6 Jan 2003
(updated 7 Jan 2003 at 08:12 UTC) »
Quick Update: The Big Trak's superior size, zero turning radius
and general aesthetic appeal won out, so it's new test
I posted a few pictures of it as it is
the original circuitry lends itself to modification, it was
all removed (except for the shaft encoder and drive motors)
to facilitate testing various sensors and other electronics.
Likewise, the finished version will reside within the
original plastic body, but for now it's been removed for
Right now it's 16F877 powered (soon to have
from the way things are looking) is equipped with HPWM
driven IR detection, an L298 full bridge driver circuit
with diode protection and a linear adjustable voltage supply
with nicads for power.
At the moment it is programmed for simple
avoidance and pet irritation, but compass and sonar
experiments will follow shortly.
BTW, to anyone who's contemplating a small H-Bridge project,
IMO, the L298 is the way to go. It's got built in current
sensing and it doesn't seem to have the hyper-sensitive,
freaky little "noise" issues that plagued the mosfet drivers
It's cheap too, you can pick them up online from Mouser.com