Dipartimento di Ingegneria informatica, automatica e gestionale

Title: Control of an underactuated mechanical systems for stabilization and stable limit cycle generation: from simulation to real-time experiments
Time and location: Wednesday, 30 nov 2011, at 15:00 in A5

Abstract: This presentation deals with the control of a non-minimum phase underactuated mechanical system, namely the inertia wheel inverted pendulum. Two main problems are treated; the first concerns the stabilization of the system around its unstable equilibrium point, whereas the second one deals with stable limit cycle generation. To solve the first control problem, the nonlinear dynamics of the system is linearized around the equilibrium point and discretized; then a Generalized Predictive Control (GPC) is proposed to stabilize the system. Simulation results as well as real-time experiments are presented to show the effectiveness of the proposed control scheme and its robustness towards external disturbances and uncertainties. To solve the second control problem, the proposed solution is based on partial feedback linearization and dynamic control for reference trajectories tracking. To deal with the unstable behavior of the resulting internal dynamics of the system (which is non-minimum phase) an optimization problem is solved at the beginning of each trajectory cycle to find the best parameters of the reference trajectories with respect to the internal dynamics of the system. The proposed solution for this second control problem has been tested in simulation and implemented in real-time on the experimental testbed to show the obtained results.