OASYS - Opto-mechatronic Active isolation SYStem
An increasing number of high–precision applications require very stable platform, like wafers of semiconductor manufacturing machines, and atomic force microscopes. Emblematic examples of very stringent seismic isolation requirements concerns sensitive equipment of large instruments dedicated to experimental physics, like electromagnets of particle colliders, or mirrors of gravitational wave detectors. The standard procedure is to mount the sensitive equipment on a vibration isolating stage, sometimes referred to as optical table, which can be either passive or active. Typically, commercial optical tables filter out 99 % (or 40dB) of the transmitted vibrations from 1 Hz until several hundred Hertz. However, the achieved stability remains limited by several factors, including magnetic couplings, limited sensor resolution, limited stability of the feedback loops… The objective of this PhD is to develop a ground-breaking active vibration isolation stage, which will drastically decouple the isolated payload from ground vibrations by addressing the aforementioned limitations. The proposed strategy will rely on the combination of high precision interferometric inertial vibration sensors
 and robust control laws .  COLLETTE C., NASSIF F, AMAR J., DEPOUHON C. and GORZA S.-P., A non-magnetic optical inertial sensor, Sensors and Actuators A: Physical (2015).
 COLLETTE C. and MATICHARD F., Sensor fusion methods for high performance active vibration isolation systems, Journal of sound and vibration, 342, 1-25 (2015).