Modern control solution to a precision pointing system stability problem

The feasibility of beyond line of sight reconnaissance using satellite and unmanned air vehicle (UAV) technologies has recently been demonstrated through a program sponsored by the Joint Precision Strike Demonstration Task Force (IPSD)¹. The satellite communication system on the UAV included a two degree-of-freedom antenna positioning system. An instability problem that arose during system integration was eliminated by redesigning the controller using LQ design methods. This controller design effort is discussed. The project is described from a control engineers viewpoint