Investigating the Design and Manufacture of PneuNet Actuators as a Prosthetic Tongue for Mimicking Human Deglutition

The number of total glossectomy cases in the United States is seeing an increasing trend as per the nationwide inpatient sample database. Patients, who have undergone such aggressive surgical procedures, have extensive limitations in performing basic oral functions such as swallowing (deglutition), eating, and speaking. Current rehabilitation prostheses do little in restoring the functionality of the original tongue. This is true especially in deglutition, which is necessary to transfer a bolus to the esophagus. Such patients need advanced prosthetic devices and through this research, investigations into potential solutions for prosthetic tongues to aid in deglutition were carried out. Different designs were considered and based on a decision matrix, pneumatic networks (PneuNets) were adopted as the foundational basis for generating prosthetic tongue designs. Several prototypes were fabricated that used the Fused Filament Deposition process for producing the mold and silicone Eco-flex 00-30 for producing the mechanism. The resulting mechanism with dimensions 2.4 in. × 1.8 in. × 0.24 in. was powered using pneumatic input and kinematic data was collected. The experiments carried out showed potential in the concept but at the same time, there were challenges related to validating the kinematics and in the transfer of the bolus due to uncontrolled silicone expansions. Details from the literature review, design iterations, simulations, validation processes, manufacturing challenges, and conclusions will be discussed in-depth in this paper.