  The development of novel texture adaptations for the management of swallowing
disorders could be accelerated if reliable in vitro tests were made available.
This study addresses some of the limitations of swallowing in vitro models, by
introducing a soft robotic actuator inspired by the tongue. The wettability of
the soft-robotic actuator was engineered to achieve physiologically relevant
contact angles to allow comparing dry and lubricated conditions. The actuator
design and the control algorithm are designed to offer flexibility in the
swallowing patterns to consider different scenarios, including poor lingual
coordination. In vitro swallowing tests with shear thinning liquids were
performed as a proof of concept and showed physiologically relevant oral
transit time, bolus velocity and palatal pressure. Both the bolus rheology and
the coordination of the peristaltic contractions influenced the temporal
evolution of the bolus velocity and the bolus transit time. This novel soft
robotic tongue, its integration in an in vitro oral cavity and its flexible
control can therefore contribute to developing better solutions to manage
swallowing disorders.
