Automatic modeling method for space assembly process of variable topology spaceflight structure

Abstract

The embodiment of the invention discloses an automatic modeling method for the space assembly process of a variable topology spaceflight structure, and the method achieves the automatic modeling of the space assembly process of the variable topology spaceflight structure, carries out the updating and solving of an overall structure kinetic equation through the execution of a plurality of assembly modeling processes, can achieve the building of a dynamic model, and achieves the automatic modeling of the space assembly process of the variable topology spaceflight structure. Automatic expansion and updating of a dynamic model in the space assembling process are achieved, the dynamic evolution law of the variable topology structure in the assembling process is represented, and therefore the space assembling process of the variable topology spaceflight structure is accurately simulated, the modeling efficiency and accuracy can be improved, a large amount of data and complex assembling logic can be effectively processed, and the space assembling efficiency is improved. Powerful theoretical support is provided for on-orbit assembly of a variable topology aerospace structure, a theoretical basis is provided for on-orbit assembly dynamics evolution analysis, and the method has important engineering application value. The method is widely applied to the technical field of computer software.

Description

Technical Field

[0001] The embodiments of the present invention relate to the fields of computer software technology and aerospace dynamics, and in particular to an automated modeling method for the space assembly process of variable topology aerospace structures. Background Technology

[0002] With the continuous development of aerospace technology, variable topology aerospace structures are increasingly widely used in space exploration, astronomical observation, and other fields. Variable topology aerospace structures refer to spacecraft systems whose structural form or connection relationships can be actively or passively changed during on-orbit operation, such as space solar power stations and ultra-large artificial gravity spacecraft. These structures can reach dimensions of hundreds or even thousands of meters. Due to their enormous size and complex structure, their scale far exceeds the payload limit of a single rocket launch. Therefore, "modular design and manufacturing, and on-orbit assembly" has become one of the main methods for constructing variable topology aerospace structures. Space assembly refers to the technical process of combining multiple independent modules or components into a complete functional structure according to a predetermined plan in outer space, through the operation of astronauts or space robots. During the space assembly process of variable topology aerospace structures, accurate modeling is crucial for predicting structural performance, guiding assembly operations, and ensuring structural stability.

[0003] However, traditional aerospace structure modeling methods are mostly based on overall static models, which are difficult to adapt to the problems of dynamic addition and subtraction of modules, real-time changes in connection relationships and complex environmental disturbances during space assembly. They are also difficult to meet the modeling and analysis needs of complex space assembly processes for variable topology aerospace structures. Summary of the Invention

[0004] To address the technical challenges of current aerospace structure modeling methods in meeting the modeling requirements of complex space assembly processes for variable topology aerospace structures, the present invention aims to provide an automated modeling method for the space assembly process of variable topology aerospace structures.

[0005] On one hand, embodiments of the present invention include an automated modeling method for the space assembly process of variable topology aerospace structures, the automated modeling method for the space assembly process of variable topology aerospace structures comprising:

[0006] Obtain the model database; the model database stores parameter information of multiple assembly modules of the variable topology aerospace structure;

[0007] Obtain the assembly database; the assembly database stores the assembly sequence information of each assembly module, and the assembly sequence is obtained according to intelligent planning;

[0008] Execute multiple rounds of assembly modeling process and obtain the solution results of the overall structural dynamic equations after each round of assembly modeling process;

[0009] The assembly modeling process in any round includes the following steps:

[0010] An overall structural dynamic equation is established, which includes orbital dynamic equation, attitude dynamic equation, and structural dynamic equation, and there is mutual coupling between orbit, attitude, and structure. In this round of assembly modeling process, the overall structural dynamic equation is obtained through initialization. Otherwise, the overall structural dynamic equation updated in the previous round of assembly modeling process is obtained as the overall structural dynamic equation for this round of assembly modeling process.

[0011] Based on the assembly sequence information, the parameter information of the assembly module corresponding to the assembly modeling process in this round is obtained from the model database;

[0012] The overall structural dynamic equations are updated based on the assembly sequence information and the parameter information.

[0013] Solve the updated overall structural dynamics equations.

[0014] Furthermore, the acquisition of the model database includes:

[0015] Obtain structural information of the variable topology aerospace structure to be modeled;

[0016] To obtain information on the carrying capacity of space launch vehicles;

[0017] Based on the carrying capacity information, the structural information is subjected to fractal processing to obtain parameter information of multiple assembly modules;

[0018] The parameter information of each assembly module is stored in the model database.

[0019] Further, updating the overall structural dynamic equations based on the assembly sequence information and the parameter information includes:

[0020] Based on the assembly sequence information, constraint equations are added to the overall structural dynamics equations;

[0021] Update the mass parameters in the overall structural dynamics equations based on the parameter information;

[0022] Based on the updated mass parameters, the interaction coupling calculations between the various assembly modules in the overall structure are performed, and the coupling parameters in the overall structure dynamic equations are updated based on the calculation results; wherein, the overall structure is the structure described by the overall structure dynamic equations;

[0023] Obtain space environment condition information, and update the external force parameters in the overall structural dynamic equations based on the space environment condition information.

[0024] Furthermore, solving the updated global structural dynamics equations includes:

[0025] The updated overall structural dynamics equations were solved using numerical calculation methods.

[0026] Based on the solution results, the dynamic response of the overall structure is obtained.

[0027] Furthermore, the automated modeling method for the space assembly process of the variable topology aerospace structure also includes:

[0028] The parameter information read from the model database is activated.

[0029] Furthermore, the automated modeling method for the space assembly process of the variable topology aerospace structure also includes:

[0030] The parameter information that has not been read from the model database is deactivated.

[0031] Furthermore, the multi-round assembly modeling process includes:

[0032] The total number of rounds in the assembly modeling process is determined based on the total number of assembly modules in the model database.

[0033] Establish the correspondence between each assembly module and each round of the assembly modeling process;

[0034] Based on the assembly sequence information, determine the execution order of each round of the assembly modeling process;

[0035] The assembly modeling process is executed sequentially in each round according to the execution order.

