Evolving competitive car controllers for racing games with neuroevolution

Modern computer games are at the same time an attractive application domain and an interesting testbed for the evolutionary computation techniques. In this paper we apply NeuroEvolution of Augmenting Topologies (NEAT), a well known neuroevolution approach, to evolve competitive non-player characters for a racing game. In particular, we focused on The Open Car Racing Simulator (TORCS), an open source car racing simulator, already used as a platform for several scientific competitions dedicated to games. We suggest that a competitive controller should have two basic skills: it should be able to drive fast and reliably on a wide range of tracks and it should be able to effectively overtake the opponents avoiding the collisions. In this paper we apply NEAT to evolve separately these skills and then we combined them together in a single controller. Our results show that the resulting controller outperforms the best available controllers on a challenging racing task. In addition, the experimental analysis also confirms that both the skills are necessary to develop a competitive controller.