Study on optimum connecting points of boom-membrane structure as a basic model for larger lightweight space structure

This paper presents a first step of suggesting optimization designing on a composite of lightweight membrane and boom structure. In this structure, booms keep rigidity of the whole structure. We believe such structure can be used for deep space exploration in the future as a following and developed version of IKAROS which has already in full success of its self-deployment, self-power generation by thin solar films, and space navigation missions. Or in short-sighted developing vision, this type of structure is going to be applied to the deorbit hardware of low-orbit satellites to earn much drag for atmosphere entry within smaller years. So here we focused on the basic model like a former mentioned type of boom-membrane structure and studied about optimization strategy, and we'd like to suggest to add our research points on the currently recognized as common standard models of deorbit hardware which has just two terminal connecting points on each boom between membrane. Here we studied the efficiency of considering connecting points between boom and membrane from the viewpoint of the reaction force of the booms and wrinkle amount on membrane those are having trade off relations. These parameters are going to be the most critical factor in the future to architect large lightweight membrane structure. Moreover, we formulated this problem as a discrete parameter optimization problem and discussed its efficiency of the optimized model. Furthermore, need of the hoop parts are mentioned as a basic unit of a large repetitive architecture such like solar power plant concept in space.