Fuzzy guidance law for interception of exoatmospheric maneuvering targets

The relative motion law between the target and the interceptor was analyzed when the divert thruster was on or off. An estimator of the interception ability was proposed based on the relative motion law. On-off conditions for the divert thruster were designed according to the shortest working interval of the divert thruster and the upper boundary of the line-of-sight rate that could be restrained. A novel terminal guidance law was proposed based on the estimator and the on-off conditions. The guidance law took advantage of the experts' experiences to construct the fuzzy rules and adjusted the on-off conditions of the divert thruster based on the relative range and the interception ability. A relay on-off method was utilized to control the divert thruster. The effectiveness and the performance of the fuzzy guidance law are demonstrated through the simulation in which the guidance law is applied to intercept two kinds of maneuvering targets.