The Intelligent Systems Research Institute (ISI) of the National Institute of Industrial Science and Technology (AIST) has successfully carried out basic experiment of running with a human-sized humanoid biped robot HRP-2 Leg Module for Running (to be designated as HRP-2LR, hereinafter), 127cm tall, weighing 31kg and 12 degrees of freedom in all, in collaboration with Kawada Industries, Inc. (to be designated as KAWADA, hereinafter).

Up to now, small-sized humanoid robots of height less than 60cm and capable of running have been developed. But running with a human-sized humanoid robot taller than 120cm is a world first feat. It should be noted that with an increased size, mechanical impact for running grows greater, and a new technology for generating specific motion pattern is to be developed for keeping balance with an armless robot leg in the course of running.

Throughout the research work, Dr. Shuuji Kajita, a senior researcher of ISI-AIST, and Mr. Takashi Nagasaki, a doctor course student of Tsukuba University, took charge of developing the control software, while KAWADA was engaged in the development of HRP-2LR hardware.

In the future, efforts will be paid for improving running speed and efficiency and adaptation to running over a rough road surface.

Photo: HRP-2LR in running experiment

Studies on running robots have been carried out since the middle of 1980s in the United States, Japan, Canada, Germany and other countries. Most of these robots have a large spring equipped within each of their legs, just like a hopping toy to ensure smooth running. Most of the resultant robots are non-humanoid running machines, which are able to run effectively, but not to walk so well. In 1996, Honda Motor Co., Ltd. (to be designated as HONDA, hereinafter) announced the development of Humanoid Robot P2, stimulating studies on humanoid robots not only in Japan but also in the world. As a part of this trend, urge for implementing running with a humanoid robot has been augmented. In December 2003, Sony Corp. (to be designated as SONY, hereinafter) announced world first running success with a small-sized humanoid robot QRIO.

The ISI-AIST has been engaged in the study of running control as a part of efforts to extend the humanoid robot mobility.

The robot HRP-2LR used in this work is an upgraded version of HRP-2L, which was developed through a 5-year Humanoid Robotics Project (HRP) under the METI (Ministry of Economy, Trade and Industry) program. The HRP-2LR is characterized by lighter weight and faster speed.