Explicit Midcourse Guidance Law for Multi-Stage Antiballistic Missile with Solid Propellant

An explicit midcourse guidance law is proposed for a multi-stage antiballistic missile with solid propellant. The powered explicit guidance scheme is modified to consider the ballistic missile intercept mission with the solid propellant. The solid propellant propulsion system does not have cutoff capability, which can only consider the fixed burnout time. In this study, the modified powered explicit guidance algorithm is modified to satisfy the desired position and velocity direction constraints. By appropriately selecting the predicted intercept point based on target ballistic missile dynamics, the desired position and velocity can be determined. The modified algorithm is based on the optimal control theory to minimize the final flight time, which does not require an iterative computation along with the velocity increment at the cutoff time. Numerical simulation is performed to demonstrate the effectiveness of the proposed method for a three-dimensional multi-stage antiballistic missile.