Servo tracking of targets at sea
This paper details a proposal for the position control system of a two-axis ship-mounted tracker. Aspects of the non-linear dynamics governing Line-Of-Sight (LOS) errors between the tracker and the target are presented. It is shown that the regulation of LOS errors can be achieved by introducing a feed-forward term based on the target's velocity. This velocity is not measurable, and an estimator is required. Given that the tracking problem is non-linear, the classical separation principle does not...