Analysis Of Mechanical Attributes And Optimal Design For Deployable Composite Tube Hinge

Thin-wall flexible hinge is a new type of deployable structure that can be used in aerospace,with the advantages of simple structure,high reliability of deployment,good driveability,and strong self-locking.The normal operation of the tube hinge is directly related to the aircraft’s operational performance and the success or failure of the aerospace mission,so the research of its mechanical properties during operation is particularly critical.At the same time,as aerospace missions continue to improve the performance of expandable structures,composite materials with specific strength and stiffness have been better used in aerospace missions.However,composite materials are brittle materials,which are applied to tube hinges,damage and failure may occur during the bending and folding load.The generation and expansion of these local failures will reduce the bearing capacity of composite tube hinges,which will seriously affect the mechanical properties of tube hinge.Therefore,this analyzes the material failure of the mechanical properties of the tube hinge considering damage of the composite material,and then performs a parameter influence analysis and optimization design on the influence of different geometric parameters of the tube hinge on its mechanical properties.The research results have important theoretical significance and engineering application value to improve the stability and reliability of the expandable structure of thin-walled tube hinge space.This article mainly studies the expandable structure of composite tube hinges from the following aspects:(1)A mechanical model of tube hinge considering damage of composite materials was established.Based on the HASHIN failure criterion,the damage initiation and expansion process during the pure bending and dynamic expansion of the tube hinge was simulated,and the feasibility of the composite material for tube hinge was verified.The failure modes,positions of dangerous points and mechanical properties of composite tube hinges in pure bending and dynamic deployment considering damage are studied,and the differences between the failure modes and mechanical properties of the tube hinges in the shell model and the solid model are analyzed.(2)Aiming at the pure bending process of the tube hinge,the Tian Kou method was used to analyze the parameter sensitivity of the mechanical properties of the composite tube hinge,and the key parameters affecting the mechanical properties of the composite tube hinge were determined.Based on the control variable method,different geometric parameters during the quasi-static folding of the tube hinge are analyzed,including the critical bending moment,steady-state bending moment,maximum strain energy,and maximum damage factor of the composite tube hinge.Based on the response surface method,a multi-objective optimization design model with the maximum strain energy and minimum critical moment of the composite tube hinge was established.The optimization model was solved by using an improved genetic algorithm,and a feasible solution distribution was obtained.According to the linear weight method,the optimal solution set was screened again to obtain the optimal design of the tube hinge with the best folding mechanical properties.(3)A detailed finite element simulation of the dynamic expansion process of the tube hinge was performed,and the effects of different geometric parameters of the tube hinge: slot length,slot width,and slot diameter on the overshoot angle,deployment time,and number of vibrations during deployment were analyzed.Through the orthogonal design method,the response surface method was used to establish the optimal design model with the minimum hinge angle of the tube hinge as the optimization target.The optimization problem was solved by the generalized reduced gradient optimization algorithm,and the optimal design of the tube hinge was obtained..(4)A method for topology optimization of composite tube hinges was proposed.The stress conditions at the critical moments of the tube hinges were used to optimize the minimum compliance.The optimization of the grooves shape in tube hinge is completed by commercial software Optimost.The geometric configuration design of the tube hinge with good mechanical properties is obtained,and the similarities and differences between the results of topology optimization and the results of classical parameter optimization are compared.