The talking skull has been
done to death (heh!), but
seriously, what graveyard or
spooky fall festival would be
complete without a cowled crypt
keeper entertaining the crowd
with giggles and silly banter?
There are a ton of choices
when it comes to talking skull
setups. There are entry level skull
systems that can be had for
under $50 and then there are
high-end commercial systems that
start at $800 and go up from
there. Or, if DIY is your style, the
Internet is loaded with different
self-serve skull systems.
So, what can we do different
that will make our skull stand
head and shoulders above the rest in power, performance,
Introducing the Wee
Talking skulls have come a long way since the original
“Boris” units sold by Gemmy in the late 2000s (Figure 1).
These original skulls used a rather primitive system
consisting of a small DC motor to wind up a string that, in
turn, pulled open the jaw. To drive the motor, you spoke
into a microphone that drove a small audio amplifier.
The output of the audio amplifier was then rectified
and filtered to drive the motor to pull the jaw open until it
reached a “stall” at the end of travel. When the audio level
dropped, a spring would pull the
jaw back to its default “closed”
position and would pull the string
back by unwinding it from the
motor. This simplistic system
provided fairly good audio/jaw
sync as the amplitude of the
audio created a proportional jaw
The next generation of
talking skulls used RC receivers
and servo motors to “puppet”
the jaw. This allowed very precise
control over jaw position, but it
also required a relatively talented
operator and quite a bit of
rehearsal in order to put on a
good performance (Figure 2).
Another step forward came
as folks noticed that servo motors
lent themselves to programming
via computer. With the addition
of a serial servo control board, a computer, and some
homebrew software (or $100 or more to purchase a
commercial program!), you could record servo positions
and synchronize them to sound files. This approach
provided excellent results with pin-point accuracy for jaw
sync, but it was VERY time intensive. Plus, once you had a
show programmed, any change in the audio usually
required you to re-program the entire sequence from
scratch (Figure 3).
September 2017 39
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■ FIGURE 1.
■ FIGURE 3.Visual Servo Automation (VSA) software from
■ FIGURE 2. Talking skull with servo drive and