Design And Experimental Study Of Lock/release Structure Based On Shape Memory Composites

The space deployable panel structure is an important branch of the space expandable structure,and the deployable panel structure can improve the utilization of solar cells significantly,which plays a vital role in the energy supply of spacecraft.Cubesats is a new space technology,compared to traditional satellite technology,It has small,low cost advantages.With the development of materials science,as a new type of smart materials,shape memory polymers(SMPs)have become a research hotspot.The shape memory polymer and its composite material have the advantages of high specific strength and high rigidity,and have special shape memory effect as a lightweight structural carrier,which can accomplish specific functions.It has a broad Application prospects in the space expandable structure.Based on a thermosetting shape memory polymer composites,a space lock/release structure with shape memory polymer composites as a driving part is designed and developed.Firstly,based on the research foundation of the shape memory material,a method for preparing the shape memory polymer and its composites is described.The shape memory polymer and their composites are tested by the dynamic thermomechanical analysis(DMA)and static mechanical analysis.The basic mechanical properties of the material are characterized.The thermal conductivity and specific heat capacity of the shape memory polymer were tested,and the basic thermal properties of the material at room temperature were characterized.Then,based on the study of the basic properties of the above materials,the structural modeling and working principle of the shape memory polymer composites lock/release structure are analyzed according to the practical application requirements of the cubesat.Based on the theoretical analysis,the shape memory polymer composites lock/release structure of all the components of the size,materials.Determine the shape memory polymer composites lock/release structure works by the heating drive,and accordingly designed for the structure of the use of Constantan-PI heating film.Then,ABAQUS was used to simulate the lock/release structure of shape memory polymer composites,and the safety of the structure was verified.The thermal simulation and analysis of the locking mechanism of the shape memory composite were carried out by UG NX10,and the heating power and heating time of the heating film were determined.Based on the theoretical and simulation results,a space lock/release structure for shape memory composites and a 1: 1 cube satellite model were fabricated.The shape fixation rate and shape recovery rate of the shape memory polymer composites at different temperatures were tested.The reusable performance of the lock/release structure is verified.Finally,the mechanics and thermal environment of during storage,transportation,launch and orbit were reconstructed.A series of ground verification tests including the long-term creep test,the vibration test,the thermal cycle experiment and the deployable function test are carried out.One of the most desirable potential applications of SMPC on cubesats is researched in this thesis.The results show that the shape memory polymer composites has good material performance,can meet the requirements of the space environment on the material,and is suitable for application in the structure of solar panels on cubesats.