Design of guidance law with finite time convergence based on extended state observer

The guidance problem of relative motion of missile-target in the plane is considered, the design problem of the missile terminal guidance law is studied with respect to the two main affecting guidance performance factors associated with maneuver of target and dynamic characteristics of the missile. The first-order dynamic characteristic of the missile is dealt directly in designing guidance law. The extended state observer is applied to real-time rapid estimation of the second derivative of relative distance of missile and target, the first derivative of line-of-sight rate and the rate of acceleration of the target maneuvering. Both linearization of dynamic compensation and finite time stability theory are applied to design a nonlinear guidance law with finite time convergence, such that the missile hits the target accurately. Finally, the simulation results demonstrate the effectiveness and realizability of the guidance law.