Measuring system for parallel moving ships

The paper introduces algorithm for determining the relative positions of two ships manoeuvring as a pair. This algorithm also takes into account determination of angle ă, which is difference between present approaching vessel and guidance vessel course. Relative positioning system is a vision system based on three colours LEDs matrix and rotating CCD camera. There are presented ways of distance calculation based on photogrammetric methods from the known distance between the characteristic points of the real. Several possible cases are taken into account. The considerations have been illustrated on the basis of model of the system. These results confirm the correctness of the operation of the algorithm that is used by the designed measuring system.