Re: [mowbot] RFD: Define reference 'grassbox' for mowbot development.

byron nospam at
Tue May 12 17:49:49 EDT 1998

> ---Byron A Jeff <byron nospam at> wrote:
> >
> > the discussion has centered around sensors, mapping, and boundary
> detection
> > (Which I believe are solvable problems) where I'm confused is the
> pure basics:
> > How to get a mobile platform that cuts grass.
> Mobile platform is much easier problem than that of its control. The
> former can be easily solved using state of the art in mechanics and
> electronics, full solution to the later exceeds current state of the
> art.

See?! the discussion has started already.

My problem is that I'm definitely not up to state of the art in mechanics.
I think that's my bias. As a computer scientist I always think I can solve
the sensor/mapping/etc problems if I could just get the platform together.

Where can I learn about servicable motor, gears, drivetrains, etc?

> > Of course finding a powerful enough motor is another > problem.
> I bought bunch of 12V 15000rpm at 3.6A motors from American Science &
> Surplus for $7.50 each, they seem to be perfect for trimmer / disc
> with blades application.

Excellent! Are they on the web? Will check just as soon as I finish this

Any suggestions for drive motors? Preferably a pair that I could mount
on a platform and directly attach lawn mower wheels to?

> >I want to
> > thank Paul for posting that motor driver board a while back. BTW is
> that
> > a kit or is it fully assembled?
> Its fully assembled and weather resistant.

Even better. I think I'll be picking up one soon...

> > Can't steering simply be done by having
> > centered, bi-directional drive motors?
> Why not by rear, bi-directional drive motors?

I thought those were more difficult because the drive motors are then
not on the center axis, making it difficult to perform maneuvers such as
spinning on place to turn and having precise control of the nose of the
vehicle. That's why I thought Ross was looking at a steerable rack on
the opposite end of the machine.

I cliam ignorance. Please feel free to enlighten me on the subject.