Orientation control and short distance path planning for the N-Boat sailboat robot
Autonomous sailboat, PI control, Robot path planning, Path optimization, Genetic algorithms
Researches related to wind-propelled boats automation has grown rapidly over the past 15 years. Some challenges arise when developing a completely autonomous sailboat robot such as short-term path planning, sailboat control, sensors data acquisition, and electrical supply. This work proposes a low-level control strategy and also a short-term path planning method for autonomous sailboat that is capable of dealing with upwind situations. In order to solve these problems, first a method to find the best low-level controller according to each application was developed. The method uses PI controllers, finding a table that contains the best proportional and integrative parameters for the application, obtained through simulations. Then, a short-term path planning method for autonomous sailboat that is capable of dealing with upwind situations was devised. Basically, the path planning method uses the distance ranges available (longitudinal and lateral) for the maneuvering and the sailboat desired heading to generate points in-between, which are reachable given the wind restriction. Finally, the path planning method was optimized, using genetic algorithm. The optimization method uses the path planning parameters to come up with finding an optimal path. The results demonstrate feasibility and usefulness of the method.