Robust stabilization of a flexible space platform: an H∞ coprime factor approach

An H_∞ based design procedure has been applied to the attitude control of a flexible space-platform. The design approach incorporates a two stage procedure. The first stage is a loop-shaping procedure which shapes the open-loop gain to give desired characteristics. The second stage is a robust stabilization design on this `shaped´ plant using a new coprime factor approach to H_∞ optimization. The control of flexible space structures with uncertain parameters has been the subject of a number of design studies, and it is demonstrated that the technique is simple and is effective in producing acceptable performance and robust stability properties. The paper reviews the use of H_∞ optimization in controller design, briefly describes the coprime factor robust stabilization problem, introduces the two stage design procedure, and applies the techniques to the control of a hypothetical but representative flexible space structure