Design and Development of Active Cord Mechanism “ACM-R3” and its 3-dimensional Locomotion Control

Abstract

This research considers the mechanism design of the“Active Cord Mechanism (ACM) ”, which is a long and slender snake-type functional object that can perform three-dimensional movement. We designed a three dimensional ACM machine named ACM-R3 that can produce large output torque in spite of its small dimensions and light weight, and considered its three-dimensional steering control of two-dimensional serpentine locomotion. The meaning of steering in this research is the route change around the circumference of yaw, pitch and roll axes. Furthermore, novel propulsion forms, such as“Serpentine Locomotion with Lateral-Rolling” (whose control method is based on the steering of the roll axis) and“Sinus-Lifting Locomotion” (which is a special form of pitch axis steering) are examined. The latest model ACM-R3 was used to actually implement, for the first time ever, these new propulsion methods, and also to examine the motion ability experiemntally by measuring the torque produced at each node.