Re: [mowbot] Motors arrive

Byron A Jeff (byron nospam at
Thu, 6 Mar 1997 11:41:36 -0500 (EST)

> > Any updates on cutting technology? Anyone consider simply using a real
> > lawn mower attached to a base such as above. Real lawn mowers definitely
> > have the correct cutting technology, they just don't have the correct
> > platform for autonomous (sp) motion.
> I'm a little slow today. By "real" mower I guess you mean,
> gas powered bladed; At first I thought you meant "reel" mower;
> the old style push mower.

I did mean gas powered blades. And yes I understand the safety hazards.
But it seems we are in a catch 22 situation when it comes to cutting
technology: every effective cutting method it too dangerous or power consuming
to automate.

Well let's try to break that chain. For safety we need some way to start and
stop the motor instantly. How can we do that?:

1) Electric powered blades.
2) Gas powered blades with a clutch - which standard lawn mowers do not have.

For good cutting we need real power. Our options:

1) Extremely frequent power stops. Not necessarilry a bad thing if we are
totally automated.
2) Higher density power. In other words gas.

So in comparison we should examine the most available, most used, best
engineered self-contained gas/electric system in existence: the automobile.

It solves the problem by selected option 2) in both instances. The electrical
system essentially just drives the electronics and the starter. The clutch
can engage and disengage the motor from the drive system.

But there are other options:

1) Use a gas motor to drive an electric generator and use the generator to
drive a completely electronic subsystem. The motor/generator is a solved
problem: go to the Hardware superstore and get a generator.

2) Use a gas motor to drive the blades with an electronically controlled

3) Use an all electronic drive system and make the frequent pit stops.

All I know is that I'm desperate to find a drive/cutting technology that's
effective yet safe.

> I "tested" a reel mower by connecting it to my son's
> "bigfoot" battery car. It worked - sort of -
> The biggest problem I guess is that it needs to keep
> some real rotational momentum going to cut well.
> meaning long stretches, moderately high speeds -
> does very poorly stop and go tight corners etc.

OK how about helping the reel mower by driving the reel with a separate
electric motor? That way the speed of reel rotation need not be connected
to the speed of the platform.

> >
> > Comments and criticisms welcome. Put it right back here on the mailing list
> > so we can bounce it around.
> I think in general an automated gas powered mower is considered
> too dangerous. (Think kids, neighbors, pets, etc.)

Agreed. But I'm looking for a solution to work from, and soon. My hope that
the list was generate feasible ideas for moving and cutting during the
winter time here so that I could have a non-automated platform to experiment
with in the spring. Like I said in my first post, it's been 80 degrees lately
and raining. The grass is sprouting and the technology is dormant ;-(
The prospect of having to cut by hand is depressing.