Dynamic modeling method for multistage energy absorption buffer system of spacecraft
By using a dynamic modeling method for a spacecraft's multi-stage energy absorption buffer system, the problem of obtaining the impact load spectrum under different landing scenarios was solved, enabling refined modeling and effective impact load assessment, and supporting the fatigue life and reuse assessment of the spacecraft.
Patent Information
- Application Number
- CN202511472932.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-15
- Publication Date
- 2026-01-23
AI Technical Summary
Existing technologies make it difficult to accurately obtain the impact load spectrum of spacecraft under different landing scenarios, which leads to difficulties in assessing the fatigue life and reuse of spacecraft.
A dynamic modeling method for a spacecraft's multi-stage energy absorption buffer system is adopted, which includes establishing a combination of parametric geometric model, dynamic model, damping element experiment, and overall dynamic model. The influence of key factors is obtained through simulation analysis to ensure the effectiveness and accuracy of the model.
It enables refined modeling of multi-stage energy absorption buffer systems for spacecraft, accurately obtains the impact load spectrum, supports fatigue life and reuse assessment of spacecraft, and ensures the stability and safety of spacecraft landing.
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Figure CN121389449A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of multistage energy-absorbing landing cushioning of spacecraft, and particularly relates to a multistage energy-absorbing cushioning dynamics modeling analysis of spacecraft, which solves the problems of nonlinear dynamics modeling of a landing energy-absorbing cushioning system of a spacecraft rod frame and verification of effective ground tests, and theoretically supports the research and development of the landing energy-absorbing cushioning system of the spacecraft rod frame through dynamics modeling analysis, rapid iterative optimization and energy-absorbing evaluation. BACKGROUND
[0002] A spacecraft lands on a planet surface to carry out interstellar exploration or reuse takeoff, and a multistage energy-absorbing cushioning system of the spacecraft realizes stable landing of the spacecraft by using internal energy-consuming component structures. The landing process is affected by many external environments, such as local wind load, air resistance, ground friction resistance, three-direction velocity, angular velocity and attitude during landing, etc., which makes the spacecraft appear in many landing situations such as single leg, two legs and four legs during the landing process. The load bearing generated when the spacecraft lands on the planet surface is very different for each of the above landing situations, and it is necessary to accurately obtain the load spectrum of the landing process in order to effectively evaluate the fatigue life and reuse of key components of the spacecraft.
[0003] To solve the problem of effective acquisition of impact load involved in the fatigue life and reuse evaluation of the spacecraft, it is necessary to carry out fine modeling of the multistage energy-absorbing cushioning system of the spacecraft. SUMMARY
[0004] The present application aims to provide a dynamics modeling method of a multistage energy-absorbing cushioning system of a spacecraft, which provides method support and theoretical guidance for nonlinear dynamics modeling of a landing cushioning system of a spacecraft rod frame and effective ground tests, solves the problem of fine modeling of the multistage energy-absorbing cushioning system of the spacecraft, ensures the effective acquisition of impact load involved in the fatigue life and reuse evaluation of the spacecraft, and supports the engineering implementation of the landing cushioning system of the spacecraft rod frame. The method steps include:
[0005] Step 1: Establish a geometric model of the structure of the multistage energy-absorbing cushioning system of the spacecraft, and parameterize the pre-attention variables in the structure design parameters; according to the working principle of the structure of the multistage energy-absorbing cushioning system of the spacecraft, establish equivalent models of connection parameters, constraint parameters, motion parameters and force elements, and parameterize the pre-attention design parameter variables;
[0006] Step 2: Based on the parameterized geometric model and parameterized mathematical equivalent model established in step 1, establish a parameterized dynamics model of the multistage energy-absorbing cushioning system of the damping element;
[0007] Step three: based on the kinetic model established in step two, all design variables that affect the buffering performance of the damping element energy-absorbing buffering parameters are analyzed kinetically to determine the effectiveness of the established kinetic model;
[0008] Step four: static and dynamic compression and stretching tests are performed on damping elements such as porous energy-absorbing structures, oil pressure energy-absorbing structures, and air pressure energy-absorbing structures to obtain the kinetic characteristic parameters of the damping elements;
[0009] Step five: based on the kinetic characteristic parameters obtained in step four, the kinetic model of the equivalent damping element is established in combination with the kinetic model established in step three;
[0010] Step six: based on the equivalent kinetic model established in step five, the spacecraft body kinetic model is assembled to form the overall spacecraft kinetic model. The simulation results of the model are used to evaluate the influence of key factor parameters.
