To easily realize a feedback control even if previous analysis is absent by learning information on the approximate position of a period orbit and the direction of a period and applying an adaptive tracking method.

A non-linear dynamics system has a continuous branch Bif(X:p) characteristic from period motion to chaos motion in accordance with the change of system parameter. An adaptive tracking part 3 analyzes the response of a non-dynamics system 1 and changes the control parameter (q) of a feedback control part 2 by means of an appropriate rule h(X). Control parameter (q) is decided by the state variable X of the system 1 and system parameter (p), and a feedback control signal with continuous control parameter (q) and the state variable X as references is generated. The feedback control signal is inputted to the system 1 and system parameter (p) or the state variable X is generated. Thus, the desired motion of the non-linear dynamics system 1 can be executed.