A general formulation for librational dynamics of spacecraft with deploying appendages

Abstract

This paper presents a general formulation for studying librational dynamics of a large class of spacecraft during deployment of flexible members. It is applicable to a variety of missions ranging from deployment of antennas, booms, and solar panels from a spacecraft to manufacturing of trusses for space platforms using the Space Shuttle. The governing nonlinear, nonautonomous, and coupled equations of motion are extremely difficult to solve even with the help of a computer, not to mention the cost involved. The equations are being so programmed on an AMDAHL 470-V8 digital computer to help assess the effect of shifting center of mass, nonlmearities, change in inertia of the central rigid body during deployment, number of admissible functions, etc., which complicate the problem considerably. The formulation is ideally suited to help assess the effect of complex interactions between flexibility, deployment, attitude dynamics, and stability for a large family of spacecraft for the present, as well as the next, generation.