Optimized force and co-manipulation control using stiffness of force sensor with unknown environment

This paper deals with force control and co-manipulation. From a classical control scheme using three closed loops with an external force control, we derive two new control schemes: the first is implemented in order to control the effort applied in a rigid environment and the second focuses on a co-manipulation control in an unknown environment. The proposed control law takes into account the stiffness of the sensor. This consideration is particularly important in the case of rigid obstacles. Experiments were performed with a one degree of freedom robot in order to verify the efficiency of our strategy and to compare the results against another existing controller.