Impedance control

Impedance control is an approach to the control of dynamic interaction between a manipulator and its environment. This type of control is suitable for environment interaction and object manipulation. The key theory behind the method is to treat the environment as an admittance and the manipulator as an impedance. It assumes the postulate that "no controller can make the manipulator appear to the environment as anything other than a physical system." Hogan's rule can also be stated as: "in the most common case in which the environment is an admittance(e.g. a mass, possibly kinematically constrained) that relation should be an impedance, a function, possibly nonlinear, dynamic, or even discontinuous, specifying the force produced in response to a motion imposed by the environment."