Fast adaptive guidance against highly maneuvering targets

An adaptive guidance law applicable to a short-range homing missile is investigated against a highly maneuvering target that has the same maximum maneuver acceleration as the missile. In practice, it is difficult to measure the target acceleration with precision and without time delay. The objective of this study is to design a guidance law that can intercept a target within the acceptable miss distance in the presence of unknown target acceleration and guidance command saturation. For this, the main idea of this paper is to apply the fast adaptive control approach to estimating the tangential component of the unknown target acceleration. Moreover, the auxiliary signal is introduced to prevent the presence of the guidance command saturation from destroying the desired adaptive performance. The proposed guidance law can be classified as an augmented proportional navigation guidance (PNG) law with the actual target acceleration component being replaced by its accurate estimate. Simulation results illustrate the satisfactory performance of the proposed guidance law in comparison with other guidance laws with the absence and presence of measurement noise.