Abstract
In this paper we propose a design method for active vibration isolation with a saturated input. Actuators have limitation of force or torque that can be generated in themselves. In order to overcome this saturation problem we introduce gain scheduling of a controller. The input saturation can be formulated as a nonlinear function and we use the hyperbolic tangent function that is continuous to the output of controller. By introducing this function we formulate the linear parameter varying system according to the input that the controller needs. The controller uses acceleration of the lowest story only as a feedback signal and is implemented to the experimental setup of a four-degree-of-freedom structure. We verify that the control performance is maintained even if a large earthquake comes so that the actuator is saturated, although the fixed H_∞ controller lowers the performance.