[0036] On the other hand, embodiments of the present invention also include an automated modeling system for the space assembly process of variable topology aerospace structures, the automated modeling system for the space assembly process of variable topology aerospace structures comprising:

[0037] The first module is used to acquire a model database; the model database stores parameter information of multiple assembly modules of a variable topology aerospace structure;

[0038] The second module is used to obtain the assembly database; the assembly database stores the assembly sequence information of each assembly module;

[0039] The third module is used to execute multiple rounds of assembly modeling process and obtain the solution results of the overall structural dynamic equations after each round of assembly modeling process.

[0040] The assembly modeling process in any round includes the following steps:

[0041] Establish the overall structural dynamics equation; wherein, when the assembly modeling process described in this round is the first round, the overall structural dynamics equation is obtained through initialization; otherwise, the overall structural dynamics equation updated in the previous round of assembly modeling process is obtained as the overall structural dynamics equation for the assembly modeling process described in this round.

[0042] Based on the assembly sequence information, the parameter information of the assembly module corresponding to the assembly modeling process in this round is obtained from the model database;

[0043] The overall structural dynamic equations are updated based on the assembly sequence information and the parameter information.

[0044] Solve the updated overall structural dynamics equations.

[0045] On the other hand, embodiments of the present invention also include a computer device, including a memory and a processor, the memory for storing at least one program, and the processor for loading at least one program to execute the automated modeling method for the space assembly process of variable topology aerospace structures in the embodiments.

[0046] On the other hand, embodiments of the present invention also include a computer-readable storage medium storing a processor-executable program, which, when executed by a processor, is used to perform the automated modeling method for the space assembly process of variable topology aerospace structures in the embodiments.

[0047] The beneficial effects of the embodiments of the present invention are as follows: The automated modeling method for the space assembly process of variable topology aerospace structures in the embodiments, by automatically modeling the space assembly process of variable topology aerospace structures and executing multiple assembly modeling processes to update and solve the dynamic equations of the overall structure, can establish a dynamic model, realize the automated expansion and updating of the dynamic model during the space assembly process, characterize the dynamic evolution law of the variable topology structure during the assembly process, and thus accurately simulate the space assembly process of variable topology aerospace structures. It can improve modeling efficiency and accuracy, effectively handle a large amount of data and complex assembly logic, provide strong theoretical support for the on-orbit assembly of variable topology aerospace structures, provide a theoretical basis for the dynamic evolution analysis of on-orbit assembly, and has important engineering application value. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the configuration of the multi-rotational joint space solar power station (MR-SPS) in the embodiment;

[0049] Figure 2 This is a schematic diagram of the assembly process of the multi-rotational joint space solar power station (MR-SPS) in the embodiment;

[0050] Figure 3This is a schematic diagram of the main support structure of the multi-rotational joint space solar power station (MR-SPS) in the embodiment;

[0051] Figure 4 This is a schematic diagram illustrating the steps of an automated modeling method for the space assembly process of variable topology aerospace structures in an embodiment.

[0052] Figure 5 This is a flowchart and principle diagram of the automated modeling method for the space assembly process of variable topology aerospace structures in the embodiment;

[0053] Figure 6 This is a schematic diagram of the assembly modeling process for each round in the embodiment;

[0054] Figure 7 This is a schematic diagram showing the connection relationship between the assembly modules in the overall structure of the embodiment;

[0055] Figure 8 This is a schematic diagram illustrating the principle of constraint processing in the embodiment;

[0056] Figure 9 This is a schematic diagram of the displacement curves of the space truss structure during the 6th and 12th assembly stages when the simulation verification was performed in the embodiment.

[0057] Figure 10 This is a schematic diagram of the position error variation curve during simulation verification in the embodiment;

[0058] Figure 11 This is a schematic diagram of the speed error variation curve during simulation verification in the embodiment;

[0059] Figure 12 This is a schematic diagram of the attitude angle change curve during simulation verification in the embodiment;

[0060] Figure 13 This is a schematic diagram of the attitude angular velocity change curve during simulation verification in the embodiment;

[0061] Figure 14 This is a schematic diagram of the displacement response curve of the first motor during simulation verification in the embodiment.

[0062] Figure 15 This is a schematic diagram of the displacement response curve of the second motor during simulation verification in the embodiment;

[0063] Figure 16 This is a schematic diagram of the displacement response curve of the third motor during simulation verification in the embodiment;

[0064] Figure 17 This is a schematic diagram of the displacement response curve of the fourth motor during simulation verification in the embodiment;

[0065] Figure 18This is a schematic diagram illustrating the parallel execution of each round of assembly modeling in the embodiment. Detailed Implementation

[0066] Traditional aerospace structure modeling methods are mostly based on overall static models, which are difficult to adapt to the problems of dynamic addition and subtraction of modules, real-time changes in connection relationships and complex environmental disturbances during space assembly. They are also difficult to meet the modeling requirements of complex space assembly processes for variable topology aerospace structures. Therefore, there is an urgent need for an automated modeling method to improve modeling efficiency and accuracy and ensure the smooth progress of space assembly of variable topology aerospace structures.

[0067] This embodiment provides an automated modeling method for the space assembly process of variable topology aerospace structures. Specifically, a space solar power satellite (SPS) is used as an example of a variable topology aerospace structure to illustrate the automated modeling method for the space assembly process of variable topology aerospace structures.

[0068] Space solar power stations (SPS) are a typical variable-topology space structure and an important solution for future clean energy acquisition. Traditional space solar power station designs face several technical challenges, such as the high technical difficulty of ultra-high-power conductive rotating joints in non-concentrated centralized power supply schemes, the inability of non-concentrated distributed power supply schemes to demonstrate continuous power supply advantages, and the challenges of designing high-precision concentrating systems in concentrating schemes. To simplify the technical difficulties of ultra-high-power conductive rotating joints in non-concentrated space solar power stations, the China Academy of Space Technology proposed a concept scheme for multiple rotation joint space solar power stations (MR-SPS). The core of the MR-SPS is modular design, mainly composed of a central body (central truss structure), microwave transmitting antenna, connecting trusses, and battery arrays [including solar panels and motor modules], with the following configuration: Figure 1 As shown.

