Transient dynamics during the orbiter based deployment of flexible members

The 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 mission ranging from deployment of antennas, booms and solar panels 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. To get some appreciation as to the complex interactions between flexibility, deployment and attitude dynamics as well as to help pursue stability and control analysis, the equations are linearized about their nominal deflected equilibrium configuration. The procedure is applied to the Space Shuttle based deployment of plate-like members. Results suggest substantial influence of the inertia parameter, flexural rigidity of the appendages, orbit eccentricity, deployment velocity, initial conditions, etc. on the system response. This would indicate additional demand on the orbiter's control system during construction of space-platforms.