Optimal pure-pursuit missile guidance

The endeavor of the pure-pursuit guidance is aligning the missile velocity vector with the line-of-sight to the target. The classical pure-pursuit guidance is not the preferred choice for a guidance law as it does not perform well against moving targets. Albeit this, its appealing feature and the main advantage are that it needs measurement of angle only for implementation, thus reducing the cost at the price of the performance. To this day, the implemented guidance law for classical pure-pursuit is mostly a constant proportional control law, and acceptable miss distance is achieved for stationary and very slow targets, thus the use for engagement of moving targets is limited. This paper's objective is to use the optimal control theory in the design of the guidance law for pure-pursuit guidance and to assess the performance against non-stationary/moving targets and deterministic disturbances. The main conclusion is that applying the optimal control theory to design optimal guidance laws for pure pursuit improves performance and reduces the miss distance below a meter for a moderate target’s velocity. The Optimal Pure-Pursuit Guidance Law for stationary targets is shown to realize the Proportional Navigation guidance law.