Towards exploration of unknown dynamic worlds using multiple robots

Abstract

In this paper, we present our results on exploration of dynamic worlds using cooperative robots. For our experiments, we used the SimER1 software[1] which is a simulation tool that let us make all our exploration experiments in a simulation environment. Our goal is to make an efficient exploration balancing percentage of map explored, total energy consumed and time required for exploration. We first began using a quadrangular grid map representation as an occupancy system because its simplicity. A simpler world representation requires lesser amount of time in data processing, which is important for dynamic worlds. We made several exploration experiments. First, we measured the exploration efficiency using several exploration algorithms in a semi-static world. Then, we measured the exploration efficiency using an hexagonal grid map representation against the quadrangular grid map representation. Finally, we used the best exploration algorithm and the best of the two representation maps to measure exploration efficiency in a dynamic world. Every experiment was made first using a single robot and then using cooperative robots. The experiments showed that an hexagonal grid map representation minimized the distance among the cells. Furthermore, we found that increasing the number of cooperative robots exploring the area, we reduced the time and energy required to explore the whole area. In average, with more robots in operation, robots consumed less total energy. In this way, we could balance robot costs with total energy and time required for exploration to get the most convenient number of robots to explore the whole world.