Master-slave robot position coordination based on estimated variables

In this paper we present a controller that solves the problem of position coordination of two (or more) robotic systems, under a master-slave scheme, in the case when only position measurements are available. The controller consists of a feedback control law and two nonlinear observers. It is shown that the controller yields semi-global ultimate uniformly boundedness of the closed loop errors and a relation between the bound of the errors and the gains on the controller is established. Experimental results show, despite obvious model uncertainties, a good agreement with the predicted convergence.