  In this paper we study multi robot cooperative task allocation issue in a
situation where a swarm of robots is deployed in a confined unknown environment
where the number of colored spots which represent tasks and the ratios of them
are unknown. The robots should cover this spots as far as possible to do
cleaning and sampling actions desirably. It means that they should discover the
spots cooperatively and spread proportional to the spots area and avoid from
remaining idle. We proposed 4 self-organized distributed methods which are
called hybrid methods for coping with this scenario. In two different
experiments the performance of the methods is analyzed. We compared them with
each other and investigated their scalability and robustness in term of single
point of failure.
