Design of a biologically inspired parallel robot for foods chewing

To quantitatively assess food texture changes and/or masticatory efficiency during chewing, the jaw movements and, chewing/biting forces must be measured. For this purpose, a robotic solution has been proposed to reproduce the human chewing behavior. The chewing robot of parallel mechanism is based on the biological finding that the mandible is pivoted at the temporomandibular joints and driven by groups of muscles for opening and closing of the mouth. This paper reviews the biomechanics of the mastication system, defines the kinematical mechanism of the chewing robot, and describes the design of the actuation systems. With a linear actuator for a muscle group of mastication, its spatial placement between the mandible or moving plate and the maxilla or ground plate follows the line of action and attachment sites of the muscle. The design requirements for each actuation system are mainly specified as the actuation range, velocity, and acceleration, and the actuation force, which are determined by inverse kinematics analysis via a simulation software and the jaw force analysis via Pythagorean theorem, respectively. A design of the physical linear actuation, which is made up of a rotary motor, a gear reduction train, and a leadscrew, is presented, whereas the challenges are discussed for building the entire chewing robot.