[0069] Specifically, Figure 1 The Multi-Rotating Space Solar Power Station (MR-SPS) shown has a "one-line" supporting truss structure, and its assembly process is as follows: Figure 2 As shown. (Refer to...) Figure 2 The space solar power station (SPS) has a total truss structure length of 351m, with each truss assembly module being 19.5m long. The entire assembly process is carried out in 18 stages. Compared to the structure in the first assembly stage, the size of the truss structure after assembly has increased 18 times.

[0070] Figure 1 The main support structure of the multi-rotational joint space solar power station (MR-SPS) shown is as follows: Figure 3 As shown, the automated modeling method for the assembly process proposed in this paper is validated. In this embodiment, using... Figure 3 Taking the modeling and simulation of the assembly process of the main support structure of the multi-rotational-joint space solar power station (MR-SPS) as an example, this paper illustrates the automated modeling method for the space assembly process of variable topology aerospace structures. The finite element modeling and numerical simulation steps used in the modeling process can all be implemented using custom-written programs in MATLAB.

[0071] Reference Figure 4 The automated modeling method for the space assembly process of variable topology aerospace structures includes the following steps:

[0072] S1. Obtain the model database;

[0073] S2. Obtain the assembly database;

[0074] S3. Execute multiple rounds of assembly modeling process and obtain the solution results of the overall structural dynamic equations after each round of assembly modeling process.

[0075] Each round of assembly modeling process includes the following steps:

[0076] S301. Establish the overall structural dynamics equation; wherein, when the current assembly modeling process is the first round, the overall structural dynamics equation is obtained through initialization; otherwise, the overall structural dynamics equation updated in the previous round of assembly modeling process is obtained as the overall structural dynamics equation for the current round of assembly modeling process.

[0077] S302. Based on the assembly sequence information, obtain the parameter information of the assembly module corresponding to this round of assembly modeling process from the model database;

[0078] S303. Update the overall structural dynamic equations based on the assembly sequence information and parameter information;

[0079] S304. Solve the updated global structural dynamics equations.

[0080] Figure 4 The process and principle of automated modeling methods for the space assembly process of variable topology aerospace structures are as follows: Figure 5 As shown.

[0081] Reference Figure 4 and Figure 5 In step S1, the structural information of the variable topology space structure to be modeled [i.e., multi-rotational joint space solar power station (MR-SPS)] is obtained, that is... Figure 2 and Figure 3The structural information is shown; next, the carrying capacity information of the space launch vehicle is obtained, specifically including the envelope size and carrying capacity of the launch vehicle used to transport the Multi-Rotating Joint Space Solar Power Station (MR-SPS). The carrying capacity information indicates the size of the object that the space launch vehicle can carry at one time, forming a constraint on the MR-SPS. If the MR-SPS exceeds the range of the carrying capacity information, then the MR-SPS needs to be disassembled into multiple independent and assembleable modules, i.e., assembly modules.

[0082] In this embodiment, based on the constraints of the space launch vehicle's carrying capacity information, the main support structure of the multi-rotating joint space solar power station (MR-SPS) is subjected to fractal processing, thereby disassembling it into assembly modules such as the central body, connecting trusses, and motor modules. For Figure 3 The main support structure of the multi-rotational joint space solar power station (MR-SPS) shown has the same number of connecting trusses and motor modules obtained by fractal processing (e.g., N connecting trusses and N motor modules).

[0083] In this embodiment, for each assembly module, its mass parameters (such as the mass and center of mass of the motor module), material properties (such as the elastic modulus, Poisson's ratio, and density of the material used in the truss module), and geometric dimensional information are obtained through measurement and material performance testing. Assembly modules of the same type can have the same geometric and material parameter configurations. In step S1, the obtained parameter information of these assembly modules is stored in the model database. Some of the parameter information stored in the model database is shown in Table 2.

[0084] Table 2 shows the parameter information of the assembly modules stored in the model database.

[0085]

[0086] In step S2, assembly sequence information is generated based on the assembly order of each assembly module in the model database. For example, for Figure 3The main support structure of the Multi-Rotating Joint Space Solar Power Station (MR-SPS) shown can be assembled using a symmetrical assembly sequence, where connecting trusses and motor modules are assembled on both sides of the power station at different times. Therefore, with N connecting trusses and N motor modules, the entire assembly process can be divided into N stages. In the first stage, a set of connecting trusses and motor modules is installed on the foundation of the central body to form the overall structure. Then, in the second stage, a new set of connecting trusses and motor modules is installed on the overall structure of the first stage to form a new overall structure, and so on, achieving an assembly cycle of "connecting truss-motor module". The assembly sequence information records the module number, position, and connection relationships with other modules to be installed in each stage of the assembly process, saved in a time-series format, and stored in the assembly database.

[0087] The principle behind step S2 is that the geometric configuration of the space structure gradually changes as modules are assembled throughout the on-orbit assembly phase. A reasonable assembly sequence is planned to reduce structural vibration and attitude changes during assembly. Taking into account the on-orbit state of the space structure (position, attitude, etc.), inherent structural properties (such as fundamental frequency), the motion trajectory of the assembly robot / manipulator, and fuel consumption, an optimization algorithm is used to rationally plan the assembly sequence, clarifying the order of each module during space assembly. Each module is assigned a unique number, its initial position in the overall structure is determined, and the connection relationships between modules, including connection methods and positions, are recorded. The number, position, connection relationships, and assembly sequence of each module are determined, and this data is stored in the assembly database. Through the establishment of the model database and the assembly database, systematic management of information on each module of the variable topology space structure is achieved.

[0088] In this embodiment, refer to Figure 6 When it is determined from the assembly sequence information that multiple assembly stages with sequential relationships need to be executed, such as stage 1, stage 2, ... stage N, when executing step S3, N rounds of assembly modeling process can be executed. Each round of assembly modeling process corresponds to an assembly stage, thereby simulating this assembly stage.

