Design And Analysis Of A Deployable Articulated Mast Including Flex Parts

With the continuous deepening of space exploration missions, space deployable articulated mast are widely used. Whether the mast can deploy steadily, meet the need of stiffness and strength, and achieve the expected period of service will have a great effect on space exploration missions, even determine its success or failure.Based on the understanding of the development and research situation of space deployable mast and the indicators of capability, a deployable articulated mast including flex parts is designed. The fundamental of deploying and folding is introduced in this paper. On the basis of geometric features and operation state of the mast and its flex parts, a simplified mechanical model of flex part is presented according to results of the stress analysis. Available geometry parameters and material properties of flex parts are given. In addition, the detailed design of driving system is presented.The static characteristic of mast is studied. With the force condition of each node, the stiffness of mast is analyzed. The effect of structural parameters and material properties could effect on the stiffness of the mast are discussed. Further more, the influence of the radius of cable on the stiffness of the mast is calculated using the finite element method.The kinematic and dynamic models are established. The motion equations of any points in the mast are given to study the kinematics characteristics. Dynamic models of deploying is discussed which can figure out the driving torque taking different driving strategies into consideration. Modal analysis are implemented by finite element method and the natural frequencies and mode shapes are obtained.A proper flex part is prepared for the mast, and then a prototype of mast is made to conduct relative tests. The deploying and folding process are proceeded as well as static load test and experimental modal testing. Test results are compared to the theoretical analysis, which indicate that this mast has high compressive stiffness, bending stiffness and is reliable to put into application.