Build Your Own Combat Robot

FIGURE 14-2
Chew Toy with
protective armor
removed.
Chapter 14: Real-Life Robots: Lessons from Veteran Builders 309
body frame—the square steel tubing and the wire mesh used for the armor—came
from Home Depot, another great inexpensive supplier. Chew Toy is something
that all designers like—a cheap entry. The cost for this robot (everything but the
speed controller) was about $500. (Instead of doing what I had initially conceived—create
a simple relay system—I splurged on a Vantec speed controller for
Chew Toy. It cost about as much as the entire rest of the robot, but, because the
speed controller is an item that can be reused in future designs, I looked at my extravagance
as an investment. In addition, it saved the time that it would have
taken to construct and properly test the relay system I had devised in the early
phase of Chew Toy’s development.)
Once you figure out what you want to build, the next step is building the
mockup. I cut out a balsa wood frame and the parts into which the motor, the drive
train, weapons system, and so on, will be fit. Balsa is easy to work with, and any
hobbyist who has done original designs of model airplanes, boats, or the like has
probably done mockups in balsa wood. Balsa wood is also cheap and readily
available, and if you botch something in the mockup phase, you can redo it much
more easily than if you were working in metal.
After your balsa wood mockup is within your parameters and everything looks
workable, you are ready to spec out your final project. The balsa wood project
can be broken down into the component parts and used as guides for cutting the
metal for the final project. If you are doing your own metal cutting, you can take
apart your mockup and use each piece as a template for your metal pieces. I laid
the pieces on top of the metal, traced the shape onto the metal, and then cut out the
shapes. That way I was sure all the metal shapes would be the exact size I specified,
and when I cut and fit the bot together it would replicate the mockup.