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Updated: Aug 15, 2025

Fabrication and Testing of Microfluidic Optomechanical Oscillators
Published on: May 29, 2014
Design of Active Vibration Isolation Controller with Disturbance Observer-Based Linear Quadratic Regulator for
Yuchen Qian1,2, Yong Xie1, Jianjun Jia1,2
1Key Laboratory of Space Active Opto-Electronics Technology, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
Abstract:
The optical reference cavity in an ultrastable laser is sensitive to vibrations; the microvibrations in a space platform affect the accuracy and stability of such lasers. In this study, an active vibration isolation controller is proposed to reduce the effect of vibrations on variations in the cavity length and improve the frequency stability of ultrastable lasers. Based on the decentralized control strategy, we designed a state-differential feedback controller with a linear quadratic regulator (LQR) and added a disturbance observer (DOB) to estimate the source noise. Experiments were conducted using an active vibration isolation system; the results verified the feasibility and performance of the designed controller. The accelerations along the axis (Z-, X-, Y-) directions were suppressed in the low-frequency band within 200 Hz, and the root-cumulative power spectral densities (PSDs) declined to 1.17 × 10-5, 7.16 × 10-6, and 8.76 × 10-6 g. This comprehensive vibration met the requirements of an ultrastable laser.
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