Back in 1979, I read
"Build
Your Own Working Robot"
by David L. Heiserman (TAB
Books), a worthwhile book that gave me some of the basic ideas needed to begin
my project. Originally my plan was to build an R2D2. The project soon evolved
into Doctor Who's robot dog K-9. I was fortunate to come across another book "Special
Effects: Starlog Photo Guidebook, Vol 3
" (Starlog Press) with some
BBC blueprints
with most of K-9's measurements and angles. The dimensions on the head are are
kind of screwed up. Overall it turned out better than I expected.
The body of K-9 was built from 1/2" plywood, sheet metal with some Bondo to fill
in the cracks. The ears are formed wire (I think it was a brass welding rod)
with fiberglass screen glued in place. The eyes light up behind red Plexiglas. A
power car antenna with the orange tip of a toy dart extends as the probe. The
tail is a small radio antenna wagged by two solenoids. A hinged metal panel on
the side allows access to the inner components.
The body lifts off of the frame revealing a mess of wires and components. Four 6
volt 8 AH gel cell batteries provide power. There are two rear wheels and one
front wheel. The front wheel has a geared motor built on to it. An old GM wiper
motor with a sprocket and chain from a 10-speed bike steers the front wheel. The
wiper motor is way too heavy and probably draws 10 amps. All motors and
solenoids are controlled by a Commodore VIC20 through relays. The VIC20 has been
totally torn apart and reworked. I even removed the character ROMs to allow for
more program space. New EPROMs provide drive and steering logic as well as sound
effects and speech synthesis. Movements can be preprogrammed through a
calculator keypad or controlled by an Atari joystick. I never got around to
adding RF remote control or ultrasonic collision avoidance.
Technology
and parts availability and changed since the 1980s. Today, Radio Shack hardly
carries any electronic components. Digi-key and Jameco Electronics are still
around. DIY robot kits, surplus computers and laptops are very easy to find.
If I was building a robot today: I would use an old laptop with a
parallel port to control the motors. Light weight rechargeable batteries and
wifi for remote control are already built in. Cordless screwdrivers or drills
are cheap and provide the torque required to move a robot.
K-9 has shown up at several sci-fi shows and conventions in the 1980's. Since
then, parts of him have been stored in my dad's basement and my brother's
garage. While K-9 was in my garage, my wife hit him while parking her car and
broke his neck. Currently he lives in a corner of my garden shed...waiting to be
reactivated someday.