On a workbench in an upstairs bedroom, more small robots are under development, scattered amid snippets of wire, solder, and sheets of specially designed, wafer-thin circuit boards. Still more are tucked into cases that shuttle back and forth among exhibitions and museums. Officially, Mark Tilden is a robotics physicist at Los Alamos National Laboratory in New Mexico, but he is principally interested in what he calls biomorphic robots. Unlike conventional robots, which are usually based on digital technology, Tilden's nervous-network machines are based on analog technology using continuously changing waves, rather than ones and zeroes. Instead of writing elaborate programs to make his robots walk, he designs circuits that automatically seek a desired state.
Motion is usually the result.
When his robots encounter obstacles, they frantically try to get back on track, sending out a blizzard of almost random impulses until they manage to scramble past the obstruction. Given the contrast between the fluid motions of his inexpensive machines and the stiff, clumsy behavior of many more-costly robots, it is little wonder that the bombastic Tilden enjoys the role of vocal skeptic about the digital world and professes enjoyment of the drubbing he sometimes gets. That's an exaggeration. Tilden returns e-mail with unnerving speed. At the same time, he's serious about advocating analog.