Configuration And Deployable Analysis Of Arm-shaped Tensegrity Structure

With the rapid development of the aerospace field and people’s requirements for large space developable mast are getting higher and higher.The traditional mechanical articulated connection method increases the weight and design complexity of the structure,and the tensegrity structure has attracted much attention because of its light weight and good ductility.At present,there is no systematic summary and analysis on the axial splicing method of tensegrity structure,and there is no unified specification and theory on the splicing method.The design of tensegrity structure applied to developable mast structure is not perfect,it is still in the stage of exploration and improvement.First,the mathematical modeling of the basic configuration of the three-bar tensioning unit is completed.The basic configuration of the axial splicing idea is induced and summarized.The two 3-bar tensegrity units with different rotating angles in units are connected along their axes to obtain 4 types of two-layer tensegrity structure composed of two3-bar tensegrity units.The relation between the minimum radius and the basic parameters of the configurations is derived by analyzing the interior space of the four configurations.Then,the ranges of the main structural parameters for assembling the two 3-bar tensegrity units are determined.Then SVD is applied to solve the equilibrium equations in order to obtain the pretensions of all the members.Influences of the the main parameters on the pretensions are used to correct the ranges of the main parameters.And through the static analysis of each configuration,the influence of load and gravity on the deformation of the configuration is analyzed,so as to obtain the mechanical property difference among the configurations.Then,configuration 1 and configuration 3 with good malleability were selected,and the two-layer 3-bar splicing unit topology was transformed into a multi-layer multi-bar tensegrity splicing structure,and the general component matrix and connection matrix were completed to form a complete general mathematical modeling and program.Preload analysis is carried out for multi-bar and multi-layer splicing structure,and the distribution law of preload is obtained.Finally,according to the main technical indicators of the design of the developable mast,the deployment plan of the tensegrity developable mast is analyzed and summarized,and a suitable deployment plan is selected.Through the comparison of different driving modes and model experiments,the driving modes and spring deployment are determined.By analyzing the node position of the interference-prone parts in the process of folding,the correction range of the ratio of height to diameter and the overlap rate is found.The overall mechanism design of the extension arm is completed from the aspects of the arrangement of the cable rod connector,the spring and the cable member and the choice of the drive motor.The method of dynamics simulation is used to verify the rationality of the developable mast.