There was a little ghost that would use its hands to alternately cover, then reveal its eyes like as with the classic children’s game of “Peek-a-Boo.” It was cute. Okay, it was adorable! However, what was really impressive was that it was done
with industrial rotatory pneumatic actuators, solenoid
valves, and a PLC. Being in the business of building
packaging and production line machinery, I could tell the
equipment used in the video was a bit pricey.
Vern and I discussed the project, and decided the
same motions could be easily accomplished with a couple
of standard servo motors and a simple microcontroller for
probably $50 or less. After I added a PIR motion sensor, a
sound playback board, and some LEDs for eyes, I
presented Veronica and Don with their new ghost.
So, if it’s way past time for you to add to your creepy
collection of little Halloween horrors, it’s time to build
your own Peek-a-Boo Ghost!
I find Halloween is always a fun time of the year. In my neck of the woods, it seems more
money is spent on Halloween decorations than almost any other holiday. My friends,
Veronica and Don Chaney are a good case in point. It's their favorite time of the year and
they go all-out decorating their house (Figure 1). I like to tease Don during the holiday by
showing Veronica the latest and greatest decorations — to Don’s (or actually his wallet's)
dismay. I often get poked right back by
him when he bugs me to build a couple
of new automated creatures to add to
their monster menagerie. Normally, I go
into hiding at that point, but this year
my friend, Vern Graner (full disclosure:
he works for this magazine and is a
Halloween nut too!) was showing me a
couple of Halloween videos and one by
Widgetwerks (see Resources) really
caught my eye.
18 September 2014
FIGURE 1.
BuildthePeek-a-BooGhost