The optical mouse for vibratory motion sensing

Abstract

The optical mouse has been previously shown to be able to provide highly accurate measurements of slow displacements with a commercial unit with 0.0635mm resolution. Here, its efficiency for vibratory displacements is investigated. It was found that frequency and amplitude thresholds existed beyond which the position-time distributions obtained would not permit analysis. From the analyzable distributions derived, frequency estimation errors below 15% in magnitude could only be comfortably achieved if the frequency was limited to 35Hz and the amplitude limited to 0.4mm, while amplitude estimation errors below 20% in magnitude could only be safely attained if the frequency was limited to 5Hz and the amplitude limited to 0.2mm. This work concludes that the optical mouse technology currently available is workable, but has a confined scope of low frequency and low amplitude application in vibration motion sensing. Nevertheless, this range still makes it useful as a dynamic sensor in a reasonable number of applications where low cost is particularly required. © 2004 Elsevier B.V. All rights reserved.