Page 84 - Robot Builder's Bonanza

ROBOTS FROM “FOUND” PARTS 53

Material Pros Cons
Plastic Strong and durable; comes in many Melts or sags at higher temperatures;
forms, including sheets and extruded some types of plastic (e.g., acrylic) can
shapes; several common types of sheet crack or splinter with impact; PVC and
plastic (acrylic, polycarbonate) readily many other plastics are not
available at hardware and home dimensionally stable under stress so
improvement stores; other types can be they can bend out of shape; exotic
purchased via mail order types hard to find; better plastics are
expensive; some specialty tools
required for professional- looking cuts
and holes
Metal Very strong; aluminum available in a Heaviest of all materials; requires
variety of convenient shapes (sheet, power tools and sharp saws/bits for
extruded shapes); dimensionally stable proper construction; harder to work
even at higher loads and heats with (requires more skill); can be
expensive
Composites Lightweight and very easy to cut and Not as strong as other materials;
drill using ordinary tools; allow rapid composites made with paper or wood
prototyping to test new designs and can be damaged by moisture; some
ideas; very inexpensive; come in many kinds may not be as easy to find except
thicknesses at specialty stores or online

Remember! There is no single “ideal” material for constructing robots. Each project
requires a review of:
The robot itself, especially its physical attributes— large, small, heavy, light.
The tasks the robot is expected to do. Robots that do not perform heavy work, such as
lifting objects or smashing into other robots, do not require heavy- duty materials.
Your budget. Everyone has a limit on what he or she can spend on robot materials. Tight
budgets call for the least expensive materials.
Your construction skills. Robots made from wood, plastic, and composites are easier to
build than metal ones.
Your tools. Building robots with metal or thick plastics require heavier- duty tools than
when building wood or thick plastic bots.

Robots from “Found” Parts

Before leaving the subject of robot materials, I want to touch on a special construction style
known as found parts. You’ll read more about the concept in Chapter 16, “Constructing
High- Tech Robots from Toys,” and Chapter 17, “Building Bots from Found Parts,” but here’s
a quick overview.
With found parts you adapt some ready- made manufactured product that you find (in a
store, in your house, on the side of the road) to serve as the base of your robot. Inexpensive
housewares, hardware items, and toys can be used in various creative ways to make robot
building faster and more economical. Examples of found parts include old CDs and DVDs and
plastic container boxes.

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