[0089] In this embodiment, the following steps are described using one round of assembly modeling process (the i-th round of assembly modeling process) as an example:

[0090] S301. Establish the overall structural dynamics equations;

[0091] S302. Based on the assembly sequence information, obtain the parameter information of the assembly module corresponding to this round of assembly modeling process from the model database;

[0092] S303. Update the overall structural dynamic equations based on the assembly sequence information and parameter information;

[0093] S304. Solve the updated global structural dynamics equations.

[0094] In this embodiment, the overall structural dynamic equation is the dynamic equation describing the overall structure. The overall structure refers to the structure assembled in the first (stage 1), second (stage 2), ..., (stage i-1)th rounds of assembly modeling (stage i-1) that have already been executed. For example, when i = 1, the overall structure refers to... Figure 3 The central body in the model; when i=2, the overall structure refers to the central body plus the assembly modules (connecting truss and motor modules) assembled on the central body in the first round of assembly modeling process (corresponding to stage 1) to form the whole.

[0095] In this embodiment, for Figure 3 The overall structural dynamic equations of the main support structure of the multi-rotational joint space solar power station (MR-SPS) shown can be derived through the following process:

[0096] A dynamic model of the overall structure was established using finite element analysis and the first-order Lagrange method. Considering the connection relationship of the truss modules, appropriate element types and mesh generation parameters were set to accurately simulate the mass distribution and stiffness characteristics of the structure. Factors such as microgravity in the space environment were added to the model as load conditions.

[0097] a. Calculate kinetic energy and potential energy

[0098] First, calculate the kinetic and potential energy of the overall structure. The kinetic energy mainly includes the kinetic energy of the central body, the kinetic energy of the connecting trusses, the kinetic energy of the motor modules, and the strain energy of the connecting trusses.

[0099] ① Kinetic energy of the central rigid body

[0100] Any mass element dm on the central body b The position vector is represented as

[0101]

[0102] Where r b For the mass element dm in the body coordinate system b Relative centroid R c Position vector, C be This is the coordinate transformation matrix from the inertial coordinate system to the body coordinate system.

[0103] Differentiating the position vector yields

[0104]

[0105] Where ω is the angular velocity vector of the body at the center of the body coordinate system relative to the inertial coordinate system.

[0106] The kinetic energy of the central rigid body is expressed as

[0107]

[0108] Where m b For the central body mass, J b Let be the rotational inertia matrix of the central body.

[0109] ② Connecting the kinetic and potential energy of the truss

[0110] The connecting truss modules are discretized using Euler-Bernoulli beam elements. The generalized coordinates of the i-th node of the n-th truss module are defined as follows:

[0111]

[0112] Among them, u n,i Let α be the displacement vector of node i along each direction of the assembly module coordinate system. n,i Let be the rotation vector of the cross section at node i around the three coordinate axes.

[0113] The generalized coordinates of the nth truss module node are

[0114]

[0115] Any mass element dm on the nth truss module n,t The position vector is represented as

[0116]

[0117] Where, r n,t u is the position vector of the mass element relative to the connection point when no deformation occurs. n,t The position vector, which is the position vector relative to the undeformed state, can be obtained through calculation using finite element theory.

[0118] Differentiating the position vector yields

[0119]

[0120] The kinetic energy of the nth truss module is expressed as:

[0121]

[0122] Where m n,t For the mass of the connecting truss.

[0123] The potential energy of the nth truss module is expressed as:

[0124]

[0125] Where K t Here is the stiffness matrix of the truss module.

[0126] ③ Motor module kinetic energy

[0127] Define the generalized coordinates of the nth motor module as follows:

[0128] q n,s =[u n,s v n,s w n,s ] T (10)

[0129] The position vector of the centroid of the nth motor module in the inertial coordinate system is:

[0130]

[0131] Differentiating the position vector yields

[0132]

[0133] The kinetic energy of the motor module can be expressed as

[0134]

[0135] Where m n,s For the quality of the motor module.

[0136] The kinetic energy of the overall structure is expressed as

[0137]

[0138] The potential energy of the overall structure is expressed as

[0139]

[0140] The Lagrangian function of the overall structure is expressed as:

[0141] L = TV (16)

[0142] b. Constraint Handling

[0143] During assembly, the constraints between modules consist of two parts: geometric constraints and boundary condition constraints. The connection diagram is as follows: Figure 7 As shown.

[0144] Here, constraint equations are used to characterize the connection relationships between the modules. The constraint equations are expressed as follows:

[0145]

[0146] c. Dynamic equations

[0147] Define generalized coordinates as

[0148]

[0149] The first kind of Lagrange equation is expressed as:

[0150]

[0151] Substituting equations (16) and (17) into the equations, we can obtain...

[0152]

[0153] Where, m a Let J be the mass of the overall structure, J be the moment of inertia of the structure, and M be the mass of the structure. t Let C be the mass matrix of the truss module. t Here is the damping matrix of the truss module, F and M are the resultant external forces and moments acting on the structure, respectively, and f n,s f n,t These represent the external forces acting on the motor module, the external forces acting on the truss module, and the net external force S. oa S oq,n,s S oq,n,t S aq,n,s S aq,n,t These are the corresponding coupling coefficient matrices.

[0154] Therefore, equations (20)-(23) constitute the overall structural dynamics equations to be established in step S301, where equation (20) represents the orbital motion equation, equation (21) represents the overall structural attitude dynamics model, equation (22) represents the motor module motion equation, and equation (23) represents the truss module vibration equation. The overall structural dynamics equations composed of equations (20)-(23) establish a dynamic model that includes the overall mechanical properties of the structure, including orbital dynamics, attitude dynamics, and structural dynamics, reflecting the design requirements and structural characteristics of variable topology aerospace structures. This equation comprehensively considers the influence of the structure's mass distribution, stiffness characteristics, damping characteristics, and external space environment factors on the structural dynamics behavior, providing a basic framework for subsequent assembly process modeling and a foundation for dynamic modeling during the assembly process. The dynamics equations can be gradually updated as assembly progresses.

