces of cubes I, II, and III are determined. Measurement reference surface Measurement reference surface The normal vector of the resulting plane; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the illumination point of the upper laser ranging unit I, After d1 is the installation interface of the docking mechanism, it moves along the x-axis and rotates around the y-axis and z-axis. The laser starting point of laser ranging unit I moves along the laser irradiation direction to the measurement reference surface. distance, The X-axis coordinate of the laser starting point of laser ranging unit I is given. Let y be the y-axis coordinate of the laser starting point of laser ranging unit I. The z-axis coordinate of the laser starting point of laser ranging unit I; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the laser ranging unit II's illumination point. After the mounting interface of the receiving mechanism moves along the x-axis and rotates around the y-axis and z-axis, the laser starting point of the laser ranging unit II moves along the laser irradiation direction to the measurement reference surface. distance, The X-axis coordinate of the laser starting point of laser ranging unit II is given. The y-axis coordinate of the laser starting point of laser ranging unit II; The z-axis coordinate of the laser starting point of laser ranging unit II; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the illumination point of the upper laser ranging unit III, After d3, the mounting interface of the docking mechanism, moves along the x-axis and rotates around the y-axis and z-axis, the laser starting point of laser ranging unit III moves along the laser irradiation direction to the measurement reference surface. The distance; The X-axis coordinate of the laser starting point of laser ranging unit III; The y-axis coordinate of the laser starting point of laser ranging unit III; The z-axis coordinate of the laser starting point of laser ranging unit III;

[0109] S2: Determine the displacement of the docking mechanism's installation interface along the x-axis;

[0110] (3);

[0111] In the formula, I0 is the displacement of the docking mechanism mounting interface along the x-axis, and I0 is the measurement reference plane when the docking mechanism mounting interface is in its initial pose state. Measurement reference surface Measurement reference surface Form the coordinates of a point on a plane. ; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. Measurement reference surface Measurement reference surface The normal vector of the formed plane, ;

[0112] The method for determining the transformation matrices of the docking mechanism's installation interface as it moves along the x-axis and rotates around the y-axis and z-axis by determining the direction vectors and equivalent rotation angles of the equivalent rotation axes of the interface's rotation around the y-axis and z-axis includes the following steps:

[0113] A1: Determine the direction vectors of the equivalent rotation axes of the docking mechanism's installation interface around the y-axis and z-axis;

[0114] (4);

[0115] In the formula, The direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis;

[0116] A2: The equivalent rotation angle is determined by the direction vector of the equivalent rotation axis of the docking mechanism installation interface rotating around the y-axis and z-axis;

[0117] (5);

[0118] In the formula, The equivalent rotation angle of the mounting interface of the docking mechanism around the y-axis and z-axis;

[0119] A3: Based on the displacement of the docking mechanism installation interface along the x-axis obtained in step S2 and the equivalent rotation angles of the docking mechanism installation interface around the y-axis and z-axis obtained in step A2, determine the change matrix of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis.

[0120] (6);

[0121] In the formula, The installation interface of the docking mechanism is configured to move along the x-axis and rotate around the y-axis and z-axis, and its transformation matrix is ​​provided. The x-axis component of the direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis; The y-axis component of the direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis; The z-axis component of the direction vector of the equivalent rotation axis of the interface of the docking mechanism rotating about the y-axis and z-axis.

[0122] The method for determining the rotation angles of the docking mechanism's mounting interface around the y-axis and Z-axis, and thus determining the transformation matrices of the docking mechanism's mounting interface moving along the x-axis and rotating around the y-axis and z-axis, includes the following steps:

[0123] B1: Determine the rotation matrix of the installation interface of the docking mechanism around the y-axis and z-axis;

[0124] (7);

[0125] In the formula, A rotation matrix for mounting the interface of the docking mechanism around the y-axis and Z-axis; The rotation angle of the interface for the docking mechanism about the y-axis; The rotation angle of the mounting interface of the docking mechanism about the z-axis;

[0126] B2: After determining the installation interface of the docking mechanism and rotating it around the y-axis and Z-axis, measure the reference surface. Measurement reference surface Measurement reference surface The normal vector of the resulting plane;

[0127] (8);

[0128] In the formula, After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The normal vector of the resulting plane; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. Measurement reference surface Measurement reference surface The normal vector of the resulting plane;

[0129] B3: Determine the rotation angle of the docking mechanism's installation interface around the y-axis and Z-axis;

[0130] (9);

[0131] In the formula, After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The z-axis component of the normal vector of the formed plane; After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The x-axis component of the normal vector of the formed plane. After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The y-axis component of the normal vector of the formed plane.

