Multibody Dynamics Incorporating Deployment of Flexible Structures

Abstract

The equations of motion for a flexible structure during deployment from and retraction into a base that is part of an open-loop multi-body chain are derived. The eigenfunctions of a fixed-free beam are used as the shape functions and their properties are exploited to express various domain integral terms as explicit functions of the instantaneous deployed length. The essential contributions of the present paper are the modeling of flexible body deployment with mass transfer and a recursive solution method for the dynamics. The deployment or retraction of space structures such as the SAFE Extension Mast can be simulated using this model. The model is presented in a format that is suitable for implementation in multibody dynamics codes.