Build Your Own Combat Robot

Spinner Design
FIGURE 10-8
A spinning
weapon robot.
Chapter 10: Weapons Systems for Your Robot 221
The spinner uses the concept of a flywheel that stores the mechanical energy output
of a motor in a spinning mass to be released in one massive blow to the opposing
robot. The spinner was one of the first successful tactics for inflicting actual damage
on the opposing robot; it remains one of the most dangerous—not only to the target
robot, but also to the spinner robot, the arena, and the audience. Nearly all incidents
of penetrated arena walls and injured audience members have been due to
spinners with more energy than the arena could safely contain.
The earliest spinners were bar shaped, often with hammers or spiked balls on
chains attached to the ends. While simple to build and lightweight, these designs
don’t store as much energy as disk- or ringed-shaped spinning weapons, though
Son of Whyachi has mangled the very best opponents with its three flying spiked
sledge hammers. Thin bar or tube spinners are also more susceptible to bending or
breaking on impact. The ultimate form of the spinner is to enclose the robot completely
in a spinning cone-, dome-, or cylinder-shaped outer shell. With this type of
design, it will be impossible for an opponent to hit the spinner without being
struck by the spinner’s weapon.
Figure 10-8 shows a spinner.
Spinners allow the energy output of a motor to be stored over some time in a kinetic
energy form, ready to be delivered into a target in a moment. This does not
mean that you should use a small motor—the faster your spinner can get up to
speed, the better your robot will fare against a determined and durable opponent.
A spinner that takes more than 10 seconds to spin up may never get the opportunity
to reach top speed; you should design for a spin-up time of 3 seconds or less.