[0132] B4: Based on the displacement of the installation interface of the docking mechanism along the x-axis obtained in step S2 and the rotation angle of the installation interface around the y-axis and Z-axis obtained in step B3, determine the change matrix of the installation interface of the docking mechanism moving along the x-axis and rotating around the y-axis and Z-axis.

[0133] (10);

[0134] For the first step, we use three ranging results , , Transform the coordinate system so that the yz plane and the plane Coincident, the coordinate system can be in this plane Upward translation and around the plane normal Rotation, three measurement results , , It remains unchanged. Therefore, the essence of the second step is through... , , Three measurement data points determine the final state of the coordinate system. The unknowns to be solved are then used. , , Represent the transformation in the second step.

[0135] The method for determining the transformation matrix of the docking mechanism's installation interface as it moves along the y and z axes and rotates around the x axis specifically includes the following steps:

[0136] C1: The transformation matrix of the docking mechanism mounting interface moving along the y and z axes and rotating about the x-axis is:

[0137] (11);

[0138] In the formula, The matrix for the installation interface of the docking mechanism to move along the y and z axes and rotate about the x axis; The angle by which the interface of the docking mechanism rotates about the x-axis. The displacement of the mounting interface of the docking mechanism along the y-axis. The displacement of the mounting interface of the docking mechanism along the z-axis;

[0139] C2: Determine the angle of rotation of the docking mechanism mounting interface around the x-axis, the displacement of the docking mechanism mounting interface along the y-axis, and the displacement of the docking mechanism mounting interface along the z-axis;

[0140] C21: Establish a measurement reference surface Measurement reference surface The equations governing the pose changes of the measurement reference plane III formed by the plane and cube III are as follows:

[0141] (12);

[0142] In the formula, , , A rotation matrix for mounting the interface of the docking mechanism around the y-axis and z-axis; A rotation matrix for the installation interface of the docking mechanism to rotate about the x-axis; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The coordinates of points on the resulting plane , When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The y-coordinate of a point on the resulting plane; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The normal vector of the formed plane, When installing the interface of the docking mechanism in its initial pose state, measure the coordinates of points on reference plane III. , When installing the interface of the docking mechanism in its initial pose state, measure the y-axis coordinates of points on reference plane III. When installing the interface of the docking mechanism in its initial pose state, measure the z-axis coordinates of points on reference plane III; When the docking mechanism is in its initial pose at the installation interface, measure the normal vector of reference plane III; After the interface of the docking mechanism is moved along the y and z axes and rotated about the x axis, The coordinates of the point; After the docking mechanism's installation interface moves along the y and z axes and rotates about the x-axis, the reference surface is measured. With measurement reference plane The normal vector that forms the plane. After the interface of the docking mechanism is moved along the y and z axes and rotated about the x axis, The coordinates of the point; After the interface for the docking mechanism is moved along the y and z axes and rotated about the x axis, the normal vector of the reference plane III is measured.

[0143] , , , The unknown to be solved , , The function will measure the reference surface. Measurement reference surface Expanding the first and third equations of the pose change of the measurement reference plane III formed by the plane and cube III, we obtain the function expression:

[0144] (13);

[0145] (14);

[0146] C22: Establish laser ranging unit IV, laser ranging unit V, laser ranging unit VI, and the measurement reference plane. Measurement reference surface The system of equations relating the distance to the measurement reference plane III;

[0147] (15);

[0148] In the formula, d4 represents the distance from the laser starting point of the laser ranging unit IV to the measurement reference surface after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis. The distance d5 is the distance from the laser starting point of laser ranging unit V to the measurement reference surface after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis. The distances are as follows: d6 is the distance from the laser starting point of laser ranging unit VI to the measurement reference plane Ⅲ along the laser irradiation direction after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis; D0 is the coordinate of the laser starting point of laser ranging unit IV; E0 is the coordinate of the laser starting point of laser ranging unit V; and F0 is the coordinate of the laser starting point of laser ranging unit VI. The direction vector of the laser irradiation direction of laser ranging unit VI; is the direction vector of the laser irradiation direction of laser ranging unit IV and laser ranging unit V.

