A vision-based method for estimating vibrations of a flexible arm using on-line sinusoidal regression

A vision-based vibration suppression scheme has previously been proposed to control the vibrational behaviour of long-reach arms operating in fusion reactors. In this paper we describe a new method to reconstruct the vibration using sinusoidal regression. This change makes the overall scheme more efficient since it enables the estimation of the tip oscillation whatever its origin may be. Both an exact solution and a simplified method are proposed to solve the regression problem. To limit the trade-off between good tracking capability and quality of the vibration reconstruction, these regression algorithms are performed over a variable-length sliding window. Consequently this paper also describes the change detection scheme used to automatically adjust the window length. Experimental results validate the proposed method.