Robotic Simulator of Vocal Fold Paralysis

Vocal fold disorders impact significantly on quality of life. Specifically, vocal fold paralysis can affect the ability to speak and breathe. To date, there has been a shortage of studies providing a quantitative characterisation of the effect of paralysed vocal folds on the frequency and amplitude of sound in phonation. In this paper we propose a novel bioinspired robotic simulator that physically replicates both healthy vocal fold function and two main pathological conditions in vocal fold paralysis: bilateral and unilateral paralysis. By analysing the audio data produced by our robotic simulator a correlation can be drawn between each type of paralysis and the effects on amplitude and frequency. Results show that in a healthy configuration, frequency response and vocal fold stress are mostly proportional and that their relationship is highly impacted by paralysis. In addition, our experimental results provide a mapping between vocal fold position and tension in our simulator and the resulting sound. These insights will inform laryngeal surgical procedures and help improve the effectiveness of current implant systems.