[0149] Expanding and rearranging the system of equations f from step C22, we obtain:

[0150] (16);

[0151] C23: Combine the equations from step C21 and C22 to determine the angle of rotation of the docking mechanism mounting interface around the x-axis, the displacement of the docking mechanism mounting interface along the y-axis, and the displacement of the docking mechanism mounting interface along the z-axis. , , available ;

[0152] , , , , , , , Known numbers, unknown numbers Included , , , In the middle, unknowns , Included , In the middle. If the first equation and the second equation of formula (16) are subtracted, a result is obtained only in terms of the unknown. The equation can be solved. After solving... , Also known numbers, the first equation and the third equation of formula (16) are about the unknowns. , The two equations can also be solved, specifically:

[0153] (1) Solving for the unknown ;

[0154] Subtracting equation 1 and equation 2 from equation (16) gives:

[0155] (17);

[0156] Will , , , , , Substituting into formula (17) and expanding the matrix, we get:

[0157] (18);

[0158] In the formula, The x-axis coordinate of the laser starting point of laser ranging unit IV; The y-axis coordinate of the laser starting point of laser ranging unit IV; The x-axis coordinate of the laser starting point of laser ranging unit V; The y-axis coordinate of the laser starting point of laser ranging unit V; The Z-axis coordinate of the laser starting point of laser ranging unit IV; The Z-axis coordinate of the laser starting point of laser ranging unit V; The x-axis component of the direction vector of the laser irradiation direction of laser ranging unit IV and laser ranging unit V; The y-axis component of the direction vector of the laser irradiation direction of laser ranging unit IV and laser ranging unit V; The z-axis component of the direction vector of the laser irradiation direction of laser ranging unit IV and laser ranging unit V;

[0159] (2) Solving for the unknown , ;

[0160] Adding the first and second equations of formula (16), and then combining them with the third equation of formula (16), we get,

[0161] (19);

[0162] Formula (13) And formula (14) Substituting the expression, we get:

[0163] (20);

[0164] Further,

[0165] (twenty one);

[0166] (twenty two);

[0167] In the formula, The direction vector of the laser starting point of laser ranging unit IV; The direction vector of the laser starting point of laser ranging unit V; The direction vector of the laser starting point of laser ranging unit VI; , , , , , These are intermediate variables, and T represents the matrix transpose.

[0168] The calculation method for determining the six-degree-of-freedom pose of the docking mechanism's installation interface relative to its initial attitude is as follows:

[0169] (twenty three);

[0170] In the formula, Install the interface of the docking mechanism in a six-degree-of-freedom pose relative to the initial attitude.

Claims

1. A six-degree-of-freedom flexible docking and pose measurement platform, characterized in that, The system includes a platform base, flexible mechanisms, support frames, and docking mechanism mounting interfaces. Three flexible mechanisms are evenly distributed above the platform base, each with a support frame above it. The docking mechanism mounting interfaces are fixedly connected to the support frames. Cubes I, II, and III are evenly distributed on the lower surface of the docking mechanism mounting interfaces. The bottom surfaces of cubes I, II, and III are all coplanar and serve as measurement reference surfaces. Measurement reference surface Measurement reference surface One side of cube I and one side of cube II are both used as measurement reference planes and are coplanar. The sides of cube I and cube II used as measurement reference planes are respectively the measurement reference planes. Measurement reference surface One side of cube III serves as measurement reference plane III, and is aligned with the measurement reference plane. Measurement reference surface Perpendicular to each other; measurement reference surface Measurement reference surface Measurement reference surface Measurement reference surface Measurement reference surface On the opposite side of the measurement reference plane III, there are laser ranging units I, II, III, IV, V, and VI, which are fixed on the platform base.

2. The six-degree-of-freedom flexible docking and pose measurement platform according to claim 1, characterized in that, The flexible mechanism includes a rigid lower mounting plate, a flexible rubber plate, a rigid upper mounting plate, a rigid lower mounting frame, and a rigid upper cover. The rigid lower mounting plate and the rigid upper mounting plate are symmetrically fixed to the upper and lower surfaces of the middle part of the flexible rubber plate to press the middle part of the flexible rubber plate. The rigid lower mounting plate is fixed to the platform base through a connecting plate. The rigid upper cover and the rigid lower mounting frame are symmetrically fixed to the upper and lower surfaces of the edge of the flexible rubber plate. A gap is left between the middle part of the rigid upper cover and the flexible rubber plate. A flexible rubber connection is formed between the rigid upper cover and the rigid lower mounting plate. The top surface of the rigid upper cover is fixedly connected to the support frame.

