Inducing wrist twist during arm swing by using gyro effect

Abstract

We propose a device that controls arm twist motion by applying rotational force to wrist by gyro effect only while users swing their arms. Gyro moment occurs when an object rotates around two independent axes. In this paper, we use two rotational axes in two different motions to control user’s arm twist motion. One is their own arm motion: such as a swing of an arm. And the other one is our device that is mounted on the arm with rotating disks. By using this device, user’s wrist voluntarily rotates based on a gyro effect. We used two rotating disks for controlling the amount of gyro moment. For instance, no gyro moment is generated when two disks rotate on the same angular velocity and opposite direction of rotation. In this paper, we show that our prototype system can induce wrist twist as a result of swing down of an arm.