[0011] Preferably, in step one, the structural components in the spacecraft main body and the rod frame type multi-stage energy-absorbing buffering system are regarded as elastic bodies, and a parameterized geometric model is established. The multi-stage energy-absorbing buffering system is connected to the spacecraft main body through rotating pairs A and B. The multi-stage energy-absorbing buffering system is connected by foot pads, main support rods, and auxiliary support rods, and is arranged orthogonally along the spacecraft main body. The main support rods and the auxiliary support rods are connected by spherical hinge pairs, and the foot pads and the main support rods are connected by spherical hinge pairs.
[0012] Preferably, in step one, the motion parameters include the lateral attitude deviation of the spacecraft main body, the landing roll angular velocity , the yaw angular velocity , the pitch angular velocity , the landing vertical velocity v x , the horizontal velocity v y , and the horizontal velocity v z . The force element parameters include the local ground landing aerodynamic load P, the buffering force F of the internal energy-absorbing buffering system of the main support rod, the friction force f, and the damping force f d .
[0013] Preferably, in step one, the main support rod includes oil pressure, air pressure energy-absorbing components, and porous energy-absorbing structural components for absorbing energy during the landing buffering process of the spacecraft. According to the connection relationship and working principle of the spacecraft rod frame type landing energy-absorbing buffering system, the connections, constraints, motion parameters, and force elements between all components are modeled using mathematical equivalent models, and all parameter variables are parameterized.
[0014] Preferably, in step two, the parameterized kinetic model of the damping element multi-stage energy-absorbing buffering system established includes the oil pressure fluid density , the maximum stroke of the buffer , oil hole area , oil hole flow coefficient , gas polytropic index , gas initial pressure and the logical expression relationship between the gas pressure area a.
[0015] Preferably, step four carries out compression and stretching test under quasi-static state for the middle damping element such as porous energy-absorbing structure, oil pressure energy-absorbing structure, gas pressure energy-absorbing structure and the like, carries out modal test under dynamic state, and obtains the mapping relationship between the external reaction force f of the damping element and the compression stroke d, the dynamic stiffness coefficient k and the like.
[0016] Preferably, the equivalent dynamic model in step five is corrected by combining the dynamic characteristic parameters obtained in step four with the dynamic model established in step three, and a real data model based on the physical characteristics of the damping element is formed.
[0017] Preferably, in step six, the equivalent dynamic model established in step five is combined with the spacecraft main body model to form a spacecraft overall dynamic model through connection and assembly. Through the model, simulation analysis of various contact and collision interface working conditions (rigid ground, concrete ground, local star soil ground and the like), various landing attitude parameters (single support rod landing, double support rod landing, four support rods landing at the same time), and multiple targets (landing energy-absorbing buffer acceleration response, landing energy-absorbing buffer collision load) is carried out, the stress, strain and load spectrum of the concerned components are obtained, and the influence of the key factors such as the number of uses and the service life of the concerned components is evaluated. BRIEF DESCRIPTION OF DRAWINGS
[0018] It is a flow chart of the spacecraft multistage energy-absorbing buffer system dynamic modeling method of the application.
[0019] It is a schematic diagram of the spacecraft rod frame type multistage energy-absorbing buffer system of the application, wherein 2(a) is a side view and 2(b) is a top view.
[0020] It is a schematic diagram of the equivalent model of the porous energy-absorbing structure component of the application.
[0021] It is a schematic diagram of the equivalent model of the oil pressure-gas pressure energy-absorbing structure damping element of the application.
[0022] It is a schematic diagram of the load spectrum when the foot type pad block contacts and collides with the star ground of the application. DETAILED DESCRIPTION
[0023] In order to make the above objectives, characteristics and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.