3. A method for using a six-degree-of-freedom flexible docking and pose measurement platform, characterized in that, The six-degree-of-freedom flexible docking and pose measurement platform described in claim 1 includes the following steps: The active or passive docking mechanism is connected to the docking mechanism via an interface installation. When the active docking mechanism docks with the passive docking mechanism, the positional change of the docking mechanism's installation interface is measured; The measurement reference surface is measured using laser ranging units I, II, III, IV, V, and VI. Measurement reference surface Measurement reference surface Measurement reference surface Measurement reference surface , Measurement of distance information from reference plane III; The distance information is transmitted to the calculation unit of the semi-physical test platform to determine the six-degree-of-freedom pose of the docking mechanism installation interface, and the action of the test bench actuator is adjusted according to the six-degree-of-freedom pose of the docking mechanism installation interface.

4. The method of using the six-degree-of-freedom flexible docking and pose measurement platform according to claim 3, characterized in that, The method for determining the six-degree-of-freedom pose of the docking mechanism installation interface includes the following steps: Step 1: Establish a global Cartesian coordinate system, with the positive x-axis pointing vertically upwards and the y-axis pointing horizontally. The positive y-axis is aligned with the measurement reference plane. Measurement reference surface The directions of the normal vectors forming the plane are opposite, and the z-axis direction is determined according to the right-hand rule; Step 2: Determine the transformation matrix of the docking mechanism's installation interface as it moves along the x-axis and rotates around the y-axis and z-axis; Step 3: Determine the transformation matrix of the docking mechanism's installation interface as it moves along the y and z axes and rotates around the x-axis; Step 4: Based on the transformation matrices of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis determined in Step 2, and the transformation matrices of the docking mechanism installation interface moving along the y and z axes and rotating around the x-axis determined in Step 3, determine the six-degree-of-freedom pose of the docking mechanism installation interface relative to the initial attitude.

5. The method of using the six-degree-of-freedom flexible docking and pose measurement platform according to claim 4, characterized in that, The method for determining the transformation matrix of the docking mechanism's installation interface as it moves along the x-axis and rotates around the y-axis and z-axis includes the following steps: S1: Define the solution for points on a line The length function of the line segment from the intersection of the line and the plane. As shown in the formula below: ； In the formula, It is a point on a plane; It is a normalized plane normal vector; It is a point on a straight line; It is a vector representing the direction of a straight line; during function calculation, the spatial point N, It is believed that it starts from the origin and points to N. vector , Participate in calculation; S2: Determine the measurement reference planes of cubes I, II, and III after the docking mechanism installation interface moves along the x-axis and rotates around the y-axis and z-axis. Measurement reference surface Measurement reference surface The normal vector of the resulting plane; ； In the formula, After the docking mechanism's installation interface moves along the x-axis and rotates around the y-axis and z-axis, the measurement reference surfaces of cubes I, II, and III are determined. Measurement reference surface Measurement reference surface The normal vector of the resulting plane; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the illumination point of the upper laser ranging unit I, After d1 is the installation interface of the docking mechanism, it moves along the x-axis and rotates around the y-axis and z-axis. The laser starting point of laser ranging unit I moves along the laser irradiation direction to the measurement reference surface. distance, The X-axis coordinate of the laser starting point of laser ranging unit I is given. Let y be the y-axis coordinate of the laser starting point of laser ranging unit I. The z-axis coordinate of the laser starting point of laser ranging unit I; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the laser ranging unit II's illumination point. After the mounting interface of the receiving mechanism moves along the x-axis and rotates around the y-axis and z-axis, the laser starting point of the laser ranging unit II moves along the laser irradiation direction to the measurement reference surface. distance, The X-axis coordinate of the laser starting point of laser ranging unit II is given. The y-axis coordinate of the laser starting point of laser ranging unit II; The z-axis coordinate of the laser starting point of laser ranging unit II; After the interface of the docking mechanism is moved along the x-axis and rotated around the y-axis and z-axis, the reference surface is measured. The coordinates of the illumination point of the upper laser ranging unit III, After d3, the mounting interface of the docking mechanism, moves along the x-axis and rotates around the y-axis and z-axis, the laser starting point of laser ranging unit III moves along the laser irradiation direction to the measurement reference surface. The distance; The X-axis coordinate of the laser starting point of laser ranging unit III; The y-axis coordinate of the laser starting point of laser ranging unit III; The z-axis coordinate of the laser starting point of laser ranging unit III; S3: Determine the displacement of the docking mechanism's installation interface along the x-axis; ； In the formula, I0 is the displacement of the docking mechanism mounting interface along the x-axis, and I0 is the measurement reference plane when the docking mechanism mounting interface is in its initial pose state. Measurement reference surface Measurement reference surface Form the coordinates of a point on a plane. ; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. Measurement reference surface Measurement reference surface The normal vector of the formed plane, ; S4: Determine the direction vector and equivalent rotation angle of the equivalent rotation axis of the docking mechanism installation interface rotating around the y-axis and z-axis, and then determine the change matrix of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis, or determine the rotation angle of the docking mechanism installation interface rotating around the y-axis and z-axis, and then determine the change matrix of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis.