[0155] In this embodiment, when executing step S3, the parameter information that has been read in the model database is activated. That is, the overall structural dynamics equation established in step S301 considers the parameter information that has been read. For example, when executing the i-th round of assembly modeling, the overall structural dynamics equation established in step S301 considers the parameter information that has been read in the 1st round of assembly modeling, the 2nd round of assembly modeling, ..., the (i-1)th round of assembly modeling. On the other hand, the parameter information that has not been read in the model database is deactivated. That is, the overall structural dynamics equation established in step S301 does not consider the parameter information that has not been read (equivalent to the parameter information that has not been read being invalid in the overall structural dynamics equation). For example, when executing the i-th round of assembly modeling, the parameter information that is read in the (i+1)th round of assembly modeling, the (i+2)th round of assembly modeling, ..., the Nth round of assembly modeling is not considered.

[0156] By deactivating unread parameter information, the amount of data that needs to be processed can be reduced, which helps to speed up the execution of each round of assembly modeling and reduce the demand for computing resources.

[0157] The dynamic characteristics of variable topology aerospace structures are analyzed from the perspective of structural dynamics. Assuming that during assembly, other influencing factors such as the connection gaps between assembly modules are not considered, only the truss structure before and after assembly is considered, and that the truss assembly modules are rigidly locked to the assembled parts immediately after assembly, forming an integral structure. Using rod elements as the basic units of the truss structure, and considering only the influence of structural dynamics, the structural dynamic equations of the overall space truss are derived based on (23):

[0158]

[0159] Among them, M t C t K t Let q represent the mass matrix, damping matrix, and stiffness matrix of the entire space truss structure, respectively, where the damping is Rayleigh damping; t Represents the displacement vector of a node; u t and w t L represents the control and disturbance forces, respectively. tu and L tw These represent the position matrices of the control force and the disturbance force, respectively.

[0160] according to Figure 2 The assembly process shown proceeds step by step, updating the "activated" structural dynamics parameters. In the Nth assembly stage, the structural dynamics equations of the space truss structure are as follows:

[0161]

[0162] The dynamic response of variable topology aerospace structures is analyzed from the perspective of orbital, attitude, and structural coupling dynamics. Therefore, for the currently executed i-th round of assembly modeling process, if i=1, that is, if the current execution is the first round of assembly modeling process, then since there is only the central body assembly module at present, and no parameter information of any truss module, motor module, or other assembly modules has been read, that is, at this time, the overall structural dynamic equation in step 301 only retains the mechanical properties and other parameter information of the basic central body for model calculation, and the parameter information related to the truss module, motor module, and other assembly modules in the overall structural dynamic equation is set to invalid. At this time, the overall structural dynamic equation shown in equations (20)-(23) can be simplified to

[0163]

[0164] Equations (26) and (27) represent orbital motion and attitude motion, respectively, which can be simply represented as rigid body motion.

[0165] In step S302, based on the assembly sequence information, the i-th round of assembly modeling process corresponds to stage i, and the parameter information of the assembly module to be installed in stage i is obtained from the model database.

[0166] In step S303, the parameter information obtained in step S302 is activated and used to update the overall structural dynamic equations. The process of updating the overall structural dynamic equations using the parameter information specifically includes four steps: constraint handling, parameter updating, coupling calculation, and external disturbance loading.

[0167] a. Constraint Handling: Assuming that the assembly module to be assembled into the overall structure in the i-th round of assembly modeling (corresponding to stage i) is rigidly connected to the assembly modules already included in the overall structure, based on the connection relationships between the assembly modules represented by the assembly sequence information in the assembly database, the corresponding constraints are accurately applied in the model to ensure the correct position and orientation during the assembly process; specifically, it can be as follows: Figure 8 As shown, different assembly modules are constrained by means of "nodal degree of freedom loading" and "constraint equation connection". For example, for the connection of truss modules, the relative displacement and rotation between truss modules are restricted to ensure that the connection method of the modules in the model is consistent with the actual assembly situation. By performing the above operations, the dynamic equation of the corresponding module is activated, and the constraint equation of the assembly module to be assembled in the i-th round of assembly modeling process (corresponding to stage i) is introduced into the overall structural dynamic equation before the update.

[0168] b. Parameter Update: As assembly progresses and new assembly modules are added, the overall structural mass parameters (m) will change. aSince the parameters of J) change abruptly, the mass parameters in the overall structural dynamic equation are updated according to the parameter information of the assembly module to be assembled in the i-th round of assembly modeling process (corresponding to stage i). Similarly, the material properties and other information of the new assembly module can be extracted from the model database and integrated into the overall structural dynamic equation. At the same time, the rotational inertia and stiffness matrix and other parameters in the overall structural dynamic equation are updated according to the actual assembly position and connection state of the new assembly module, so that the updated overall structural dynamic equation model can accurately reflect the mechanical characteristics of the structure in the current assembly state.

[0169] c. Coupling Calculation: Based on the updates of parameters a and c, the interaction coupling calculation of the structure is performed. Specifically, considering the influence of the interactions between assembly modules and the orbit-attitude-structure interactions on the dynamic behavior of the overall structure after the addition of assembly modules in the i-th round of assembly modeling (corresponding to stage i), the S in the overall structural dynamic equation is calculated. oa S oq,n,s S oq,n,t S aq,n,s S aq,n,t C o C a C n,t C n,s The coupling parameter matrix is ​​updated.

[0170] d. External disturbance loading: Based on the actual space environment conditions (such as gravity gradient, space radiation, etc.), apply corresponding external disturbance loads to the overall structural dynamic equations, such as assembly contact collision force, solar radiation pressure, etc. For example, for equation (20) (orbit equation) in the overall structural dynamic equations, increase the gravity of the assembly module to the resultant external force F; for equation (21) (attitude equation) in the overall structural dynamic equations, change the gravity gradient torque in the resultant external torque M; for equations (22) (motor module vibration equation) and (23) (truss module vibration equation) in the overall structural dynamic equations, change f according to the contact collision force. n,s f n,t .

[0171] By executing the above process ad, step S303 is completed, and the overall structural dynamic equations are updated. Next, step S304 is executed, and the updated overall structural dynamic equations are solved by numerical calculation, thereby obtaining the dynamic responses of the overall structure, such as displacement, velocity, and acceleration, under the current assembly state, and analyzing the stability and mechanical properties of the structure.

