CHAPTER 24
Body Building
A robot’s body provides a framework to which you can attach various components and circuit boards. The
body protects the robot’s innards against battering damage as well as environmental harm. The body can
make a robot convenient to carry and straightforward to store. Often overlooked as a consideration, the
robot’s body strikingly affects the way humans perceive the robot.
This chapter begins with some common approaches to developing robot bodies. The rest of the chapter
explains how you can create a body like Sandwich’s for your line-following robot.
Approaching Robot Bodies
Sometimes you’ll run across a wonderful enclosure, container, or case that you feel you must build a robot
around. In that case, you’re done with body selection! However, most of the time you’ll perform a careful,
deliberate body-selection process. Often, form follows function.
Ethereal Drafting—Thinking About the Robot
When beginning a project, you’ll probably have a basic idea of what you want the robot to accomplish. The
work to be performed by the robot dictates the approximate quantity and complexity of the sensors, circuits,
and motors.
At first, body designs are explored mentally. With infinitely strong, inexpensive, and moldable material,
what would be the ultimate shell for the robot you have in mind? After many iterations of shapes are
considered and discarded by the brain, the rough body figure (including width and height) and variety of the
materials (metal and plastic) are subsequently constrained.
Sometimes rough sketches on napkins or on the reverse side of boring meeting agendas further focus
the potential benefits or pitfalls of conceptual designs.
Vision Revision—Accepting Constraints Based on Available Parts
At some point, cold reality sets in. It’s time to peruse the home-laboratory stockroom (junk pile) and read
through catalogs to determine which parts are realistically attainable.
Available motors, wheels, and batteries tend to have the largest reductive impact on potential robot
bodies. It’s helpful to physically lay out all of the major parts, including candidate breadboards, and to
rearrange them like puzzle pieces until a harmonious configuration emerges.
The width and mass of the motors play a significant role in the robot’s shape. The selected motors
specify the minimum battery voltage and current. The total mass and sizes of the motors and batteries
combined suggest whether metal or plastic is required.