Design Method of Virtual Simulation System for Spacecraft Deployment Mechanism

Abstract

A method for designing a virtual simulation system for a spacecraft deployment mechanism belongs to the technical field of spacecraft deployment mechanism simulation. The present invention addresses the problem of long ground simulation cycle and poor flexibility of existing spacecraft deployment mechanisms. It includes the following steps: based on the 3D position coordinates of the world coordinate system of the feature points in the real scene point cloud model, the PnP algorithm is used to obtain the 2D position coordinates in the pixel coordinate system; combining the internal parameters of the AR device to obtain the first coordinate conversion matrix from the AR device coordinate system to the world coordinate system; then establishing a real space coordinate system, calculating the second coordinate conversion matrix from the AR device coordinate system to the real space coordinate system, and based on this, obtaining the position and posture of the virtual model of the deployment mechanism in the AR device coordinate system; fusing the virtual simulation framework with the real scene point cloud model to obtain a fused virtual framework, fixing the virtual model of the deployment mechanism on it to obtain a virtual simulation system, and rendering the selected rendering position in the real scene through the AR device. The present invention is used for the simulation of a spacecraft deployment mechanism.

Description

Technical Field

[0001] The invention relates to a virtual simulation system design method for a spacecraft deployment mechanism, and belongs to the technical field of spacecraft deployment mechanism simulation. Background Art

[0002] Traditional ground-based simulation experiments for large spacecraft deployment mechanisms rely on constructing complex, large-scale simulation mechanical structures. This approach has significant limitations. First, it is time-consuming. Building a supporting large-scale simulation mechanical structure platform is extremely time-consuming. From design and manufacturing to installation and commissioning, the entire process often takes months or even longer, significantly limiting the flexibility and responsiveness of the R&D cycle. Second, it is costly. The construction and maintenance costs of the simulation platform are extremely high. This includes not only the initial construction investment but also the subsequent operation and maintenance expenses. The high cost limits frequent experimentation and iteration, thereby affecting the speed and efficiency of technological advancement. Furthermore, this approach lacks flexibility. Once the simulation platform is built, its structure and functions are relatively fixed, making it difficult to adapt to the ever-changing needs of experimental simulations. This lack of flexibility limits the diversity and innovation of experimental designs.

[0003] Furthermore, existing research on deployment mechanism simulation primarily focuses on computer simulation, leveraging the powerful computing power of computers to acquire the required data. However, there are still some shortcomings in the visualization of simulations. During the project verification phase, experts from various fields are required to discuss and determine specific solutions. Relying solely on data makes it difficult for non-experts in the relevant fields to intuitively perceive the dynamic changes and details of the simulation process. Summary of the Invention

[0004] Aiming at the problems that the existing ground simulation cycle of spacecraft deployment mechanism is long and the flexibility is poor, the present invention provides a virtual simulation system design method for spacecraft deployment mechanism.

[0005] A virtual simulation system design method for a spacecraft deployment mechanism of the present invention includes:

[0006] Based on the real scene images captured by the AR device, a real scene point cloud model is established. Based on the 3D position coordinates of the feature points in the real scene point cloud model in the world coordinate system, the PnP algorithm is used to calculate the 2D position coordinates of the feature points in the real scene image in the pixel coordinate system. Combined with the AR device internal parameters, the first coordinate transformation matrix from the AR device coordinate system to the world coordinate system is calculated. The first coordinate transformation matrix is ​​used to determine the position and posture relationship of the AR device relative to the world coordinate system.

[0007] Create a spatial anchor point in the real scene and establish a real-space coordinate system based on the spatial anchor point; calculate a second coordinate transformation matrix from the AR device coordinate system to the real-space coordinate system; and calculate the position and orientation of the virtual model of the deployment mechanism in the AR device coordinate system based on the second coordinate transformation matrix and the selected rendering position of the virtual model of the deployment mechanism in the real-space coordinate system.

[0008] Establish a full-system data model of the spacecraft deployment mechanism and build a virtual simulation framework based on the full-system data model;

[0009] The virtual simulation framework is integrated with the point cloud model of the real scene to obtain a fused virtual framework; the virtual model of the unfolding mechanism is fixed on the fused virtual framework to form a virtual simulation system; and the AR device is enabled to render the selected rendering position in the real scene under the premise that the relative posture relationship of the world coordinate system is determined, thereby completing the construction of the virtual simulation system.

