Tendon-driven Elastic Telescopic Arm -Integration of Linear Motion and Bending Motion-

The telescopic structure has a high extension-to-contraction ratio and is suitable for using a long manipulator that reduces the size of the structure because it is lightweight and small in diameter. There is a problem that conventional telescopic structures are only used in an open environment because it can not avoid obstacles on the axis of extension. In this paper, we propose a linear mechanism that can extend and contract one node at a time by a linear movement mechanism using a slide screw, and clarify its effectiveness by experiments. In addition, we control the tip position of the arm by the rope winding length and discuss the accuracy quantitatively. In addition, by integrating the linear mechanism and the bending mechanism, we achieved the linear motion while avoiding obstacles on the axis of extension.

I. Introduction

When using a robot for investigation or inspection in a complex environment such as a disaster site where debris is scattered or inside of a nuclear reactor with many facilities, it is desirable to use a long manipulator that can pass through a narrow route avoiding obstacles. When manufacturing a long manipulator, there is a problem that the volume and weight of the manipulator become excessive because a conventional manipulator requires a high power drive system to support a heavy arm. Therefore, in order to overcome the mass increase of the manipulator, the weight reduction of the mechanism and the weight compensation mechanism are installed.