Page 131 - Robot Builder's Bonanza

Chapter 10

Build a Motorized

Plastic Platform

his chapter details construction of the PlastoBot, the base for a small but peppy robot
Tthat’s constructed using 1/8″-thick plastic— most any plastic will do, so if you already have
a piece in your garage feel free to use it. I built the prototype PlastoBot using 3mm (about
1/8″) expanded PVC.
PlastoBot is basically a square, and making it involves only straight cuts. The corners of the
plastic are chamfered— lopped off at a 45° angle— to enhance the looks and to prevent the
base from snagging on things. You can build the robot with or without cutouts for the wheels.
The cutouts can be tricky to make, but they allow the robot to retain its sleek design by keep-
ing the wheels inside the profile of the base.
The PlastoBot as described here is 4″ square, but the design is scalable. As desired, you can
make it larger . . . or smaller, if you have teeny- tiny motors and wheels. The practical maxi-
mum is about 10″ square. For any base larger than 5″ or 6″ you should double the thickness
of the plastic— from 1/8″ to 1/4″.
G I provide the exact model number for each of the pieces you need, but remember that you’re
free to substitute parts for others if you already have them or if you’ve found substitutes that are
cheaper or easier to get.

Making the Base

Refer to Table 10-1 for a list of parts.
Figure 10-1 shows the completed PlastoBot. It measures 4″ square and is balanced on one
end with a small plastic ball caster. (If you don’t want to use a ball caster, you can provide the
bot with a static skid, using an 8-32″ 1″ machine screw and acorn nut. See the end of
Chapter 8 for a quick description of the idea.)

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