  We address modeling and control of a gate access automation system. A model
of the mechatronic system is derived and identified. Then an approximate
explicit feedback linearization scheme is proposed, which ensures almost linear
response between the external input and the delivered torque. A nonlinear
optimization problem is solved offline to generate a feasible trajectory
associated with a feedforward action and a low level feedback controller is
designed to track it. The feedback gains can be conveniently tuned by solving a
set of convex linear matrix inequalities, performing a multi-objective
trade-off between disturbances attenuation and closed-loop performance.
Finally, the proposed control strategy is tested on the real system and
experimental results show that it can effectively meet the requirements in
terms of robustness, load disturbance rejection and tracking performance.
