In this note we propose a controller that solves the problem of coordination of two (or more) robots, under a master-slave scheme, in the case when only position measurements are available. The controller consists of a feedback control law, and two non-linear observers. It is shown that the controller yields ultimate uniformly boundedness of the closed loop errors, a relation between this bound and the gains on the controller is established. Simulation results on two twolink robot systems show the predicted convergence performance.
Rodriguez Angeles, A., & Nijmeijer, H. (2001). Coordination of two robot manipulators based on position measurements only. International Journal of Control, 74(13), 1311-1323. https://doi.org/10.1080/00207170110065893