Page 102 - 15 Dangerously Mad Projects for the Evil Genius

CHAPTER 8

Persistence-of-Vision

Display

This project has two parts, an Arduino
PROJECT SIZE: Large microcontroller-based LED unit that sits on top of

SKILL LEVEL: ★★★★ the second part of the project: the motor and motor
control unit. This controls the speed of the motor
that spins the arm with the LEDs.
ATOP THE EVIL GENIUS’ LAIR, there is a sign that is
holographic in appearance and displays the slowly WARNING!
rotating message “Hello.” The sign uses a vertical
line of multicolor LEDs that rotates rapidly, This project has two potentially hazardous aspects.
producing a persistence-of-vision effect (see ■ It spins around quite fast, so if you stick your
Figure 8-1). The main purpose of such a display is fingers into the path of the wooden arm while it
is spinning, it will hurt!
to help the Evil Genius find his way back to the
lair, exhausted after a hard day achieving world ■ The entire project is based on bright flashing
lights. If you suffer from epilepsy, then steer clear
domination.
of it.

Arduino

Central to this project is the Arduino microcontroller
board (Figure 8-2). We will use these boards again
in Chapters 13 and 15.
Arduino interface boards provide the Evil
Genius with a low-cost, easy-to-use technology to
create their evil projects.
Arduino is a small microcontroller board with a
USB plug to connect to your computer and a
number of connection sockets that can be wired up
to external electronics such as motors, relays, light
sensors, laser diodes, loudspeakers, microphones,
and so on. They can either be powered through the
USB connection from the computer, or from a 9V
Figure 8-1 Persistence-of-vision display battery, and can be controlled from the computer

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