  In this paper we present some results obtained with a troupe of low-cost
robots designed to cooperatively explore and adquire the map of unknown
structured orthogonal environments. In order to improve the covering of the
explored zone, the robots show different behaviours and cooperate by
transferring each other the perceived environment when they meet. The returning
robots deliver to a host computer their partial maps and the host incrementally
generates the map of the environment by means of apossibility/ necessity grid.
