Compensation of recording position shifts for a myoelectric Silent Speech Recognizer

A myoelectric Silent Speech Recognizer is a system which recognizes speech by capturing the electrical activity of the human articulatory muscles, thus enabling the user to communicate silently. We recently devised a recording setup based on electrode arrays with multiple measuring points. In this study we show that this allows to compensate for shifts of the recording position, which happen when the array is removed and reattached between system training and application. We present a method which determines the amount of recording position shift; compensation is performed by linear interpolation. We evaluate our method by running recognition experiments across recording sessions and obtain a Word Error Rate improvement of 14.3% relative on the development set and 12.9% relative on the evaluation set, compared to using classical session adaptation.