NIPPONIA No. 38 September 15, 2006


Special Featuresp_star.gifLiving with Robots

"Japan leads the world in the research and technical development of humanoid robots," says Inoue Hirochika, formerly in charge of the government's Humanoid Robotic Project.

Humanoid Robots Continue To Evolve

They can climb stairs, run, and pick themselves up if they fall over. Humanoid robots are getting better and better at moving like human beings. They can already operate heavy equipment, push a wheelchair, serve tea, and learn other useful tasks. The day when people will interact with them on an everyday basis is not too far off.

Written by Torikai Shin-ichi
Photos by Enomoto Yoshitsugu


ASIMO's stage performance always pleases the crowd at the National Museum of Emerging Science and Innovation (Miraikan) at Odaiba, Tokyo.

Top: "Our latest ASIMO can 'run' at 6 km/h, walk hand-in-hand with someone who needs guidance, and push a wagon," explains Shigemi Satoshi.

Bottom: Early version, soon after research on two-legged walking robots began.

(Photo credits: Honda Motor Company)

Taking the first step

Japan's development of humanoid robots took a big step forward in December 1996, when Honda Motor Company unveiled its walking robot. P2, the two-legged ASIMO prototype, was stable on his "feet" and caught many researchers completely off guard.

At the time, the general assumption was that no one could make a two-legged walking robot. When researchers saw P2 they finally realized the potential for humanoid robots.

But why would Honda, an automotive manufacturer, develop a humanoid? "The answer lies in Honda's realization that mobility is founded on the ability to walk," explains Shigemi Satoshi, a researcher involved in developing ASIMO.

Honda began developing two-legged walking robots in 1986. Its researchers examined how humans and animals walk, and studied medical textbooks to learn about human joints, especially their shape and the role they play in motion. For these humanoid robot developers, the first job was to research the human body. They developed technology to make these machines walk on two legs, and made a number of prototype machines that could replicate lower body movements.

The ASIMO prototype P2 weighed 210 kg and stood 182 cm tall. Honda's P3 came out the next year, in September 1997, and was smaller and lighter: weight 130 kg, height 160 cm. P3 led to the development of ASIMO. It is 120 cm tall and weighs 52 kg.


"Robots are about to evolve more quickly than ever before. That's for sure," predicts Hirukawa Hirohisa of the National Institute of Advanced Industrial Science and Technology. He is standing between two HRP-2 humanoids.

Robots to help people

Around the same time, in 1998, Japan's Ministry of International Trade and Industry launched its own program, the Humanoid Robotic Project (HRP). Most of the work was assigned to the National Institute of Advanced Industrial Science and Technology (AIST). The goal was to make a humanoid robot that could help people in their daily lives. The early research was based on Honda's P3.

By 2003, the Institute had developed its own humanoid, HRP-2. They managed to make it quite small (height 154 cm, weight 58 kg). Its freedom of motion around the waist is a big advance. Its arms are strong, and if it falls on its behind it can stand up again on its own. It can climb into a heavy-duty vehicle by itself and operate it, like a person.

"Ideally, humanoid robots will be able to operate in the same environment as humans, using the same tools and offering some good economic benefits. Of course, they should have a somewhat human shape—otherwise people might find it difficult to associate with them," says AIST's Hirukawa Hirohisa.

HRP-3, the Institute's latest prototype, was developed in the fall of 2005. It can work outdoors because it is more resistant to dust, dirt and rain.


HRP-3 prototype unveiled in September 2005. It is more resistant to dirt and rain, so it finds outdoor chores no problem at all.

A person operating HRP-2 by remote control. The more advanced HRP-3 can learn simple tasks.

A more flexible "brain" and a softer body

"Humanoid robots should be able to work as our personal assistants. There's a special need for them in Japan and other developed countries where populations are aging," says Inoue Hirochika, an honorary professor of the University of Tokyo who was the HRP project leader.

"The idea is to have them obey you. When you get old and weak, you'll want them to understand orders like 'Go fetch that for me,' and 'Hold this for me.' In other words, we need machines that can help us live independently and free of physical restraint. And it would be good to get the price down to about the same as a car."

This sounds a bit like ASIMO, who is just a few steps away from becoming a human partner.

What still keeps these robots from being our partners? "Well, for one thing, the body and head should be fairly soft. They'll be safer to interact with when their bodies are softer, and they'll be more clever when their 'brains' can think more flexibly."


HRP-2 operating a backhoe, wearing protective clothing to keep off the dirt and moisture.