its way down into the crater of an Alaskan volcano, which it explored for the better part of a week. Many six-legged robots have been de- veloped as well.
To develop general approaches to designing robots with legs,how- ever, especially those that walk on two legs as people do, is a compli- cated business that has occupied researchers for years.One well known establishment, the MIT Leg Laboratory, is devoted to the study of locomotion and the construction of legged robots. Other research on two-legged beings is carried out internationally at universities and corporations, with the leading efforts in Japan atTokyo University, the Honda Corporation, and elsewhere. These efforts are central to the widespread proliferation of artificial beings. If they are to work along- side people and interact with them, they will have to be two-legged and generally humanoid so that they can operate in regular human environments and use human devices such as screwdrivers and door- knobs.Another advantage of humanoid robots is the versatility of the human frame. Cheetahs run faster, dolphins swim faster, and chim- panzees exert more strength than humans, but the multipurpose hu- man frame is moderately good at all these things. This adaptability defines the approach chosen by many researchers to build a human- oid robot with similarly broad functionality.
That versatility begins with the ability to walk on two legs, as shown, for instance, by the robots developed by Hirochika Inoue, of the Department of Mechano-Informatics at the University of Tokyo. His latest units, called perception–action integrated humanoid robots, are named H6 and H7.They are human-shaped with head, torso, and limbs but lack facial features and are recognizably mechanical. Condi- tioned as we are to seeing inscrutable movie robots stalk off to carry out their plans, like the faceless Gort in The Day the Earth Stood Still, we might expect H6 and H7 to look menacing—but they are neither hulking nor brutish. They are white in color, and not very big: H7 stands 1.4 meters (4’7”) tall, with a mass of 55 kilograms (120 pounds, including 9 pounds of batteries to power it).
It is illuminating to see H6 and H7 in action because their walk- ing style is almost tentative.When either unit walks, it is accompanied