Fast grid based collision avoidance for vessels using A∗ search algorithm

In this work a real-time grid based collision avoidance algorithm for vessels in maritime environments is presented. Most grid based collision avoidance approaches use Lee´s algorithm to find an optimal collision-free path. The drawback of this algorithm is the long runtime for large grids. To reduce this runtime, in this work the A* search is used instead of Lee´s algorithm. The algorithm additionally regards the physical constrains of the vessel and pays attention to the COLREGs. The runtime and the resulting path of Lee´s algorithm and the A* search are compared in computational experiments. Furthermore, the performance of the collision avoidance on a real vessel on the Lake Constance is presented.