[0172] Reference Figure 1 or Figure 2After executing steps S301-S304 in the i-th round of assembly modeling (corresponding to stage i), if i < N, it indicates that the entire assembly modeling process has not yet been completed. In this case, steps S301-S304 in the (i+1)-th round of assembly modeling (corresponding to stage i+1) are executed. Specifically, when executing step S301 in the (i+1)-th round of assembly modeling, the updated overall structural dynamics equations from step S303 in the i-th round of assembly modeling can be obtained. This process is repeated until all N rounds of assembly modeling are completed, thus achieving automated modeling in the spatial assembly process.

[0173] In summary, the automated modeling method for the space assembly process of variable topology aerospace structures in this embodiment has the following technical effects:

[0174] 1. Improved modeling efficiency: Through automated processes, the repetitive and tedious dynamic modeling work at different assembly stages is avoided. It can quickly complete the modeling of the space assembly process of variable topology aerospace structures, greatly improving modeling efficiency and meeting the requirements for modeling speed in engineering practice.

[0175] 2. Accurate description of the assembly process: Based on detailed structural fractals and database establishment, this method can accurately record and process the information of each module of the variable topology aerospace structure. In addition, it performs precise constraint processing, parameter updates and coupling calculations during the "activation" of modules, and fully considers various factors in the structural assembly process as well as the influence of the external space environment, so that the model can more realistically reflect the actual situation of the space assembly process of the variable topology aerospace structure.

[0176] 3. Optimize assembly schemes: By automating the assembly process of variable topology aerospace structures, different assembly sequences and external environmental conditions can be simulated in the model. The dynamic response and performance of the structure under various conditions can be analyzed, providing strong theoretical support for optimizing assembly schemes and helping to improve the success rate of space assembly of variable topology aerospace structures and the stability of the structures.

[0177] 4. Reduce costs and risks: Accurate and efficient modeling can identify potential problems in the space assembly process of variable topology aerospace structures in advance, avoiding design defects and safety hazards during actual assembly, thereby reducing R&D costs and engineering risks, and improving the economic benefits and reliability of aerospace engineering.

[0178] Simulation verification

[0179] Efficiency analysis of automated modeling during the assembly process was conducted. In the simulation, the structural dynamics modeling in the automated modeling method for the space assembly process of the variable topology aerospace structure in this embodiment was numerically simulated and compared with the dynamic model established using the traditional finite element method. Here, the traditional modeling method refers to remodeling the already assembled overall structure after each new assembly module is assembled. The specific process of model building in both methods starts from the rod element, including the establishment of the structural dynamics model of the assembled parts at each assembly stage, until the establishment of the overall structural model at the final assembly stage. In this study, the model building and updating were implemented using a self-written program in MATLAB.

[0180] The structural dynamics models of the space truss at each assembly stage were established using the automated modeling method for the variable topology aerospace structure space assembly process in this embodiment, and numerical simulations were performed. The response curves of the truss structure at assembly stages 6 and 12 are shown below. Figure 9 As shown. After the sixth truss substructure is assembled, the length of the space truss structure is 117m. Assuming the driving force at the end node is 0.5N, the corresponding structural response is as follows. Figure 9 As shown in part (a); after the 12th truss substructure is assembled, the length of the space truss structure is 234m. Assuming the driving force at the end node is 0.05N, the corresponding structural response is as follows: Figure 9 As shown in part (b) of the document.

[0181] The advantages of automated modeling will be discussed below in terms of efficiency improvement, model scalability, functional scalability, automation level, and modeling continuity. Table 2 shows that, compared with traditional modeling methods, the automated modeling method for the variable topology aerospace structure space assembly process in this embodiment reduces the modeling time from 564.084s to 145.93s when establishing the dynamic model of the truss structure with 18 assembly stages, improving efficiency by approximately 74.13%. It should be noted that the space truss structure involved in this simulation only covers 18 substructures. If the overall structure contains hundreds or thousands of substructures, the advantage of this method in assembly modeling efficiency will become even more prominent. This efficiency improvement is due to the scalability of the proposed method. Using this method, the overall structural model is pre-built, and then only the corresponding structural model needs to be "activated" at each assembly stage, simplifying the modeling process and avoiding repetitive modeling work. In contrast, traditional methods require remodeling the assembled part of the overall structure or modeling the new type of substructure to be assembled before integration, which increases workload and complexity.

[0182] Furthermore, the automated modeling method for the space assembly process of variable topology aerospace structures in this embodiment also demonstrates advantages in terms of functional scalability. By pre-considering the relationship between the model of the substructure to be assembled and the model of the assembled parts, it facilitates the subsequent expansion and update design of the structure controller during the on-orbit assembly phase. Throughout the assembly phase, the dynamic modeling is coherent, reducing manual intervention and improving the degree of automation. In contrast, traditional modeling methods require manual analysis of new or new types of assembled substructures multiple times when establishing the structural dynamic model for the next assembly phase, which affects the continuity of modeling. Therefore, the proposed method not only improves the efficiency of dynamic modeling during the space assembly phase but also enhances the scalability and functional extensibility of the model, while ensuring the continuity and automation of the modeling process.

[0183] Table 2 Comparative Analysis of Automated Modeling Methods

[0184]

[0185]

[0186] To address the problem of coupled dynamics modeling during the on-orbit assembly of variable topology aerospace structures, this paper presents an automated modeling method for the space assembly process of variable topology aerospace structures. Simulation verification of the dynamics and control during the space assembly process of the MR-SPS main support structure is conducted. The establishment and updating of the dynamic model in this study are implemented by a self-written program in MATLAB.

[0187] Assume the initial attitude angle of the main structure is α = [3°, 2°, -1°]. T The attitude angular velocity is The time interval between two adjacent assembly operations is t. ass =50s, and a sliding mode controller is used to achieve stable control. For example Figures 10-17 The curves for position error, velocity error, attitude angle, attitude angular velocity, and displacement response of the four motor modules are displayed respectively.