6. The method of using the six-degree-of-freedom flexible docking and pose measurement platform according to claim 5, characterized in that, The method for determining the direction vectors and equivalent rotation angles of the equivalent rotation axes of the docking mechanism's installation interface around the y-axis and z-axis, and then determining the transformation matrices of the docking mechanism's installation interface moving along the x-axis and rotating around the y-axis and z-axis, includes the following steps: A1: Determine the direction vectors of the equivalent rotation axes of the docking mechanism's installation interface around the y-axis and z-axis; ； In the formula, The direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis; A2: The equivalent rotation angle is determined by the direction vector of the equivalent rotation axis of the docking mechanism installation interface rotating around the y-axis and z-axis; ； In the formula, The equivalent rotation angle of the mounting interface of the docking mechanism around the y-axis and z-axis; A3: Based on the displacement of the docking mechanism installation interface along the x-axis obtained in step S3 and the equivalent rotation angles of the docking mechanism installation interface around the y-axis and z-axis obtained in step A2, determine the change matrix of the docking mechanism installation interface moving along the x-axis and rotating around the y-axis and z-axis. ； In the formula, The installation interface of the docking mechanism is configured to move along the x-axis and rotate around the y-axis and z-axis, and its transformation matrix is ​​provided. The x-axis component of the direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis; The y-axis component of the direction vector of the equivalent rotation axis for the installation interface of the docking mechanism to rotate about the y-axis and z-axis; The z-axis component of the direction vector of the equivalent rotation axis of the interface of the docking mechanism rotating about the y-axis and z-axis.

