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Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing

Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing

Published on: February 13, 2018

Bulk wind estimation and prediction for adaptive optics control systems.

Luke C Johnson¹, Donald T Gavel, Donald M Wiberg

¹Center for Adaptive Optics, University of California, 1156 High Street, Santa Cruz, California 95064, USA. ljohnson@ucolick.org

Journal of the Optical Society of America. A, Optics, Image Science, and Vision

|August 4, 2011

Summary

This study introduces a new wind-predictive controller for astronomical adaptive optics (AO) systems. The controller accurately predicts windblown turbulence, significantly improving image quality in realistic conditions.

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Bringing the Visible Universe into Focus with Robo-AO

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Published on: February 12, 2013

Area of Science:

Astronomy
Optical Engineering
Atmospheric Physics

Background:

Astronomical adaptive optics (AO) systems correct for atmospheric distortions.
Predicting windblown turbulence is crucial for enhancing AO performance.
Existing methods struggle with complex, multi-layered atmospheric aberrations.

Purpose of the Study:

To develop a novel wind-predictive controller for astronomical AO systems.
To accurately estimate the velocity of a single windblown layer amidst other aberrations.
To improve the efficiency and performance of AO systems under realistic atmospheric conditions.

Main Methods:

Utilizing fast, gradient-based optical flow estimation to determine wind velocity.
Employing a recursive mean estimator to handle slow-varying turbulence.
Deriving the Cramer-Rao lower bound for wind estimation accuracy.

Main Results:

The proposed controller effectively predicts the motion of a single windblown layer.
The developed estimator approaches the theoretical minimum-variance performance.
Simulations demonstrate significant increases in Strehl ratio using the new controller.

Conclusions:

The novel wind-predictive controller offers a substantial advancement for astronomical AO systems.
Accurate wind prediction leads to demonstrably improved image quality.
This approach is effective even in the presence of complex atmospheric turbulence.