[0010] According to the method for designing a virtual simulation system for a spacecraft deployment mechanism of the present invention, after the virtual simulation system is built, the state switching of the deployment mechanism virtual model is controlled by driving force to achieve performance testing of the deployment mechanism virtual model.

[0011] According to the virtual simulation system design method for a spacecraft deployment mechanism of the present invention, the first coordinate transformation matrix is ​​expressed as [Rt], where R is a rotation parameter matrix and t is a translation parameter matrix;

[0012] Then the AR device coordinate system (O c X c Y c Z c ) and the world coordinate system (O w X w Y w Z w ) is:

[0013]

[0014] where [X w Y w Z w ] T is the 3D position coordinate of the feature point in the world coordinate system, and the corresponding homogeneous coordinate is [X w Y w Z w 1] T ;[X c Y c Z c ] T The 3D position coordinates of the feature point in the AR device coordinate system;

[0015] Set the 2D position coordinates of the feature point in the pixel coordinate system to [u c v c ] T , the corresponding homogeneous coordinates are [u c v c 1] T , the AR device internal parameter is K, then the pixel coordinate system and the world coordinate system (O w X w Y w Z w ) is:

[0016]

[0017] Where z c is the linear relationship coefficient from high dimension to low dimension;

[0018] Expand the above formula to get the expanded form:

[0019]

[0020] In the formula is the parameter coefficient in the rotation parameter matrix R, is the parameter coefficient in the translation parameter matrix t;

[0021] Express the expansion as a system of equations:

[0022] z c u c =f 11 X w +f 12 Y w +f 13 Z w +f 14 ,

[0023] z c v c =f 21 X w +f 22 Y w +f 23 Z w +f 24 ,

[0024] z c =f 31 X w +f 32 Y w +f 33 Z w +f 34 ,

[0025] Eliminate the linear relationship coefficient z from high dimension to low dimensionc Then we get:

[0026] f 11 X w +f 12 Y w +f 13 Z w +f 14 -f 31 X w u c -f 32 Y w u c -f 33 Z w u c -f 34 u c =0,

[0027] f 21 X w +f 22 Y w +f 23 Z w +f 24 -f 31 X w v c -f 32 Y w v c -f 33 Z w v c -f 34 v c =0,

[0028] Assume [u c v c ]There are N groups of matching points [u c1 v c1 ] to [u cN v cN ],[X w Y w Z w ]There are N sets of matching points [X w1 Y w1 Z w1 ] to [X wN Y wN Z wN ],get:

[0029]

[0030] Solved and

[0031] make

[0032] Combining F = [KR Kt], we get the rotation parameter matrix R and translation parameter matrix t:

[0033]

[0034]

[0035] According to the virtual simulation system design method of the spacecraft deployment mechanism of the present invention, the solution is obtained. and The methods include:

[0036] If N=6, solve the linear equations directly;

[0037] If N>6:

[0038] set up:

[0039]

[0040] Then AF=0;

[0041] Calculate the least squares solution under the constraint |F|=1, and then decompose A using the SVD method:

[0042] A=UDV T ,

[0043] Where A is a 2N×12 matrix, U is a 2N×2N matrix after decomposition, D is a 2N×12 matrix after decomposition, and V is a 12×12 matrix after decomposition; the last column of the matrix V is obtained and The solution.

[0044] According to the virtual simulation system design method of the spacecraft deployment mechanism of the present invention, the method of establishing the real space coordinate system is as follows:

[0045] Select spatial anchor points (A, B, C, D) corresponding to the feature points in the real scene, and establish a real space coordinate system based on the spatial anchor points;

[0046] In the AR device coordinate system, the three inconsistency plane anchor point vectors corresponding to the spatial anchor points (A, B, C, D) are:

[0047]

[0048] Where (a1, b1, c1) is the corresponding difference between the coordinate values ​​of spatial anchor point B and spatial anchor point A in the AR device coordinate system; (a2, b2, c2) is the corresponding difference between the coordinate values ​​of spatial anchor point C and spatial anchor point A in the AR device coordinate system; (a3, b3, c3) is the corresponding difference between the coordinate values ​​of spatial anchor point D and spatial anchor point A in the AR device coordinate system.