[0188] Figure 10 and Figure 11 The position and velocity error curves shown reflect the change in the deviation between the actual position and the desired commanded position of the central body over time. The curves indicate that the assembly process meets the stringent requirements for precise positioning. However, slight fluctuations occur in the velocity error curve during each assembly step, due to track-structure coupling. Effective suppression of velocity error is crucial for ensuring smooth movement and reducing impact, especially in precision docking operations.

[0189] Figure 12 , Figure 13The diagram shows the attitude angle and angular velocity changes of the central body during assembly. Initially exhibiting attitude deviations, active control quickly reduced these deviations to within ±0.1°, maintaining high-precision attitude stability throughout the assembly process. Stable attitude is a prerequisite for ensuring accurate positioning and avoiding collisions during assembly.

[0190] Figure 14 , Figure 15 , Figure 16 and Figure 17 The displacement response curves of the first through fourth motor modules during the assembly process are shown. As key moving components connecting the satellite body to the large solar array, the dynamic characteristics of the motors directly affect the overall satellite stiffness and pointing accuracy. The displacement response curves of all four motor modules show vibration characteristics synchronized with the assembly process. Comparing the responses of the four modules, some differences can be observed in vibration amplitude, frequency, and decay time. This difference likely stems primarily from the different positions of the motor modules and the varying coupling effects they experience. This results in the fourth module having a relatively large structural amplitude, but under the constraint of the connecting truss module, it quickly decays and tends to a new equilibrium position, without exhibiting sustained divergence or constant-amplitude oscillations.

[0191] Based on the proposed automated modeling method for the spatial assembly process, we conducted assembly dynamics modeling and control simulation verification of the MR-SPS main support structure, which helps to reveal the dynamic evolution law during the assembly process.

[0192] In this embodiment, during the execution of all N rounds of assembly modeling process, in addition to... Figure 6 The diagram shows the assembly modeling process executed sequentially in a serial manner. Alternatively, it can be implemented using... Figure 18 The parallel format shown. (Refer to...) Figure 18 The entire N-round assembly modeling process can be divided into multiple process groups. The rounds of assembly modeling within the same process group have a sequential execution order. For example, process group 1 includes consecutive rounds of assembly modeling, such as round 1, round 2, ..., round L. Furthermore, the number of rounds in the assembly modeling processes within different process groups decreases sequentially according to the execution order. Figure 18 The algorithm can be configured such that L > ML > LN, meaning that process group 1 contains the most rounds of assembly modeling (L), process group 2 contains a medium number of rounds of assembly modeling (ML), and process group 3 contains the fewest rounds of assembly modeling (LN). After this partitioning, with sufficient computing resources, process groups 1, 2, and 3 can be executed in parallel. Within the same process group, each round of assembly modeling is executed sequentially; for example, in process group 1, the first round of assembly modeling, the second round, and so on, up to the Lth round, are executed sequentially.

[0193] Figure 18 In this process, process group 1 is equivalent to simulating and modeling stage 1, stage 2... stage L, process group 2 is equivalent to simulating and modeling stage L+1, stage 2... stage M, and process group 3 is equivalent to simulating and modeling stage M+1, stage 2... stage N. Parallel execution can improve the modeling speed.

[0194] After the parallel execution of process group 1, process group 2 and process group 3, the execution results of each process group 1, process group 2 and process group 3 can be serially executed multiple times to obtain the final result.

[0195] For example, the execution result of process group 1 (updating the obtained overall structural dynamic equation) can be used as the initial overall structural dynamic equation obtained in the first round of assembly modeling, and the execution result of process group 2 can be used as the assembly module that needs to be assembled into the overall structure in the first round of assembly modeling, and the first round of assembly modeling can be executed; then, the execution result of process group 3 can be used as the assembly module that needs to be assembled into the overall structure in the third round of assembly modeling, and the second round of assembly modeling can be executed.

[0196] because Figure 6 The serial execution process shown is closer to the actual assembly process of variable topology aerospace structures, while Figure 18 Parallel execution processes can cause deviations from serial execution processes. By setting the number of rounds of assembly modeling processes in different process groups to decrease sequentially in the direction of execution order, it is possible to simulate the process of the overall structure of the variable topology aerospace structure increasing sequentially relative to the newly added assembly modules in the actual assembly process while achieving parallel execution. This reduces the deviation from the serial execution process and achieves a balance between modeling speed and modeling accuracy.

[0197] An automated modeling system for the space assembly process of variable topology aerospace structures can be run to execute the automated modeling method for the space assembly process of variable topology aerospace structures. Specifically, step S1 is executed by the first module of the automated modeling system, step S2 by the second module, and step S3 by the third module, thereby achieving the same technical effect as the automated modeling method for the space assembly process of variable topology aerospace structures.

[0198] A computer program can be written to execute the automated modeling method for the space assembly process of the variable topology aerospace structure in this embodiment. The computer program can be written into a computer device or storage medium. When the computer program is read out and run, the automated modeling method for the space assembly process of the variable topology aerospace structure in this embodiment can be executed, thereby achieving the same technical effect as the automated modeling method for the space assembly process of the variable topology aerospace structure in this embodiment.

[0199] It should be noted that, unless otherwise specified, when a feature is referred to as "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or indirectly fixed or connected to the other feature. Furthermore, the descriptions of "upper," "lower," "left," and "right" used in this disclosure are only relative to the relative positional relationships of the components of this disclosure in the accompanying drawings. The singular forms "a," "an," and "the" used in this disclosure are also intended to include the plural forms, unless the context clearly indicates otherwise. Moreover, unless otherwise defined, all technical and scientific terms used in this embodiment have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this embodiment specification is only for describing specific embodiments and is not intended to limit the embodiments of the invention. The term "and / or" as used in this embodiment includes any combination of one or more of the associated listed items.

