Fuzzy control application to guidance control for lunar gravity-turn

A fuzzy observer-based mixed parallel distributed compensation (PDC) fuzzy controller is utilized to generate guidance law for lunar gravity-turn descent. First, the Takagi-Sugeno fuzzy model is employed to approximate the probe system. Next, based on fuzzy model, a fuzzy observer-based mixed parallel distributed compensation (PDC) fuzzy controller is discussed in accordance with the definition of stability in the sense of Lyapunov. Robust stability and disturbance rejection technique are also proposed in the design of following guidance control.