The influence of obstacles on the collective motion of self-propelled objects

We investigate the influence of obstacles on the collective motion of self-propelled objects in the framework of the 2D Vicsek model. The obstacles are arranged in a square lattice and have a circular shape. We show that by increasing the radius of the obstacles the collective motion of the self-propelled objects can be altered from super-diffusive to diffusive. For obstacles with small radii, the system is composed of large clusters moving in one preferred direction, for larger radii, the system is composed of small clusters moving randomly in different directions.