Space transformation method in control of agile interceptors and missiles with advanced microelectromechanical actuators

Interceptors and missiles must demonstrate acceptable performance (agility, maneuverability, controllability, stability, etc.), and different autopilots have been designed. In addition, different guidance control laws have been studied. The needs for improvements of interceptors and missiles guidance and performance in expanded flight envelopes lead to the design of integrated guidance-autopilot tracking controllers. The missile performance is strongly influenced by nonlinear highly coupled longitudinal-lateral dynamics modeled using six nonlinear differential equations (six-degree-of-freedom mathematical model). The linearization of mathematical models are found to be very limited and can be applied only to a very restricted class of flight vehicles. Missiles are controlled by deflecting control surfaces, thrust vectoring, moving mass, reactive jets, and other techniques. Depending upon the missile configuration, which is particularly true for multi-stage missiles, the mathematical models are different. Therefore, general control methods capable to handle nonlinear phenomena and effects are sought. This paper illustrates that superior performance can be accomplished devising novel control procedures based upon complete nonlinear missile-actuators dynamics. A new control design method is reported, and integrated tracking guidance-autopilot control algorithms are synthesized. In this paper, the application of the Hamilton-Jacobi concept and the space transformation method are reported. To validate the results, nonlinear design, simulations, and analysis are performed. High-performance miniscale actuators, fabricated utilizing MEMS technology, are examined to actuate control surfaces. The rigid-body interceptor (missile) and actuator dynamics may have the same order of settling time. Therefore, vehicle and actuators dynamics must be integrated in order to analyze and design high-performance control systems.