Simulation of a 6-PUS jaw robot and a new mechanism inspired by masticatory system

A jaw robot based on the 6-PUS parallel mechanism was introduced according to the biomechanical properties of mandibular muscles. For a given mandibular trajectory to be tracked, the inverse kinematics solution is derived and Jacobian matrix formulated from differential kinematics is found. Kinematics performances, such as constant orientation workspace and manipulability are simulated via numerical method. These indices show that the parallel mechanism has enough flexible workspace without singularity, and has a good motion transmission performance for human chewing movement. In order to reproduce jaw motions and mechanics that match the human jaw function truthfully with the conception of bionics, the temporomandibular joints (TMJs) are taken into account. Another novel actuation redundant mechanism for the jaw robot is proposed based on mechanical biomimetic principles, which has four degrees of freedom, but is driven by six actuators.