[0049] The Schmidt orthogonalization algorithm is used to orthogonally normalize the three inconsistency surface anchor point vectors:

[0050]

[0051] Take r = 3,

[0052]

[0053] in:

[0054] J1=a1 2 +b1 2 +c1 2 ,

[0055] J2=a2 2 +b2 2 +c2 2 ,

[0056] H1=a1a2+b1b2+c1c2,

[0057] H2=a1a3+b1b3+c1c3,

[0058] H3=a2a3+b2b3+c2c3,

[0059] standardization:

[0060]

[0061] In the real scene, the spatial anchor point A is used as the coordinate origin O r ,by The vector direction is X r Axis direction, The vector direction is Y r Axis direction, The vector direction is Z r Axis direction, establish the real space coordinate system (O r X r Y r Z r ).

[0062] The present invention has the following beneficial effects: The method implements virtual experiment simulation based on digital twins, further developing and improving simulation visualization technology. Using AR for reality enhancement, it presents the simulation process more intuitively and vividly, improving the practicality and authenticity of the simulation. The method can simulate large structural components without the need for a real experimental setup or environment, enabling early verification of ground simulation experiments. It also features a short simulation cycle and strong flexibility.

[0063] The method of the present invention is aimed at large-scale structural parts of spacecraft. It only needs to build a virtual simulation environment in a real site based on the PnP algorithm to verify the relevant content of the ground simulation experiment in advance, which can greatly shorten the engineering cycle and reduce engineering costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is a schematic diagram of the conversion relationship between the AR device coordinate system and the world coordinate system;

[0065] Figure 2 This is a diagram showing the relationship between the AR device coordinate system, the pixel coordinate system, and the world coordinate system. In the figure, f represents the AR device coordinate system, c represents the device coordinate system, and w represents the world coordinate system.

[0066] Figure 3 This is a schematic diagram of creating spatial anchor points in a real scene;

[0067] Figure 4 This is a schematic diagram of the orthogonal normalization of the three inequivalent surface anchor point vectors using the Schmidt orthogonalization algorithm in a real scene;

[0068] Figure 5 Is the real space coordinate system in the real scene (O r X r Z r Z r )

[0069] Figure 6 This is a rendering diagram of the virtual model of the deployment mechanism in the first orientation in the real space coordinate system;

[0070] Figure 7 This is a rendering diagram of the virtual model of the deployment mechanism in the second orientation in the real space coordinate system;

[0071] Figure 8 is a schematic diagram of a full system data model of an antenna in an embodiment;

[0072] Figure 9 Yes Figure 8 The model diagram after the full system data model is faceted;

[0073] Figure 10is a schematic diagram of a solidworks model of a ground deployment device in an embodiment;

[0074] Figure 11 is a schematic diagram of a single antenna for constructing a large antenna model in an embodiment;

[0075] Figure 12 Schematic diagram of a four-fold antenna used to construct a large antenna model in an embodiment;

[0076] Figure 13 is a schematic diagram of a large-scale antenna virtual model and a ground deployment virtual device in an embodiment;

[0077] Figure 14 It is a rendering effect diagram of the virtual simulation environment;

[0078] Figure 15 This is a schematic diagram of the folded state of the four-fold antenna in a virtual simulation environment;

[0079] Figure 16 This is a schematic diagram of a four-fold antenna unfolded once in a virtual simulation environment;

[0080] Figure 17 This is a schematic diagram of the secondary expansion of the four-fold antenna in a virtual simulation environment. DETAILED DESCRIPTION

[0081] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0082] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0083] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0084] Specific implementation method 1. Combination Figures 1 to 7 As shown, the present invention provides a virtual simulation system design method for a spacecraft deployment mechanism, comprising:

[0085] Based on the real scene images captured by the AR device, a real scene point cloud model is established. Based on the 3D position coordinates of the feature points in the real scene point cloud model in the world coordinate system, the PnP algorithm is used to calculate the 2D position coordinates of the feature points in the real scene image in the pixel coordinate system. Combined with the AR device internal parameters, the first coordinate transformation matrix from the AR device coordinate system to the world coordinate system is calculated. The first coordinate transformation matrix is ​​used to determine the position and posture relationship of the AR device relative to the world coordinate system.

[0086] Create a spatial anchor point in the real scene and establish a real-space coordinate system based on the spatial anchor point; calculate a second coordinate transformation matrix from the AR device coordinate system to the real-space coordinate system; and calculate the position and orientation of the virtual model of the deployment mechanism in the AR device coordinate system based on the second coordinate transformation matrix and the selected rendering position of the virtual model of the deployment mechanism in the real-space coordinate system.

