This paper presents a leader-follower methodology for a group of robots to converge and track a two-dimensional curve defined by using implicit function. A control law is presented for the leader robot, which has the knowledge of the curve function, so that the leader robot can converge to and circulate along the curve. Moreover, a group of follower robots is controlled by using a potential function to track the given curve by surrounding the leader robot. The stability and converge of the mobile robot network with the addressed control algorithms are studied in this paper. Simulation results with a group of five and ten follower robots are introduced to validate the development control system.
Experimental results with omnidirectional mobile robots are also presented.

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