Development of tetrahedral type rehabilitation device using flexible pneumatic actuators

Rehabilitation devices help to recover physical ability of patients. This study aims to develop a home rehabilitation device which can be safe to use while patients are holding it by hands. In the previous study, as a portable rehabilitation device, the flexible spherical actuator that was able to give motions to patients while handling it was developed. The device can give rehabilitation motion for upper limb by only changing the relative position of patient's hands. However, the tested device cannot give absolute position for hands for rehabilitation of shoulders. In this study, we aim to develop a low-cost and simple home rehabilitation device for shoulder that can change absolute position of the device. In this paper, to realize position change of the flexible spherical actuator, the development of a tetrahedral type rehabilitation device using extension type flexible pneumatic actuators is described. The construction and the operating principle of the tested device is also described. The attitude control using the tested device and an embedded controller is also carried out. As a result, it can be confirmed that the absolute position of the object can trace the desired coordinate relatively well.