Improvement of vibration isolation characteristics by Kalman-filter estimated acceleration feedback

The dynamic displacements of micro vibration isolation systems still need to be suppressed because the precision accuracies in Hi-tech manufacturing industries have currently progressed to nanometer. In this study, the dynamic behavior of a vibration isolation system using a negative stiffness controller is further improved by additional acceleration feedbacks. This improvement is confirmed theoretically and experimentally; however, it causes the system rather costlier when a servo accelerometer is used to measure acceleration. Thus to improve the dynamic behaviors of a vibration isolation system using acceleration feedback without increase of cost, low-cost MEMS (Micro Electrical Mechanical System) accelerometers are used in the developed experimental system. Nevertheless, the acceleration signals measured by a MEMS accelerometer are typically noisy. To overcome this difficulty, a Kalman-filter estimated acceleration feedback is considered in this study.