[0200] It should be understood that although the terms first, second, third, etc., may be used to describe various elements in this disclosure, these elements should not be limited to these terms. These terms are only used to distinguish elements of the same type from each other. For example, a first element may also be referred to as a second element without departing from the scope of this disclosure, and similarly, a second element may also be referred to as a first element. The use of any and all instances or exemplary language (“e.g.,” “such as,” etc.) provided in this embodiment is intended only to better illustrate embodiments of the invention and, unless otherwise required, does not impose a limitation on the scope of embodiments of the invention.

[0201] It should be recognized that embodiments of the present invention can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable storage medium. The method can be implemented using standard programming techniques—including a non-transitory computer-readable storage medium configured with a computer program, wherein such a storage medium causes the computer to operate in a specific and predefined manner—according to the methods and drawings described in the specific embodiments. Each program can be implemented in a high-level procedural or object-oriented programming language to communicate with the computer system. However, if desired, the program can be implemented in assembly or machine language. In any case, the language can be a compiled or interpreted language. Furthermore, for this purpose, the program can run on a programmed application-specific integrated circuit (ASIC).

[0202] Furthermore, the procedures described in this embodiment can be performed in any suitable order, unless otherwise indicated by this embodiment or otherwise obviously contradictory to the context. The procedures (or variations and / or combinations thereof) described in this embodiment can be executed under the control of one or more computer systems configured with executable instructions, and can be implemented by hardware or a combination thereof as code (e.g., executable instructions, one or more computer programs, or one or more applications) that commonly executes on one or more processors. A computer program includes multiple instructions executable by one or more processors.

[0203] Furthermore, the method can be implemented in any suitable type of computing platform, including but not limited to personal computers, minicomputers, mainframes, workstations, networked or distributed computing environments, standalone or integrated computer platforms, or in communication with charged particle tools or other imaging devices, etc. Aspects of embodiments of the invention can be implemented as machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, optical read and / or write storage medium, RAM, ROM, etc., such that it is readable by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the processes described herein. Furthermore, the machine-readable code, or portions thereof, can be transmitted via wired or wireless networks. The invention of this embodiment includes these and other different types of non-transitory computer-readable storage media when such media comprises instructions or programs that implement the steps above in conjunction with a microprocessor or other data processor. Embodiments of the invention also include the computer itself when programmed according to the methods and techniques of embodiments of the invention.

[0204] A computer program can be applied to input data to perform the functions of this embodiment, thereby transforming the input data to generate output data stored in non-volatile memory. The output information can also be applied to one or more output devices, such as a display. In a preferred embodiment of the invention, the transformed data represents physical and tangible objects, including a specific visual depiction of physical and tangible objects generated on the display.

[0205] The above are merely preferred embodiments of the present invention. The embodiments of the present invention are not limited to the above-described implementations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the embodiments of the present invention, as long as they achieve the same technical effects, should be included within the scope of protection of the embodiments of the present invention. Within the scope of protection of the embodiments of the present invention, the technical solutions and / or implementation methods can have various modifications and variations.

Claims

1. An automated modeling method for the space assembly process of variable topology aerospace structures, characterized in that, The automated modeling method for the space assembly process of the variable topology aerospace structure includes: Obtain the model database; the model database stores parameter information of multiple assembly modules of the variable topology aerospace structure; Obtain the assembly database; the assembly database stores the assembly sequence information of each assembly module; Execute multiple rounds of assembly modeling process and obtain the solution results of the overall structural dynamic equations after each round of assembly modeling process; The assembly modeling process in any round includes the following steps: Establish the overall structural dynamics equation; wherein, when the assembly modeling process described in this round is the first round, the overall structural dynamics equation is obtained through initialization; otherwise, the overall structural dynamics equation updated in the previous round of assembly modeling process is obtained as the overall structural dynamics equation for the assembly modeling process described in this round. Based on the assembly sequence information, the parameter information of the assembly module corresponding to the assembly modeling process in this round is obtained from the model database; The overall structural dynamic equations are updated based on the assembly sequence information and the parameter information. Solve the updated overall structural dynamics equations.

2. The automated modeling method for the space assembly process of variable topology aerospace structures according to claim 1, characterized in that, The acquisition of the model database includes: Obtain structural information of the variable topology aerospace structure to be modeled; To obtain information on the carrying capacity of space launch vehicles; Based on the carrying capacity information, the structural information is subjected to fractal processing to obtain parameter information of multiple assembly modules; The parameter information of each assembly module is stored in the model database.

3. The automated modeling method for the space assembly process of variable topology aerospace structures according to claim 1, characterized in that, The step of updating the overall structural dynamic equations based on the assembly sequence information and the parameter information includes: Based on the assembly sequence information, constraint equations are added to the overall structural dynamics equations; Update the mass parameters in the overall structural dynamics equations based on the parameter information; Based on the updated mass parameters, the interaction coupling calculations between the various assembly modules in the overall structure are performed, and the coupling parameters in the overall structure dynamic equations are updated based on the calculation results; wherein, the overall structure is the structure described by the overall structure dynamic equations; Obtain space environment condition information, and update the external force parameters in the overall structural dynamic equations based on the space environment condition information.

4. The automated modeling method for the space assembly process of variable topology aerospace structures according to claim 3, characterized in that, Solving the updated global structural dynamics equations includes: The updated overall structural dynamics equations were solved using numerical calculation methods. Based on the solution results, the dynamic response of the overall structure is obtained.

5. The automated modeling method for the space assembly process of variable topology aerospace structures according to claim 1, characterized in that, The automated modeling method for the space assembly process of variable topology aerospace structures also includes: The parameter information read from the model database is activated.

6. The automated modeling method for the space assembly process of variable topology aerospace structures according to claim 1, characterized in that, The automated modeling method for the space assembly process of variable topology aerospace structures also includes: The parameter information that has not been read from the model database is deactivated.

7. The automated modeling method for the space assembly process of variable topology aerospace structures according to any one of claims 1-6, characterized in that, The multi-round assembly modeling process includes: The total number of rounds in the assembly modeling process is determined based on the total number of assembly modules in the model database. Establish the correspondence between each assembly module and each round of the assembly modeling process; Based on the assembly sequence information, determine the execution order of each round of the assembly modeling process; The assembly modeling process is executed sequentially in each round according to the execution order.

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