This paper deals with cooperative formation control design for multi-UAVs. A new control strategy is developed to steer a group of robots to three kind of evenly spaced formations: circular, linear and circular sector. Our distributed approach enables real-time formation reconfiguration when the parameters of the formations change or when a robot leaves the formation. Communication among robots is used to maintain the robots equally spaced in the desired formation and to avoid collisions during the reconfigurations. Real world experiments with four mini aerial vehicles demonstrate the efficacy of the proposed formation control strategy.