A port-Hamiltonian approach to the control of interaction

In many applications, a robot has to interact with the surrounding environment in order to perform some useful task. When a manipulator interacts with an object a very profound change occurs. In fact, before the contact, the controller has to control only the motion of the robot; after the contact, the manipulator dynamically interacts with the environment and the controller has to manage a new dynamical system made up by the robot coupled with the environment. It has been proven in [328] that even if the controlled robot is stable in case of free motion, its behavior could become unstable when there is a contact with the environment. © 2007 Springer-Verlag Berlin Heidelberg.