Attach the battery
connector into the adapter
cable and slip them under
the front cover.
Next, slide the battery
hatch (rear cover) under the
two middle screws and
secure it with four screws.
You can also secure the
battery hatch with four body
clips, as shown in Figure 21.
You can purchase body clips
Your PBOD is now complete. Take it for a quick spin.
A word of warning though. Don’t run the spinner weapon
more than a few seconds at a time. It gets warm with
extended use and will melt its fasteners. A set of fins on
the trimmer line head would help dissipate the heat.
I used my two favorite 3D printers to make the PBOD
craft shown in Figure 22. The purple PBOD on the left was
printed in PLA on the MakerGear M2. The white PBOD on
the right was printed in ABS on the Afinia. While both excel
on projects like this, the M2 printed the parts in about half
the time. While the Afinia was slower, the small holes were
more accurate and required less finishing. Overall, I am very
happy with the craft that each machine produced.
Well, you might be asking, where is the destruction?
How do they do in combat?
The Plastic Bots of Destruction were better built than I
thought they would be. The trimmer line weapon does not
penetrate the plastic. The best I could hope when battling
them was to chew up the tires. Most of the time it came
down to burning up the spinner motor or running the
battery down to determine a winner.
With a lack of carnage, the battles got to be a little
boring. We had more fun racing the craft around a
makeshift obstacle course. That is not to say someone
could not create a better weapon system. If you do come
up with something, be sure to post a link in the forums so
others can benefit.
While I personally feel the craft failed as a bot of
destruction, they did make for a very agile and robust craft
worthy of Sumo. One could even connect a microcontroller
to the Sabertooth controller for a fully autonomous bot.
You can find the STL files for the various parts on the
PBOD web page at www.kronosrobotics.com/pbod.
In upcoming months, I will be starting a new series
where we will be converting a Proxxon MF70 micro mill to
CNC. Please be sure to post questions and suggestions in
the SERVO Magazine forums at http://forum.
SERVO 02.2014 39
MADE IN THE USA