(click images for better view)
There's only so much you can do with flashling lights. At some point
a longing for real-world control sets in and then it's inevitable
that the next step is to build a robot... of sorts.
I actually prefer to call this a robotoy
because it is on the very low end of robotics. Sure it runs circles
(literally) around BEAM
robots and it is truly programmable. But whereas this machine uses
2 DC motors without feedback, the roomba
uses optical encoders on each wheel. There are probably a couple
of other differences too. For all I know, real robots may not even
use a hotglued ping-pong ball for support, though I'd find this
hard to believe.
Some things which I could add but probably won't:
- stall sensor
- improved motor control via optical encorder feedback or stepper
- misc sensors
- remote control
- GPS tracking
- vacuum attachment
But did I mention that this robotoy has
The hotglued solderless breadboard was cheap, fast, allows for
infinite flexibility, and doesn't drop parts if held upside down.
I should use this construction method more often.
No schematic ... use your imagination. Actually I haven't entered
the 18X in my schematic capture program.
- 1 Picaxe 18x microcontroller
- 1 L293D motor controller
- 1 solderless breadboard
- 1 AAx8 battery holder
- 2 really cool rubber-treaded robot wheels
- misc wire, scrap plastic for chassis, hotglue
The robotoy works fine for what it does... move in circles, wander
randomly, scare the dog, hold papers on a desk. Using ungeared motors
connected to fairly large-radius wheels, however, is problematic.
It requires substantial current to drive the motors... which requires
more AA cells (8 to be exact) to power the motors... which adds
weight to the chassis... which increases the demand for adequate
current through the motors. Gearing would help substantially. And
while the pingpong ball works, it has drastically different coefficients
of friction when it slides on smooth surfaces compared with when
it slides on carpet. This translates to problems when trying to
figure out how to control the motors to approximate a 90-degree
Some sample code is here
but don't get your hopes up. It only demonstrates the control mechanism.
This code is explicitly released under the GPL.
And this page is licensed under a Creative
Commons Attribution 2.5 License.
Write me if you find this project
useful. Link to this page if it is relevant..
Strobe effect may be psychologically damaging or cause flashbacks
to a pre-color cinema era. This project is provided without any