Interaction Force Control of Robots with Variable Stiffness Actuation

In this paper, the control of the force due to the interaction with the environment of a robotic manipulator with relevant and adjustable joint stiffness is addressed. It is assumed that the interaction force is not directly measurable and a controller able to estimate this force is proposed. Also the problem of controlling simultaneously both the position and the stiffness trajectory in the robot workspace is investigated. Moreover, the proposed controller provides useful information for the implementation of collision detection/reaction strategies. The proposed control approach has been validated by means of the simulation of a two-link planar manipulator.