M-TRAN (I, II, III)

Overview

M-TRAN (Modular Transformer) is a self-reconfigurable robot built by AIST and Tokyo Tech from 1998, led by Satoshi Murata and Haruhisa Kurokawa with Eiichi Yoshida and others. Each module joins a half-cube block and a half-cylinder block with a link. Its hybrid design works both as a lattice robot that rebuilds itself and as a chain robot that walks or crawls. The same modules can walk as a four-legged robot and then turn into a snake to enter narrow spaces. Gaits came from Central Pattern Generator controllers tuned with genetic algorithms. M-TRAN I and II used magnets and shape-memory-alloy actuators to connect, which was slow and power-hungry. M-TRAN III switched to a faster mechanical hook connector. In 2008 the team reported self-reconfiguration with up to 24 modules running identical software. M-TRAN III gave more than 200 public demonstrations at EXPO 2005 in Aichi. Later systems such as SMORES and Roombots also use jointed modules that dock with each other. M-Blocks took a much simpler route, with no external moving parts.