UNDERSTANDING, DESIGNING & CONSTRUCTING ROBOTS & ROBOTIC SYSTEMS
■ BY VERN GRANER
TRY, TRY AGAIN
“I have not failed. I’ve just found 10,000 ways that won’t work.”
— Thomas Alva Edison
IF AT FIRST YOU DON'T SUCCEED ... DON'T TAKE UP SKYDIVING! Yes, I
know "try again" has to be one of the oldest work-related clichés. However,
many times if you turn over a dusty old cliché, you find a kernel of truth
nestled under it. In this particular case, that kernel is persistence pays. My
direct experience has taught me that nothing is ever as easy as it looks.
Experience has also taught me that when things get complicated, a
methodical and consistent approach is typically the best course of action.
Problems seem to be a natural part of development, so encountering them
should come as no surprise and you certainly shouldn't let possible
(or actual) problems stop you from building. If you've started building, it
means you have something to work on, something to improve.
YOU MAY ASK YOURSELF
HOW DID THIS GET HERE?
Sometimes, when we see a finished project, we can
only picture it in its finished form. It seems as if it sprung
fully-formed from the mind of the creator directly into being.
In my career, this has never been the case. I have to design,
then prototype, then test (lather, rinse, repeat!). I evaluate
what works in the prototype and what doesn't. I then revisit
the design and make changes. Sometimes the creation and
testing of a prototype reveals better ways that the idea might
be implemented. Other times, things just don't work no matter
how the diagrams, datasheets, and experts insist it should!
In this month's article, I'm going to give you a behind
the scenes tour of the more notable projects I've been involved
with and the hidden problems we encountered along the way.
I hope to document how these projects would never have come
to fruition if not for many people's tenacity in overcoming
problems and improvising solutions. I'll begin with one of the
single biggest projects upon which I've worked, The Ponginator.
THE PONGINATOR MK-I
Back in the December ‘07 issue of Nuts & Volts, I
introduced The Ponginator MK-I, a 20 foot tall smoke-spewing,
light-flashing, music-playing, siren-wailing robot with quad-barrel
pneumatic ping pong ball cannons. It was the centerpiece of The
Robot Group's presentation for the very first Maker Faire in Austin,
TX. In the days leading up to that event, we had struggled with
various issues including multiple prototype ping pong ball propulsion systems, leaky air lines, and a stripped cannon pan motor.
In spite of those challenges, the Ponginator was assembled
on-site the day before Maker Faire opened and performed
much more smoothly than anyone could have imagined. The
Ponginator was an unmitigated success. It operated amazingly
well for something that, in only 30 days, went from a pencil
sketch to towering over the arena floor. This was just the beginning of the Ponginator's career, and more problems would present
themselves as we tried to adapt it to changing requirements.
THE PONGINATOR MK-II
When it came time for the next event, we figured it would
be easy to just bring out the Ponginator and set him right
back up. Unfortunately, when we visited the proposed site, we
discovered that we would be in an outdoor area. In the original
design, we hadn't considered the challenges an outdoor venue
would pose. For starters, the MK-I used a two-story construction
scaffolding as a frame and was wrapped with a tarp. There
was concern over how we would keep the whole thing from
toppling over if the wind picked up. To be safe, we needed
to redesign the frame and find something fairly substantial
to use as an anchor. Time to put on the thinking caps!
November 2009 61