[0087] Establish a full-system data model of the spacecraft deployment mechanism and build a virtual simulation framework based on the full-system data model;

[0088] The virtual simulation framework is integrated with the point cloud model of the real scene to obtain a fused virtual framework; the virtual model of the unfolding mechanism is fixed on the fused virtual framework to form a virtual simulation system; and the AR device is enabled to render the selected rendering position in the real scene under the premise that the relative posture relationship of the world coordinate system is determined, thereby completing the construction of the virtual simulation system.

[0089] In this implementation, the captured real-world scene images, including multi-dimensional photo sets or GoPro panoramic camera images, are used to generate a point cloud model of the real scene using a 3D reconstruction algorithm. Based on the feature points of the point cloud model, or feature points constructed by other methods, a Perspective-n-Point (PnP) algorithm is used to determine 3D to 2D corresponding points.

[0090] Furthermore, after the virtual simulation system is built, the state switching of the deployment mechanism virtual model is controlled by driving force to achieve performance testing of the deployment mechanism virtual model.

[0091] PnP describes how to estimate the pose of an AR device when N 3D feature points and their positions are known. If the 3D position of a feature point in two images is known, at least three point pairs (and at least one additional verification point) are required to calculate the motion of the AR device. The 3D position of the feature point can be determined from triangulation or a depth map from an RGB-D camera.

[0092] The geometric structure of the PnP problem is as follows Figure 1 As shown in the figure, given the coordinates of the 3D point and the corresponding 2D point and the intrinsic parameter matrix, the posture of the AR device is solved.

[0093] Known: coordinates of N points in the world coordinate system P1, P2...P N , corresponding point pixel coordinates p1, p2...p N , AR device internal reference K.

[0094] In this embodiment, combined with Figure 1 and Figure 2 As shown, the first coordinate transformation matrix is ​​expressed as [Rt], where R is the rotation parameter matrix and t is the translation parameter matrix;

[0095] Then the AR device coordinate system (O c X c Y c Z c ) and the world coordinate system (O w X w Y w Z w ) is:

[0096]

[0097] Assume that the AR device has been calibrated, where [X w Y w Z w ] T is the 3D position coordinate of the feature point in the world coordinate system, and the corresponding homogeneous coordinate is [X w Y w Z w 1] T ;[X c Y c Z c ] T The 3D position coordinates of the feature point in the AR device coordinate system;

[0098] Set the 2D position coordinates of the feature point in the pixel coordinate system to [U c V c ] T , the corresponding homogeneous coordinates are [U c V c 1] T , the AR device internal parameter is k, such as Figure 2 As shown, the pixel coordinate system and the world coordinate system (o w x w Y w Z w ) is:

[0099]

[0100] Where z c is the linear relationship coefficient from high dimension to low dimension;

[0101] Expand the above formula to get the expanded form:

[0102]

[0103] In the formula is the parameter coefficient in the rotation parameter matrix R, is the parameter coefficient in the translation parameter matrix t;

[0104] Express the expansion as a system of equations:

[0105] z c u c =F 11 X w +f 12 Y w +f 13 Z w +f 14 ,

[0106] z c v c =F 21 x w +f 22 Y w +f 23 Z w +f 24 ,

[0107] z c =F 31 x w +F 32 y w +F 33 z w +F 34 ,

[0108] Eliminate the linear relationship coefficient z from high dimension to low dimension c Then we get:

[0109] f 11 X w +F 12 y w +F 13 z w +f 14 -f 31 X w u c -f 32 Y w u c -f 33 Z w u c -f 34 u c =0,

[0110] f 21 X w +F 22 y w +F 23 z w +f 24 -f 31 X w v c -F 32 y w V c -F 33 z w v c -F 34 v c =0,

[0111] Each set of 3D-2D matching points corresponds to two equations, with a total of 12 unknowns, requiring at least 6 sets of matching points. c v c ]There are N groups of matching points [u c1 v c1 ] to [u cN v cN ],[X w Y w Z w ]There are N sets of matching points [X w1 Y w1 Z w1 ] to [X wN Y wN z wN ],get:

[0112]

[0113] Solved and make Combining F = [KR Kt], we get the rotation parameter matrix R and translation parameter matrix t:

[0114]

[0115] Solved and The methods include:

[0116] If N=6, solve the linear equations directly;

[0117] If N>6:

[0118] set up:

[0119]

[0120] Write the equation with N sets of matching points in matrix form, then AF=0;

[0121] Calculate the least squares solution under the constraint |F|=1, and then decompose A using the SVD method:

[0122] A=UDV T ,

[0123] Where A is a 2N×12 matrix, U is a 2N×2N matrix after decomposition, D is a 2N×12 matrix after decomposition, and V is a 12×12 matrix after decomposition; the last column of the matrix V is obtained and The solution.

