Synchronization Control for a Mobile Manipulator Robot (MMR) System: A First Approach Using Trajectory Tracking Master-Slave Configuration

In cooperative tasks, the ability to keep a kinematic relationship between the robots involved is essential. The main goal in this work is to design a synchronization control law for mobile manipulator robots (MMRs) considering a (2,0) differential mobile platform, which possesses a non-holonomic motion constraint. To fulfill this purpose, a generalized trajectory tracking control law based on the computed torque technique, for an MMR with n degrees of freedom, is presented. Using Lyapunov stability theory, it is shown that the closed loop system is semiglobal and uniformly ultimately boundedness (UUB) stable. To add position-level static coupling terms to achieve synchronization on a group of MMRs, the control law designed for the trajectory tracking problem is extended. Both experimental and numerical simulation results are presented to show the designed controllers performance. A successful experimental validation for the trajectory tracking problem using an 8 degrees of freedom (DoF) robot model (KUKA youBot) is depicted. Finally, numerical simulations in the CoppeliaSim environment are shown, which are used to test the synchronization control law made on the hypothetical scenario, where a two robot system has to manipulate an object over a parametric trajectory.