To highly precisely realize the position control of a non-linear controlled object such as a hydraulic cylinder.
A model follow-up control system is constituted as a disturbance observer 37 in which a closed loop is constituted of again 34 and a norm model 36 being an integrating element. The input of a feedback controller 28 is obtained as a deviation between a position instruction value θ* and a position detection value θ, and the added result of an output u1 of the feedback controller 28 and the output of the disturbance observer 37 is obtained as a manipulated variable up to a non-linear object 26 to be controlled, and a deviation between the manipulated variable up and the output of a disturbance observer gain L is obtained as the input of the norm model 36, and a deviation between the output and the position detection value θ is obtained as the input of the gain 34. The feedback controller 28 is constituted of a proportional controller, and a gain K is defined as K=J/σ (J is the integration constant of the norm model and σ is the time constant of a target control response), and the following formula, PL1 and Js/L1 is established.
TAKAGI AKIRA
YOSHIMURA TETSUJI
TANAKA KOICHI
