DOI: 10.21276/sjet

Pages: 258-266

Large size, light weight and ease of assembly are some of the desirable attributes in design of space structures. The compromise between a large size and low weight results in a structure that is very flexible, but it makes the control of the structure and its components very difficult. Because these structures are large and flexible, they are very sensitive to environmental effects. Further, these structures possess inherently low damping. Therefore, active control schemes are needed to quickly bring the structure back to its equilibrium position when it is subjected to a disturbance. The purpose of control is to damp out structural vibrations to initial excitations. Linear quadratic regulator (LQR) control method is used for control system design in this paper. Though a majority of the work on integrated structure and control design uses a linear quadratic regulator (LQR) for controller design, the influence of state and control weighting matrices on controller performance is ignored. It is proposed herein that the performance of the control system can be improved by selecting optimum values of the cross sectional areas of the members as well as the entries of the state and control weighting matrices used in the LQR design.