External force observer and control for a compliant 2-DOF manipulator

Force or torque control should ensure that a manipulator exerts a predefined force on its environment. In a compliant manipulator the deterministic behaviour of the system can be exploited to estimate this interaction force without a force sensor. In the paper we use a multibody model of a 2-DOF manipulator with flexure joints of which the physical parameters have been experimentally identified. It is shown that this model can be implemented quite straightforwardly in a force control system to apply a constant force on the environment while the end-effector is moving in both directions. Mathematics Subject Classification (2020) 70E55 Dynamics of multibody systems · 70Q05 Control of mechanical systems