[0124] Thus, a first coordinate conversion matrix from the AR device coordinate system to the world coordinate system is obtained, and the position relationship of the AR device relative to the world coordinate system is determined according to the first coordinate conversion matrix.

[0125] Virtual model positioning based on spatial anchor points and pose transformation:

[0126] To render a virtual model at a specific location in the real space, it is also necessary to convert the virtual model between the real space coordinate system and the AR device space coordinate system. First, a spatial anchor point must be created, and a real space coordinate system must be established based on the spatial anchor point. Then, based on the conversion relationship between the real space coordinate system and the AR device coordinate system, the position of the virtual model in the AR device coordinate system is calculated, and then the virtual model is rendered at a specific location.

[0127] To create a spatial anchor point:

[0128] Characteristics of spatial anchors: Spatial anchors are anchored to objects in real space based on feature point matching. They do not change with the position of the AR device and are only related to the position of the real object where the feature point is located. Figure 3 The spatial anchor point created.

[0129] Going further, combined Figures 3 to 7 As shown in the figure, the method to establish the real space coordinate system is:

[0130] Select spatial anchor points (A, B, C, D) corresponding to the feature points in the real scene, and establish a real space coordinate system based on the spatial anchor points;

[0131] In the AR device coordinate system, the three inconsistency plane anchor point vectors corresponding to the spatial anchor points (A, B, C, D) are:

[0132]

[0133] Where (a1, b1, c1) is the corresponding difference between the coordinate values ​​of spatial anchor point B and spatial anchor point A in the AR device coordinate system; (a2, b2, c2) is the corresponding difference between the coordinate values ​​of spatial anchor point C and spatial anchor point A in the AR device coordinate system; (a . ,b . ,c . ) is the corresponding difference between the coordinate values ​​of spatial anchor point D and spatial anchor point A in the AR device coordinate system;

[0134] like Figure 4 As shown, the Schmidt orthogonalization algorithm is used to orthogonally normalize the three inconsistency surface anchor point vectors:

[0135]

[0136] Because it is a three-dimensional space, take r = 3,

[0137]

[0138] in:

[0139] J1=a1 2 +b1 2 +c1 2 ,

[0140] J2=a2 2 +b2 2 +c2 2 ,

[0141] H1=a1a2+b1b2+c1c2,

[0142] H2=a1a3+b1b3+c1c3,

[0143] H3=a2a3+b2b3+c2c3,

[0144] standardization:

[0145]

[0146] In the real scene, the spatial anchor point A is used as the coordinate origin O r ,by The vector direction is X r Axis direction, The vector direction is Y r Axis direction, The vector direction is Z r Axis direction, establish the real space coordinate system (O r X r Y r Z r ),like Figure 5 Middle red coordinate system.

[0147] Going further, calculate the pose coordinates of the virtual model in the AR device coordinate system:

[0148] The method for calculating the second coordinate transformation matrix from the AR device coordinate system to the real space coordinate system is:

[0149] According to the establishment process of the real space coordinate system, the AR device coordinate system (O c X c Y c Z c ) and the real space coordinate system (O r X r Y r Z r ) is:

[0150]

[0151] Where M is the second coordinate transformation matrix:

[0152]

[0153] The pose coordinates of the virtual model of the unfolding mechanism in the AR device coordinate system are obtained.

[0154] The method for solving the pose coordinates of the virtual model of the unfolding mechanism in the AR device coordinate system is:

[0155] Assume that at a specific position in the real space, the coordinate system of the virtual model of the unfolding mechanism is ( b X b Y b Z b ), its position coordinate in the real space coordinate system is (X r1 ,Y r1 ,Z r1 ), the position of the virtual model of the unfolding mechanism in the real space coordinate system is expressed by four infinite numbers:

[0156] Solve the position coordinates (X c1 ,Y c1 ,Z c1 ):

[0157]

[0158] The coordinates of the body are (O b X b Y b Z b ) and the real space coordinate system (O r Xr Y r Z r ) is:

[0159]

[0160] Where Γ The coordinate transformation matrix from the real space coordinate system to the body coordinate system:

[0161]

[0162] Combining the second coordinate transformation matrix from the AR device coordinate system to the real space coordinate system, we can get the transformation relationship between the body coordinate system and the AR device coordinate system:

