Guidance Law For Impact Time Control
A nonlinear guidance law is presented for the im-pact time control of an interceptor against a stationary target.
Exact closed form expressions for impact time and the guidance command are derived. For a given engagement geometry, a
given impact time corresponds to a unique initial heading error. For interceptors launched with any other initial heading
error, a term proportional to impact time error is augmented with the guidance command. The control parameter of the
guidance command is adjusted in a feedback form so that the proposed method is robust to autopilot dynamics. The method
is used in salvo attack, where multiple interceptors are launched for a simultaneous impact.