Mechanism Study Of Deployable Cabin For Planet Base

In order to achieve the goal of mankind to outer space,scholars have designed various forms of deployable cabin.Truss Deployable Cabin has the advantages of light weight,large folding ratio,reliable deployment,simple project implementation and so on.In this thesis,the structure,deployment scheme,mechanical properties and dynamic characteristics of the Truss Deployable Cabin was designed and analyzed,and the feasibility of the theory was verified by developing the prototype model of the deployable cabin system.Firstly,in this paper,among various space folding mechanisms,the articulated truss mechanism is selected based on its characteristics such as expansion stiffness,folding ratio,stability,and accuracy.The configuration of several basic deployment units is proposed,and based on the basic deployment unit,several schemes of expandable section systems with different cross sections are established.In addition,the driving scheme of the expandable cabin system is proposed.Due to the coupling of the system,it is difficult to achieve the overall deployment of the cabin system.Therefore,the axial drive scheme and radial drive scheme of the expandable cabin system are proposed respectively.Secondly,in order to simplify the analysis of the deployable cabin system,an equivalent continuous beam model of the truss type extension mechanism is established,and the equivalent stiffness and equivalent mass parameters are derived.Combined with equivalent continuous beam model,the equivalent analysis model of the Deployable Cabin system is established,and the mechanical parameters such as axial tensile stiffness,bending stiffness and torsional stiffness of the Deployable Cabin system are derived.The static characteristics of the Deployable Cabin system are simulated by simulation software to verify the correctness of the theory.Thirdly,the Deployable Cabin system is optimized and its dynamic characteristics are analyzed.Based on the instability conditions of the bar,the range of pretension force applied by the cable is analyzed.The finite element model is established in the finite element software Abaqus,and the factors affecting the natural frequency of the Deployable Cabin system are analyzed by changing the geometric parameters and materials of the members and stay cables.In order to intuitively compare the influence of each parameter on the natural frequencies of the Deployable Cabin system,define the sensitivity of each parameter of the Deployable Cabin system to the natural frequency of the whole system structure and complete the calculation.The influence degree of each parameter is analyzed through calculation results.Finally,the detailed structural design of the Deployable Cabin system is carried out,and a scale-down prototype of the system is completed.Due to the large number of cabin structure systems,it is difficult to build a scale-down prototype of the entire cabin system.This article will build a quarter-ring prototype and a prototype of a stretching mechanism composed of three basic units.The deployment method of the Deployable Cabin system is carried out step by step,and the axial deployment is a one-dimensional stretching motion.Therefore,the radial deployment experiment is mainly verified by a scale-down prototype.