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Updated: May 23, 2026
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Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
Advanced vibration suppression algorithms in adaptive optics systems
Carlos Correia1, Jean-Pierre Véran, Glen Herriot
1National Research Council, Herzberg Institute of Astrophysics, Victoria, British Columbia, Canada. carlos.correia@nrc-cnrc.gc.ca
Summary
This study introduces a novel multirate algorithm for vibration suppression in astronomical adaptive optics (AO) systems. The new method effectively reduces vibrations even at low sampling frequencies, improving image quality for telescopes.
Area of Science:
- Astronomy and Astrophysics
- Optical Engineering
- Control Systems
Background:
- Adaptive optics (AO) systems are crucial for next-generation telescopes, but vibration suppression is a significant challenge.
- Laser tomographic AO systems rely on natural guide stars, often faint, necessitating lower sampling frequencies that can coincide with vibration frequencies.
Purpose of the Study:
- To develop and evaluate a novel multirate algorithm for vibration suppression in astronomical AO systems.
- To compare the proposed algorithm against existing solutions for improving low-order mode correction.
Main Methods:
- A novel multirate algorithm based on the linear-quadratic-Gaussian (LQG) approach was developed.
- The algorithm utilizes upsampling to correct vibrations at higher frame rates.
- Numerical Monte Carlo simulations were performed using realistic AO system parameters and Keck Observatory telemetry.
Main Results:
- The multirate LQG algorithm demonstrated significant vibration reduction across a wide range of sampling frequencies (20-800 Hz).
- Effective vibration suppression was achieved even when sampling frequencies were below the vibration frequency (e.g., 29.5 Hz).
- The algorithm provided the least residual error for both faint and bright guide stars across various vibration peak widths.
Conclusions:
- The novel multirate LQG algorithm offers a superior solution for vibration suppression in astronomical AO systems.
- This method enhances sky coverage and image quality, particularly for faint guide stars and challenging vibration conditions.
- The findings are applicable to current and future large-scale astronomical observatories.
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