Page 202 - Robot Builder's Bonanza

EXPERIMENTING WITH “NO- CUT” METAL PLATFORM DESIGNS 171

R2- D2 bots. The plastic trash cans are easy to drill through and cut, for mounting
motors and other parts.
Computer mice: A discarded computer mouse makes a great body for a micro- miniature
robot. Almost all mice can be disassembled by removing one or two screws on the bot-
tom. After removing the circuit board, mouse ball, cable, and switches, you can install
small motors, a small battery, and a one- chip brain.
Compact discs and DVDs: Save the world’s landfill and use these 4.7″-diameter discs for
robot bases. Use care when drilling holes in the plastic: the material can shatter into
very sharp pieces. If you need added strength, sandwich two discs together.
Solderless breadboards: Solderless breadboards are used to experiment with circuits
before using more permanent solder and wire- wrap construction. Mount motors and
wheels on the underside of your solderless breadboard, and you create a versatile and
ever- changeable mobile robot.
Plastic project boxes: These boxes, sold by RadioShack and other electronics stores, are
made to hold custom electronics projects. The boxes come with removable metal or
plastic lids to allow access to the inside. The plastic is easily drilled for mounting motors
and other parts.
Clear or colored display domes: Also called hemisphere or half- round domes, display
domes can be purchased in sizes from about 2″ to over 12″ in diameter. The dome can
be used as the body of the robot or as a cover to protect its electronics. A “robotic ball”
can be made by gluing two domes together. The wheels of the robot spin the ball, which
in turn rolls on the floor.
Metal hardware parts: These include T- braces used for lumber framing in houses. Sizes and
shapes vary greatly; take a stroll down the aisles at the hardware store and you’re sure to
find plenty of candidates. There are lots of sizes to choose from, for making palm- sized
robots to large 50- to 75- pound rovers. More about this idea later in the chapter.
Wide- mouth beverage bottle caps: Looking for cheap and easy wheels for your robot?
Try the plastic cap of that beverage drink you just finished. Aim for the wide- mouth
bottles, the ones with caps measuring 1-1/2″ in diameter. These wheels are just about
the perfect size for use with modified radio control servos. Mount a round servo horn to
the inside of the cap. Hint: Steal the fat rubber band off a broccoli stalk for the tire.
PCV irrigation pipe: All forms of polygonal frames can be constructed using PVC irriga-
tion pipe. Most hardware and plumber supply stores carry PVC pipe in various sizes and
wall thicknesses. Select the pipe based on the size and weight of the robot. Obviously,
you’ll need larger and thicker pipe for the big and heavy robots.

Experimenting with “No- Cut”
Metal Platform Designs

Of all the aspects of robot building, cutting stuff up is my least favorite, especially if it involves
metal. Most designs use stock metal of some kind: U- channel, tubing, strips, or large plates
that must be cut down to size.
But what if you could find metal already in the size and shape you need for building robots?
You can, but this stuff is found in a different part of the hardware store than the stock metal
bins. And with it, you can construct “no- cut” metal platforms that require no (or very little)
cutting to form into usable sizes and shapes.

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