8 SERVO 10.2017
Q. I’d like my robot to make some sound effects and talk. Where do I start?
A. Excellent! Adding sounds and/or speech to a robot is useful and can really bring it to life. Let’s start off easy. Even simple beeps are useful for giving audible
feedback from a robot. Most any processor can be
programmed to play beeps or a tune using commands like
TONE, SOUND, or FREQOUT. Here’s an Arduino playing
various tones: https://www.youtube.com/watch?
You can find code on the Web for many different
processors and tunes, and play
them through a small piezo or
amplified speaker. Specifying a
tune sequence consumes
program memory. A notable
exception is the PICAXE 08M2
which has four built-in tunes:
Happy Birthday; Jingle Bells;
Silent Night; and Rudolph the
Red Nosed Reindeer. Great for beginners, the command is
simply PLAY pin, tune. Many years ago, I built a fairly
complex electromechanical game prototype using a BASIC
Stamp 2 to control motors and generate all the electronic
sounds. You can see it at https://www.youtube.com/
watch?v= NDcNmoZjgA8. Most of the program space
was taken up with various loops and FREQOUT commands.
These days, I’d call that the long way around, but it
serves to show that (with patience) even a simple processor
can make a variety of sounds.
Regular speakers require a constant audio signal to
create audible output. Generating sound is a “blocking
command” for many processors, as no other processing can
go on until the sound stops. So, even generating a simple
steady beep stops everything. (Pretty annoying!)
One workaround I like to
use is a tiny 11 cent beeper.
Search “mini ACTIVE buzzer” on
eBay; for instance
#142211794545, 10 for $1.13.
Figure 2 shows these tiny
devices, just 7/16” diameter and
5/16” tall. It’s a self-contained
by Eric Ostendorff
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Warning, Warning! A big Roboto shoutout to Television’s B- 9 “BubbleHeaded Boobie” — everyone’s favorite wise-cracking robot from the 1960s shown in
Figure 1. Episode #1 of Lost in Space states that October 16,
1997 was the original launch date of Jupiter 2, so we’re rapidly
approaching the 20th anniversary of Irwin Allen’s vision of the
I was five years old when this series started in 1965, and
the show was a staple of my youth. “Robot” (as everyone called
it) was designed by Bob Kinoshita, who had also designed
Robby the Robot from Forbidden Planet. Sharp-eyed roboticists
can easily spot several similarities between the two.
Both robots appeared together in the LIS episode “War of
the Robots” ( https://www.youtube.com/watch?v=
9WGYGXjkKrk). And who can forget, “Trip Through the
Robot” ( https://www.youtube.com/watch?v=zN2jrpLfT9Y).
Finally, just for fun, here’s a video of “The Challenge,” showing
Kurt Russell looking even younger than he did in the opening
scene of “Guardians of the Galaxy 2” at https://www.you
Now, let’s dive in to our question of the month.