Modeling identification and control of a 6-DOF active vibration isolation system driving by voice coil motors with a Halbach array magnet

Abstract

The sheet current model considering the end effects is applied to design a six-degree-of-freedom (6-DOF) active vibration isolation system (AVIS) driving by the voice coil motors (VCMs). Compared with the charge model, the sheet current method represents higher calculation efficiency. Then, the hybrid functions (HFs) are employed to identify the multi-input and multi-output (MIMO) AVIS, and the identification parameters are used to design the controller. To promote the control performance, the composite nonlinear feedback (CNF) controller is designed based on the identification parameters. Consequently, the simulations and experiments are carried out, compared with PID controller, the CNF controller shows quicker response and smaller overshoot, i.e., the CNF controller achieves the dynamic damping ratio during the control. Thus, the experimental results demonstrate the better performance of the CNF controller.