Page 349 - Robot Builder's Bonanza

Chapter 27

Build Robots with Legs

o you enjoy challenges? I mean the really tough nuts that are hard to crack, the stuff that
Dkeeps you up at night as you try to work through the problems? If so, then maybe you’re
ready to build a walking machine.
Legs are biologically inspired solutions to that old problem of how to get your robot from
here to there. And not only as a means to mobilize your creation, but to step over common
obstacles like yesterday’s lunch bag, your dirty socks, and the family turtle— stuff that might
confound the typical robot with wheels or treads.
In this chapter you’ll learn about the role of legs in creating mobile robots, and the special
requirements and limitations they impose. You’ll read about ready- made solutions, as well as
several designs for making your own six- legged bots on a budget and from scratch.

An Overview of Leggy Robots

With legs, a robot can live among humans, ideally without any kind of special adjustments or
alterations to the environment. Ramps, curbs, steps, stairs, and cracks in the sidewalk all pose
no more of a problem for the robot than they do for any other ambulatory human being.
As of this writing, human- size legged robots that can go anywhere and do anything are still
the province of science fiction. Less ambitious are the full- scale walking robots of industrial
and educational research that show promise but cost a fortune and are known to fall over on
their batteries now and then.
Small- scale legged robots are another matter. With a modest inventory of servo motors and
some specially crafted brackets, you can construct walking bots with two, four, six, and even
more legs. Though they’re more expensive and more demanding to build than robots with
wheels or tank treads, constructing a programmable walkerbot is well within the reach of the
garage- shop tinkerer.

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