[0163]

[0164] In the formula To unfold the virtual model of the mechanism in the AR device coordinate system:

[0165]

[0166] The coordinate transformation matrix from the AR device coordinate system to the body coordinate system;

[0167] The equation obtained from the above conversion relationship is:

[0168]

[0169] Solve and obtain the pose of the virtual model of the unfolding mechanism in the AR device coordinate system

[0170] Figure 6 and Figure 7 The figure shows a test example. The pose of the virtual model of the unfolding mechanism is anchored to the real-space coordinate system. Changes in the AR device's pose do not change the pose of the virtual model of the unfolding mechanism. Instead, the pose of the virtual model of the unfolding mechanism in the AR device coordinate system is calculated and rendered in real time through an algorithm.

[0171] Going further, combined Figures 8 to 17 As shown, according to the application scenario, mission requirements and performance indicators of the spacecraft deployment mechanism, design data is established and documented to obtain a full system data model;

[0172] Establish a data conversion relationship between the full system data model and the virtual simulation framework, and use the 3dmax data interface to convert the full system data model into a virtual simulation framework through the Solidworks module.

[0173] The virtual simulation framework includes trusses, hangers, flip beams, and cylinders; the virtual simulation framework is fused with the real scene point cloud model to obtain a fused virtual framework;

[0174] The virtual model of the unfolding mechanism includes a hinge mechanism and a fixing frame;

[0175] The virtual model of the deployment mechanism is fixed on the fused virtual frame to form a virtual simulation system.

[0176] After the virtual simulation system is built, a driving force is added to the hinge mechanism of the virtual model of the unfolding mechanism, and a locking mechanism is added to the predetermined unfolding position of the virtual model of the unfolding mechanism to control the virtual model of the unfolding mechanism to unfold twice under the action of the driving force, thereby realizing the performance test of the virtual model of the unfolding mechanism.

[0177] Example:

[0178] Construction of virtual simulation framework based on unity3d:

[0179] Taking the deployment mechanism virtual model of a large antenna as an example, a full system data model of the large antenna is established:

[0180] A large-scale antenna full system data model is established based on the antenna's mission requirements and performance indicators. First, a detailed mathematical model is constructed based on the antenna system's application scenarios and performance indicators, such as communication distance, frequency range, gain, and beamwidth. Then, these subsystem models are integrated into a unified framework for the overall design of the large antenna. The accuracy of the model is preliminarily verified by testing with simulation software. Finally, the entire model is documented to form an antenna full system data model, such as Figure 8 shown.

[0181] Then, the data conversion between the large antenna full system data model (Pro / E, Solidworks and UG models) and the large antenna virtual model is realized, including the data content extracted from the large antenna full system data model and its storage format. The construction of the large antenna virtual model is mainly based on the 3dmax data interface technology. The 3dmax interface technology imports the three-dimensional model data in the Solidworks system through a neutral interface file and reconstructs the model data. The large antenna virtual model data adopts parametric patch data. The use of patched model data greatly improves the model display speed and can realize the rapid display of large data models, such as Figure 9 shown.

[0182] Construct a model of a large antenna ground deployment device:

[0183] First, use SolidWorks to build a ground deployment device model, including trusses, hangers, flip beams and cylinders, such as Figure 10 shown.

[0184] Build a large antenna model:

[0185] First, a single antenna board is modeled, such as Figure 11 As shown; then add the hinge mechanism and the fixed frame to obtain Figure 12 The large antenna shown is folded in four parts.

[0186] Virtual simulation environment construction

[0187] The four-fold large antenna model is fixed to the ground deployment device and assembled into a large antenna deployment full system data model. Then the data conversion between the large antenna full system data model (Pro / E, Solidworks and UG models) and the large antenna virtual model is realized, including the data content extracted from the large antenna full system data model and its storage format. The construction of the large antenna virtual model is mainly based on 3dmax data interface technology. The 3dmax interface technology imports the three-dimensional model data in the Solidworks system through a neutral interface file and reconstructs the model data. The large antenna virtual model data uses parametric patch data. The use of patched model data greatly improves the model display speed and can realize the rapid display of large data models. Figure 13 shown.

[0188] Import the virtual model into Unity and add a physics engine, such as adding driving force to the antenna connection hinge, adding collision properties, etc., to build a virtual simulation environment.

