A robotic human masticatory system: kinematics simulations

Abstract

A robotic device is proposed by means of which the mastication process could be reproduced in a mechanically controllable way whilst the masticatory efficiency and/or food dynamics are assessed quantitatively. A robotic model of the mastication system is developed according to biomechanical findings about the jaw structure and muscles of mastication, where each of the major muscles, temporalis, masseter and pterygoid, are responsible for the masticatory movements is represented in a linear actuator and muscle origin and insertion are modelled as a spherical joint placed between the mandible and the skull. This forms a robotic platform model with the mandible being a moving plate and the skull a ground plate. To validate the robotic model, extensive simulations of forward kinematics, i.e., producing the mandible movements with given muscular actuations, and inverse kinematics, i.e., generating the muscular actuations required for a given human chewing pattern have been conducted using the SolidWorks and COSMOS/Motion. Results are given and discussed in terms of trajectories of key reference points, such as incisor and time-history of actuations.