Development of oral-rehabilitation robot

Abstract

It is well known that the massage therapy is useful for the rehabilitation of various diseases. Althoughvarious apparatus have been developed for the massage of the torso and limbs, a machineto perform precise massage therapy to maxillofacial region is not developed yet.Therefore, we developed a robot system that provides massage therapy to the maxillofacialregion. The name of our newly developed robot was WAO-1. WAO-1 has been designedto perform appropriate massage to the patients with dry mouth. System descriptionThe mechanism of WAO-1 consists of two main parts: robot arms and the plungerdevice. The robot arms consist of two 6-DOF (degrees of freedom) manipulators used tocontrol the movement of the plunger device attached to the end-effector of each manipulator(Figure 1). The plunger device is the only part of the robot having direct contact withthe patient face. In order to control the motion of the plungers attached at each arm ofWAO-1, a position control system is implemented. The control system of WAO-1 is composedby a Massage Pattern Generator and Virtual Compliance Control1. Method Anevaluation experiment of WAO-1 is performed. In this experiment, WAO-1 provides themassage to 6 healthy volunteers (without any maxillofacial disorders). Each subject isprovided the massage to its parotid gland for 2 minutes. In order to confirm the effectivenessof the massage provide by WAO-1, the production of saliva was considered as aperformance index. This index is measured by using the Saxon test2; which is a standardmethod to confirm the effectiveness of the massage therapy. Results and discussionThe average production of saliva was increased by 0.63 g after providing the massage. Byanalyzing the collected data with a t-test, we found a significant difference (p < 0.05). Thusthe effectiveness of the massage to the parotid gland by WAO-1 is confirmed. On theother hand, when the doctor gives the massage to the parotid gland of the people, productionof saliva increases 1.4 g (average of 6 people). Therefore, the effect of WAO-1’s massageis less than that of doctor’s massage. We developed a robot system (WAO-1) whichcan massage the face. We think clinical trial is necessary to collect the data to certify theeffectiveness of robotic massage. The goal of this study is to establish robot massagetherapy as physiotherapy.