Abstract: Facing the problems of the constrained environment and the constrained velocity ratio between pursuers and evader in collaborated pursuit-evasion games,a "switch" type strategy for scalable swarm of robots to pursue a mobile goal is proposed,in which the swarm is able to finish effectively the pursuit task in dynamic environment while the velocity of the target robot is unconstrained,i.e.,the pursuit robots hunt the target robot in collaboration and with the predominance of numbers to overcome their velocity weakness.In the process of pursuit,the following two behaviors are considered: the moving toward "suppositional potential point" sub-behavior that is task-robot-oriented and the posture matching with neighbor agents(formation).When the distance to goal is farther,the behavior of posture matching is mainly considered,whereas when it is closer,moving toward suppositional potential point is mainly taken into account.Simulated experiments show that the proposed scheme is feasible and effective.