Effect of friction and control parameters on the tracking accuracy of a target seeker

Abstract

The tracking accuracy of a missile target seeker depends on many variables. For a target seeker using a gimbaled platform, an important variable is the friction induced by the preloaded bearings, and by the short wires which connect the target detector with the rest of the seeker's electronics. This friction force is nonlinear and sufficiently large enough such that accurate position tracking of a target, whether stationary or moving, is difficult. Conventional control methods such as P.D. (proportional plus derivative) or P.I.D. (proportional plus derivative plus integral) control action can not satisfactorily meet the error criteria. To overcome the deficiency of these two methods, a model-reference method has been synthesized, relying on idealized predictor corrector control to improve the tracking accuracy of the missile seeker. Computer simulations using the Dynamic Simulation Language have demonstrated the superior performance expected from this method.