CONTROL ALGORITHMS FOR STABILIZING UNDERACTUATED ROBOTS

Three control algorithms are developed to stabilize an underactuated t wo-link robot at its unstable inverted position. The well-known linear quadratic regulator is described first. Next, a stabilization control law using partial feedback linearization is developed where the refer ence trajectories for the linearized degrees of freedom are designed b y analyzing the zero dynamics. The linear quadratic regulator and part ial feedback linearization control algorithms both assume an exact dyn amic model. To deal with modeling inaccuracies, a robust controller us ing sliding mode concepts is supplied. Numerical simulations are prese nted. (C) 1998 John Wiley & Sons, Inc.