Control for active vibration isolation systems 

Analytical and experimental work is presently carried out to develop improved controllers for the MIM and LMIM vibration isolation systems. Intuitively, the sensed flotor position can be used to make each of the flotor actuator emulate a soft spring-damper system, while the sensed flotor acceleration can be used in a positive feedback loop to emulate a larger flotor mass. The result would be a mass-spring-damper system having a stator-to-flotor acceleration transfer function with very low cutoff frequency. To lower the cutoff frequency in the presence of plant uncertainty, the Q-parametrization and H-infinity and convex optimization are employed.