Modeling and validation of a planar flexible manipulator

The modeling and validation problem of a laboratory planar flexible manipulator with a link in composite material has been considered. The goal of the paper is to obtain a model useful for the synthesis of feedback control laws. A mathematical linear model, based on the Hamilton principle, is complemented with a nonlinear friction model. Suitable experiments are designed in order to identify the parameters of the model that cannot be measured or analytically computed. Once the single components of the model have been identified, the whole model has been validated with open- and closed-loop experiments. The closed loop validation has been performed using two control strategies. The first one is a single input (position error) single output (motor torque) controller synthesized in the frequency domain and the second one is a multi input (position error and link deflection) single output (motor torque) controller based on a Linear Quadratic (LQ) optimal control law complemented with an observer and an integral action.