[0189] Virtual simulation system test:

[0190] The virtual simulation environment is rendered in the real space:

[0191] The constructed virtual simulation environment is integrated with the point cloud model, the program is packaged and copied into the AR device, and the program is run on the AR device to render and generate the virtual simulation environment. Figure 14 shown.

[0192] The four-fold antenna is unfolded in a virtual simulation environment:

[0193] After the virtual simulation environment is built, a driving force is added to the hinge, and a locking mechanism is added to the predetermined unfolding position to control the quadruple fold antenna to unfold twice under the action of the driving force. Figures 15 to 17 shown.

[0194] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It should be understood that many modifications may be made to the illustrative embodiments, and that other arrangements may be devised, without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in ways other than those described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in conjunction with other described embodiments.

Claims

1. A virtual simulation system design method for a spacecraft deployment mechanism, characterized in that: include: Based on the real scene images collected by AR devices, a real scene point cloud model is established; Based on the 3D position coordinates of feature points in the real scene point cloud model in the world coordinate system, the PnP algorithm is used to calculate the 2D position coordinates of feature points in the real scene image in the pixel coordinate system. Then, combined with the AR device internal parameters, the first coordinate transformation matrix from the AR device coordinate system to the world coordinate system is calculated. The first coordinate transformation matrix is ​​used to determine the position and posture relationship of the AR device relative to the world coordinate system. Create spatial anchor points in the real scene and establish a real space coordinate system based on the spatial anchor points; Calculate a second coordinate transformation matrix from the AR device coordinate system to the real space coordinate system; calculate the position and orientation of the virtual model of the deployment mechanism in the AR device coordinate system based on the second coordinate transformation matrix and the selected rendering position of the virtual model of the deployment mechanism in the real space coordinate system; Establish a full-system data model of the spacecraft deployment mechanism and build a virtual simulation framework based on the full-system data model; Fusing the virtual simulation framework with the real scene point cloud model to obtain a fused virtual framework; The virtual model of the unfolding mechanism is fixed on the fused virtual frame to form a virtual simulation system; under the premise that the position relationship of the AR device relative to the world coordinate system is determined, the virtual simulation system can render the selected rendering position in the real scene, thus completing the construction of the virtual simulation system.

2. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 1, characterized in that: After the virtual simulation system is built, the state switching of the deployment mechanism virtual model is controlled by driving force to achieve performance testing of the deployment mechanism virtual model.

3. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 2, wherein: The first coordinate transformation matrix is ​​expressed as [Rt], where R is the rotation parameter matrix and t is the translation parameter matrix; Then the AR device coordinate system (O c X c Y c Z c ) and the world coordinate system (O w X w Y w Z w ) is: where [X w Y w Z w ] T is the 3D position coordinate of the feature point in the world coordinate system, and the corresponding homogeneous coordinate is [X w Y w Z w 1] T ;[X c Y c Z c ] T The 3D position coordinates of the feature point in the AR device coordinate system; Set the 2D position coordinates of the feature point in the pixel coordinate system to [u c v c ] T , the corresponding homogeneous coordinates are [u c v c 1] T , the AR device internal parameter is K, then the pixel coordinate system and the world coordinate system (O w X w Y w Z w ) is: Where z c is the linear relationship coefficient from high dimension to low dimension; Expand the above formula to get the expanded form: In the formula is the parameter coefficient in the rotation parameter matrix R, is the parameter coefficient in the translation parameter matrix t; Express the expansion as a system of equations: z c u c =f 11 X w +f 12 Y w +f 13 Z w +f 14 , z c v c =f 21 X w +f 22 Y w +f 23 Z w +f 24 , z c =f 31 X w +f 32 Y w +f 33 Z w +f 34 , Eliminate the linear relationship coefficient z from high dimension to low dimension c Then we get: f 11 X w +f 12 Y w +f 13 Z w +f 14 -f 31 X w u c -f 32 Y w u c -f 33 Z w u c -f 34 u c =0, f 21 X w +f 22 Y w +f 23 Z w +f 24 -f 31 X w v c -f 32 Y w v c -f 33 Z w v c -f 34 v c =0, Assume [u c v c ]There are N groups of matching points [u c1 v c1 ] to [u cN v cN ],[X w Y w Z w ]There are N sets of matching points [X w1 Y w1 Z w1 ] to [X wN Y wN Z wN ],get: Solved and make Combining F = [KR Kt], we get the rotation parameter matrix R and translation parameter matrix t:

4. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 3, wherein: Solved and The methods include: If N=6, solve the linear equations directly; If N>6: set up: Then AF=0; Calculate the least squares solution under the constraint |F|=1, and then decompose A using the SVD method: A=UDV T , Where A is a 2N×12 matrix, U is a 2N×2N matrix after decomposition, D is a 2N×12 matrix after decomposition, and V is a 12×12 matrix after decomposition; the last column of the matrix V is obtained and The solution.

5. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 4, wherein: The method to establish the real space coordinate system is: Select spatial anchor points (A, B, C, D) corresponding to the feature points in the real scene, and establish a real space coordinate system based on the spatial anchor points; In the AR device coordinate system, the three inverse surface anchor point vectors corresponding to the spatial anchor points (A, B, C, D) are: Where (a1, b1, c1) is the corresponding difference between the coordinate values ​​of spatial anchor point B and spatial anchor point A in the AR device coordinate system; (a2, b2, c2) is the corresponding difference between the coordinate values ​​of spatial anchor point C and spatial anchor point A in the AR device coordinate system; (a3, b3, c3) is the corresponding difference between the coordinate values ​​of spatial anchor point D and spatial anchor point A in the AR device coordinate system. The Schmidt orthogonalization algorithm is used to orthogonally normalize the three inconsistency surface anchor point vectors: Take r = 3, in: J1=a1 2 +b1 2 +c1 2 , <h2 style=";text-align:left;direction:ltr">J2=a2<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> +b2<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> +c2<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> , H1=a1a2+b1b2+c1c2, H2=a1a3+b1b3+c1c3, H3=a2a3+b2b3+c2c3, standardization: In the real scene, the spatial anchor point A is used as the coordinate origin O r ,by The vector direction is X r Axis direction, The vector direction is Y r Axis direction, The vector direction is Z r Axis direction, establish the real space coordinate system (O r X r Y r Z r ).

6. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 5, characterized in that: The method for calculating the second coordinate transformation matrix from the AR device coordinate system to the real space coordinate system is: AR device coordinate system (O c X c Y c Z c ) and the real space coordinate system (O r X r Y r Z r ) is: Where M is the second coordinate transformation matrix: The pose coordinates of the virtual model of the unfolding mechanism in the AR device coordinate system are obtained.

7. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 6, wherein: The method for solving the pose coordinates of the virtual model of the unfolding mechanism in the AR device coordinate system is: Assume that the body coordinate system of the virtual model of the unfolding mechanism is ( b X b Y b Z b ), its position coordinate in the real space coordinate system is (X r1 ,Y r1 ,Z r1 ), the position of the virtual model of the unfolding mechanism in the real space coordinate system is expressed by four infinite numbers: Solve the position coordinates (X c1 ,Y c1 ,Z c1 ): The coordinates of the body are (O b X b Y b Z b ) and the real space coordinate system (O r X r Y r Z r ) is: In the formula The coordinate transformation matrix from the real space coordinate system to the body coordinate system: Combining the second coordinate transformation matrix from the AR device coordinate system to the real space coordinate system, we can get the transformation relationship between the body coordinate system and the AR device coordinate system: In the formula To unfold the virtual model of the mechanism in the AR device coordinate system: The coordinate transformation matrix from the AR device coordinate system to the body coordinate system; The equation obtained from the above conversion relationship is: Solve and obtain the pose of the virtual model of the unfolding mechanism in the AR device coordinate system 8. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 7, wherein: According to the application scenarios, mission requirements and performance indicators of the spacecraft deployment mechanism, design data is established and documented to obtain a full system data model; Establish a data conversion relationship between the full system data model and the virtual simulation framework, and use the 3dmax data interface to convert the full system data model into a virtual simulation framework through the Solidworks module.

9. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 8, wherein: The virtual simulation framework includes trusses, hangers, flip beams, and cylinders. The virtual simulation framework is integrated with the real scene point cloud model to obtain a fused virtual framework. The virtual model of the unfolding mechanism includes a hinge mechanism and a fixed frame. The virtual model of the deployment mechanism is fixed on the fused virtual frame to form a virtual simulation system.

10. The method for designing a virtual simulation system for a spacecraft deployment mechanism according to claim 9, wherein: After the virtual simulation system is built, a driving force is added to the hinge mechanism of the virtual model of the unfolding mechanism, and a locking mechanism is added to the predetermined unfolding position of the virtual model of the unfolding mechanism to control the virtual model of the unfolding mechanism to unfold twice under the action of the driving force, thereby realizing the performance test of the virtual model of the unfolding mechanism.

Images