[0024] A flow of a spacecraft multi-stage energy absorption buffer system dynamics modeling method is shown in Figure 1 , comprising the following steps:
[0025] Step one: establish a geometric model of the spacecraft multi-stage energy absorption buffer system, and parameterize the pre-attention variables in the structural design parameters; the spacecraft multi-stage energy absorption buffer system is connected by the spacecraft main body 1 and the landing buffer system through the rotary joint A5 and the rotary joint B6. The multi-stage energy absorption buffer system is connected by the foot pad 4, the main support rod 2 and the auxiliary support rod 3, and is arranged along the spacecraft main body in a circumferential orthogonal manner. The main support rod 2 and the auxiliary support rod 3 are connected by a spherical hinge joint, and the foot pad 4 and the main support rod 2 are connected by a spherical hinge joint. The main support rod 2 includes an oil pressure energy absorption structure, an air pressure energy absorption structure and a porous energy absorption structure, etc., which are used to absorb energy in the spacecraft landing buffer process, as shown in Figure 2 According to the working principle of the spacecraft multi-stage energy absorption buffer system, an equivalent model of the connection parameters, constraint parameters, motion parameters and force elements is established, and the pre-attention design parameter variables are parameterized; according to the connection relationship and landing working principle diagram of the spacecraft multi-stage energy absorption buffer system, the components in the spacecraft main body 1 and the landing buffer system are regarded as elastic deformers, and all design variables are parameterized; the connection constraints 5 and 6 of the spacecraft main body 1 and the landing buffer system and the connection constraint 7 of the main support rod 2 and the auxiliary support rod 3 all adopt equivalent models based on mathematical description, which constrain three translational degrees of freedom and release three rotational degrees of freedom; the connection constraint between the foot pad 4 and the main support rod 2 adopts a fixed constraint, which constrains all motion degrees of freedom. The connection position coordinates of the spacecraft main body and the main support rod , the connection position coordinates of the spacecraft main body and the auxiliary support rod , the connection position coordinates of the main support rod and the foot pad , the outer diameter and length of the main support rod , the outer diameter and length of the main support rod piston rod , the outer diameter and length of the auxiliary support rod , the outer diameter of the foot pad , the maximum stroke of the oil pressure and air pressure , etc. are parameterized.
[0026] The spacecraft main body transverse attitude deviation , the landing roll angular velocity , the yaw angular velocity , the pitch angular velocity , the landing vertical velocity v x , the horizontal velocity v yHorizontal velocity v z Motion parameters are parameterized as variables; the collision between the spacecraft and the star surface takes three forms: rigid ground, local star soil ground, and concrete ground, etc. The landing attitude of the spacecraft is divided into single support rod landing, double support rod landing, and simultaneous landing of four support rods.
[0027] Step Two: Based on the parameterized geometric model and parameterized mathematical equivalent model established in Step One, establish a parameterized dynamic model of the multi-stage energy-absorbing buffer system with parameterized damping elements; during the spacecraft landing multi-stage energy-absorbing buffer process, applied force elements such as local gravitational acceleration are used. The direction is vertically downwards, and the local ground landing aerodynamic load It acts on the center of mass of the spacecraft and is perpendicular to the spacecraft's axis. The oil pressure and air pressure inside the main support rod are expressed by equation (1):
[0028] Buffer elasticity It can be expressed by the following formula:
[0029] (1)
[0030] in, The density of the hydraulic fluid; The liquid flow coefficient; This represents the area of the oil pores during compression. This represents the area of the oil pores during compression. This represents the initial volume of the buffer cavity. This is the initial air pressure; To buffer the travel; These represent the areas of the hydraulic chamber, piston, and oil hole, respectively; k is the gas pressure polyvariance index.
[0031] Porous energy-absorbing structural components buffer force This is a unidirectional process, and the non-elastic recovery after compression is expressed by equation (2). Its displacement versus load curve is shown in [reference needed]. Figure 4 .
[0032] (2)
[0033] in, , The load corresponding to the displacement of the crushing point of the porous structure; Loading factor.
[0034] Step 3: Based on the dynamic model established in Step 2, perform dynamic analysis on all estimated design variables affecting the buffer performance of the damping element's energy absorption and buffering parameters to obtain the axial force, shear force, bending moment, and torque of each connecting joint. Spacecraft center of mass acceleration Contact and collision forces between the foot-type pad and the star array (normal force, lateral friction force) (e.g., to ensure the dynamic model can be solved smoothly, thereby determining the effectiveness of the established dynamic model);
[0035] Step 4: Conduct static and dynamic compression and tensile tests on damping components such as porous energy-absorbing structures, hydraulic energy-absorbing structures, and pneumatic energy-absorbing structures to obtain the external loads on the damping components. With displacement The curve parameters, for each structure, are at least Group experiment ( ), Not less than 6, then take Group weighted average;
[0036] Step 5: Based on the information obtained in Step 4 - The curve parameters, combined with the dynamic model established in step three, will be obtained from the experiment. - The equivalent dynamic model of the damping element established in step three of the curve parameter correction and fitting process ensures that an effective and reasonable dynamic model is obtained.
[0037] Step Six: Based on the equivalent dynamic model established in Step Five, and combined with the physical connection relationships established in Step One, assemble it with the main dynamic model of the spacecraft to form the overall dynamic model of the spacecraft. Through simulation analysis results of this model, obtain the axial force, shear force, bending moment, and torque of each connecting joint. Spacecraft center of mass acceleration Contact and collision forces between the foot-type pad and the star array (normal force, lateral friction force) Through comparison and iteration with design indicators, the impact assessment of key factor parameters is finally carried out.