7. The method of using the six-degree-of-freedom flexible docking and pose measurement platform according to claim 5, characterized in that, The method for determining the rotation angles of the docking mechanism's mounting interface around the y-axis and Z-axis, and thus determining the transformation matrices of the docking mechanism's mounting interface moving along the x-axis and rotating around the y-axis and z-axis, includes the following steps: B1: Determine the rotation matrix of the installation interface of the docking mechanism around the y-axis and z-axis; ； In the formula, A rotation matrix for mounting the interface of the docking mechanism around the y-axis and Z-axis; The rotation angle of the interface for the docking mechanism about the y-axis; The rotation angle of the mounting interface of the docking mechanism about the z-axis; B2: After determining the installation interface of the docking mechanism and rotating it around the y-axis and Z-axis, measure the reference surface. Measurement reference surface Measurement reference surface The normal vector of the resulting plane; ； In the formula, After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The normal vector of the resulting plane; B3: Determine the rotation angle of the docking mechanism's installation interface around the y-axis and Z-axis; ； In the formula, After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The z-axis component of the normal vector of the formed plane; After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The x-axis component of the normal vector of the formed plane. After the interface of the docking mechanism is rotated around the y-axis and Z-axis, the reference surface is measured. Measurement reference surface Measurement reference surface The y-axis component of the normal vector of the formed plane; B4: Determine the transformation matrix of the installation interface of the docking mechanism along the x-axis and around the y-axis and z-axis based on the displacement of the installation interface along the x-axis obtained in step S3 and the rotation angle of the installation interface around the y-axis and z-axis obtained in step B3. 。 8. The method of using the six-degree-of-freedom flexible docking and pose measurement platform according to claim 6 or claim 7, characterized in that, The method for determining the transformation matrix of the docking mechanism's installation interface as it moves along the y and z axes and rotates about the x-axis includes the following steps: C1: The transformation matrix of the docking mechanism mounting interface moving along the y and z axes and rotating about the x-axis is: ； In the formula, The matrix for the installation interface of the docking mechanism to move along the y and z axes and rotate about the x axis; The angle by which the interface of the docking mechanism rotates about the x-axis. The displacement of the mounting interface of the docking mechanism along the y-axis. The displacement of the mounting interface of the docking mechanism along the z-axis; C2: Determine the angle of rotation of the docking mechanism mounting interface around the x-axis, the displacement of the docking mechanism mounting interface along the y-axis, and the displacement of the docking mechanism mounting interface along the z-axis. C21: Establish a measurement reference surface Measurement reference surface The equations governing the pose changes of the measurement reference plane III formed by the plane and cube III are as follows: ； In the formula, , , A rotation matrix for mounting the interface of the docking mechanism around the y-axis and z-axis; A rotation matrix for the installation interface of the docking mechanism to rotate about the x-axis; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The coordinates of points on the resulting plane , When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The y-coordinate of a point on the resulting plane; When installing the interface of the docking mechanism in its initial pose state, the reference plane is measured. and measurement reference surface The normal vector of the formed plane, When installing the interface of the docking mechanism in its initial pose state, measure the coordinates of points on reference plane III. , When installing the interface of the docking mechanism in its initial pose state, measure the y-axis coordinates of points on reference plane III. When installing the interface of the docking mechanism in its initial pose state, measure the z-axis coordinates of points on reference plane III; When the docking mechanism is in its initial pose at the installation interface, measure the normal vector of reference plane III; After the interface of the docking mechanism is moved along the y and z axes and rotated about the x axis, The coordinates of the point; After the docking mechanism's installation interface moves along the y and z axes and rotates about the x-axis, the reference surface is measured. With measurement reference plane The normal vector that forms the plane. After the interface of the docking mechanism is moved along the y and z axes and rotated about the x axis, The coordinates of the point; After the interface for the docking mechanism is moved along the y and z axes and rotated about the x axis, the normal vector of the reference plane III is measured. C22: Establish laser ranging unit IV, laser ranging unit V, laser ranging unit VI, and the measurement reference plane. Measurement reference surface The system of equations relating the distance to the measurement reference plane III; ； In the formula, d4 represents the distance from the laser starting point of the laser ranging unit IV to the measurement reference surface after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis. The distance; d5 is the distance from the laser starting point of laser ranging unit V to the measurement reference surface after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis. The distance; d6 is the distance from the laser starting point of laser ranging unit VI to the measurement reference plane Ⅲ along the laser irradiation direction after the docking mechanism installation interface moves along the y and z axes and rotates around the x axis; D0 is the coordinate of the laser starting point of laser ranging unit IV; E0 is the coordinate of the laser starting point of laser ranging unit V; F0 is the coordinate of the laser starting point of laser ranging unit VI. The direction vector of the laser irradiation direction of laser ranging unit VI; Let V be the direction vector of the laser irradiation direction of laser ranging unit IV and laser ranging unit V; C23: Combine the equations from step C21 with the equations from step C22 to determine the angle of rotation of the docking mechanism mounting interface around the x-axis, the displacement of the docking mechanism mounting interface along the y-axis, and the displacement of the docking mechanism mounting interface along the z-axis. ； ； in, ; In the formula, The Z-axis coordinate of the laser starting point of laser ranging unit IV; The Z-axis coordinate of the laser starting point of laser ranging unit V; The direction vector of the laser starting point of laser ranging unit IV; The direction vector of the laser starting point of laser ranging unit V; The direction vector of the laser starting point of laser ranging unit VI; , , , , , These are intermediate variables, and T represents the matrix transpose.

9. The method of using the six-degree-of-freedom flexible docking and pose measurement platform according to claim 8, characterized in that, The calculation method for determining the six-degree-of-freedom pose of the docking mechanism's installation interface relative to its initial attitude is as follows: ； In the formula, Install the interface of the docking mechanism in a six-degree-of-freedom pose relative to the initial attitude.

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