Development of transformable mobile robot with mechanism of variable wheel diameter

A demand of search and rescue operation using robotic technology increases to mitigate a natural disaster. In such search and rescue tasks, target environment is usually narrow and bumpy world. Therefore there exists a trade-off between high-capability of moving on bumpy environment (which requires large body) and exploration in narrow spaces (which requires small body). To solve such a problem, the authors developed “small-sized transformable mobile robot” that equips with a mechanism of variable wheel-diameter and variable stabilizer-length. The robot (minimized body) can be deployed through a narrow space , and it can surmount relatively large obstacles by expanding its wheel diameter. In this paper, details of the robot system are explained, and geometric analysis of capability of surmounting a step is discussed. keywords: Mobile robot, Search and rescue, Rough terrain, Variable wheel-diameter