[0038] This invention enables dynamic modeling of multi-stage energy-absorbing buffer systems for spacecraft. The method of this invention has been applied to the research and development of buffer landing systems for Chinese spacecraft, providing strong support for the application of multi-stage energy-absorbing buffer systems for spacecraft.
[0039] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.
Claims
1. A spacecraft multi-stage energy-absorbing buffer system dynamics modeling method, comprising the following steps: Step 1: Establishing a geometric model of the structure of the spacecraft multi-stage energy-absorbing buffer system, and parameterizing the pre-attention variables in the structural design parameters; establishing an equivalent model of the connection parameters, constraint parameters, motion parameters and force elements according to the working principle of the structure of the spacecraft multi-stage energy-absorbing buffer system, and parameterizing the pre-attention design parameter variables; Step 2: Based on the parameterized geometric model and the parameterized equivalent model established in step 1, a parameterized dynamics model of the multi-stage energy-absorbing buffer system with damping elements is established; Step 3: Based on the dynamics model established in step 2, for all design variables of the damping element energy-absorbing buffer parameters that are estimated to affect the buffer performance, dynamics analysis is performed to determine the effectiveness of the established dynamics model; Step 4: Static and dynamic compression and tension tests are performed on the damping element to obtain the dynamics characteristic parameters of the damping element; Step 5: Based on the dynamics characteristic parameters obtained in step 4, the dynamics model of the damping element is established in combination with the dynamics model established in step 3; Step 6: Based on the equivalent dynamics model established in step 5, the spacecraft body dynamics model is assembled to form a spacecraft overall dynamics model; the influence of key factor parameters is evaluated through the simulation analysis results of the model.
2. The method of claim 1, wherein, The damping element includes a porous energy-absorbing structure, an oil pressure energy-absorbing structure, and a gas pressure energy-absorbing structure.
3. The method of claim 2, wherein, The geometric model in step 1 includes a spacecraft geometric model and a multi-stage energy-absorbing buffer system geometric model, and the parameterization in step 1 refers to assigning parameter variables to the design of the model.
4. The method of claim 3, wherein, The spacecraft geometric model includes mass, inertia, outer envelope length and diameter; the multi-stage energy-absorbing buffer system geometric model includes a landing buffer system opening angle of a rod frame, a main rod sleeve and a number of stages, a porous energy-absorbing structure, an oil pressure energy-absorbing structure, a gas pressure energy-absorbing structure, an auxiliary rod joint, and a foot buffer pad.
5. The method of claim 4, wherein, Based on the geometric model in step 1, external loads, motion parameters, connection and constraint boundary conditions are established according to the actual motion state and working principle of the structural components.
6. The method of claim 5, wherein, All parameter variables of the dynamics model established in step 2 are completely parameterized, and the model is automatically updated according to the changes in the initial conditions.
7. The method of claim 6, wherein, In step 3, dynamics analysis is performed on all design parameter variables to determine the effectiveness of the dynamics model of the multi-stage energy-absorbing buffer system damping element.
8. The method of claim 7, wherein, In step 4, static / dynamic compression and tension tests are performed on the damping element to obtain the dynamics characteristic parameters of the damping element.
9. The method of claim 8, wherein, In step 5, the equivalent dynamics model of the damping element is based on the comparison, correction and fitting of the analysis results in step 3 and the test results in step 4.
10. The method of Claim 9, wherein, In step 6, the spacecraft overall dynamics model is assembled based on the equivalent model of the damping element established in step 5 and the spacecraft body model, and the influence of key factor parameters is evaluated through the simulation analysis results of the spacecraft overall dynamics model.
11. The method of claim 10, wherein, Through the simulation analysis of multiple contact collision interface conditions, multiple landing attitude parameters and multiple targets by the spacecraft overall dynamics model, the stress, strain and load spectrum of the concerned components are obtained, and the influence of key factors such as the service life of the concerned components is evaluated.
12. The method of claim 11, wherein, The contact collision interface conditions include rigid ground, concrete ground and local star soil ground.
13. The method of claim 11, wherein, The multiple landing attitude parameters include single support rod landing, double support rod landing and four support rods landing at the same time.
14. The method of claim 11, wherein, The multiple targets include landing energy-absorbing buffer acceleration response and landing energy-absorbing buffer collision load.