PURPOSE: To exclude an affection caused by contact with the environment and errors in modeling, by simultaneously using impedance control and sliding mode control.

CONSTITUTION: An input value τi for an object 1 to be controlled is computed by the use of an impedance control model 2 for performing impedance control in accordance with errors e, e' from desired values xd, xd' for output values x, x' delivered from the object 1 to be controlled. During controlling for the object to be controlled in accordance with the computed input value, a sliding mode control model 4 for performing sliding mode control in accordance with the errors e, e', is used in addition to the impedance control model 2. Further, a parameter included in the sliding mode control model 4 is changed in accordance with a disturbance F applied to the object to be controlled from the environment 3, and accordingly, the input value τi is compensated by adding a compensating value τv thereto so as to remove an affection by the disturbance F from the output values x, x'. Accordingly, it is possible to an affection caused by contact with the environment and errors in modelling.