Direct impact angle control guidance for passive homing missiles
A guidance problem for impact angle control applicable to a missile equipped with a passive seeker is investigated. The proposed guidance law based on the sliding mode control consists of the proportional navigation guidance term with a varying navigation constant and the additional biased term which is a function of the novel sliding surface. The guidance law directly uses the impact angle error but does not require any range information to be estimated by the additional filter loop of the passive seeker. The asymmetric limit of the passive seeker’s field-of-view is also taken into account, which is not violated by introducing a continuous switching function. The finite time convergence properties are analyzed, and nonlinear simulations are performed to investigate the effectiveness of the proposed guidance law.