Modal Analysis of the Slitted Membrane Used in the Voice Prosthesis Capable of Sound Production

Abstract

Abstract. A voice prosthesis is a surgically implanted device used to restore speech in patients who have undergone laryngectomy, typically due to cancer. The existing voice prosthesis only works as a bypass valve which allows air flow from the trachea to the esophagus. Here, a novel membrane-based voice prosthesis was designed which actually helps in sound production, and modal analysis was conducted to study its natural frequency. The unique feature of this design is a slitted membrane, whose vibration helps in sound production. Initially, a stretched circular membrane was simulated and validated with analytical results. The same analysis was performed on a slitted membrane. The variation in modal frequency due to load (line pressure), membrane thickness, and slit dimensions was studied. It was observed that with an increase in load and length of the minor axis, the frequency of vibration of the membrane increases. The frequency of vibration of the membrane decreases with an increase in the length of the major axis. The membrane thickness had a unique effect on vibration frequency. At higher loads, increased thickness decreased frequency due to increased mass. At lower loads, frequency initially decreased and then increased with thickness, as membrane stiffness played a significant role in vibration. This paper provides a promising insight into the importance of the slitted membrane and its parameter in producing sound.