Re: Roomba 570 problems

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Dan Lanciani" <ddl@danlan.*com> wrote in message
news:1347996@xxxxxxxxxxxxxxxxxxxxxx
> I decided it was finally time to try a Roomba so I got a 570 from
> Hammacher Schlemmer.  It worked for about an hour total and then
> one of the wheel modules seemed to lose the ability to move in a
> forward direction.  This made the Roomba turn in a tight circle
> until it gave up.  There was nothing obviously mechanically wrong
> with the wheel module (it turned freely by hand) and when the Roomba
> tried to turn it the wheel did stiffen up (as determined by my hand).
> Maybe part of a bridge driver had failed?  Anyway, Hammacher Schlemmer
> exchanged the whole package for a new one.

FWIW, in reading up on your unit this weekend, it seems there is a tendency
for hairs, especially long ones, to wrap themselves tightly around the brush
and wheel shafts and trigger the motor stall sensors.   I've had that happen
with the drive wheel but it seems if the wheel turns freely, that's probably
not the problem.  It apparently takes very little torque difference in the
two drive motors to make big turns.

If you put the unit on a table ledge so the cliff sensors sense "solid
land," you can put a wheel in each palm and guesstimate the torque.  When it
starts up, it should alternate between wheels pretty forcefully in your
hands.  You have to keep the wheels pushed up into the body of the bot with
your hands to keep it from shutting down.

http://forums.irobot.com/irobothome/board/message?board.id=80&thread.id=2389
&view=by_date_ascending&page=2

talks about brush problems.  Do you have two different size roller brushes
and are they bristle or rubber paddlewheel style with four vanes?  It seems
that iRobot replaces bristle brushes with rubber flapped ones when owners
complain.  The Red 4300 comes with a small rubber roller and a larger
bristle one.

One of the tests they had me run when mine began spiraling was to run the
unit without any brushes at all.

I've gathered that a lot of problems surface in the first few runs of new
ownership due to the typically high initial "dirt load" in the house.  No
matter how anyone vacuums, the Roomba will still outdo them, covering the
same area many times and getting under beds and bureaus where it's really
hard to vacuum.  After these initial "deep grunge" runs, things settle down
a bit if they haven't failed.  It's an almost universal observation of
Roomba and Scooba users that both get dirt that most other methods don't.
New users in the iRobot forums are encouraged to manually clean the best
they can and then to see how much more dirt the Roomba finds.

Let us know what happens.

I've built a fairly primitive but useful small brush cleaner by cutting
radial slits in a plastic milk bottle cap.  When you push the brush back and
forth through the gores they spread apart and the tips dig into the dirt and
a lot of it falls into the bottle below.  Great for scraping off all the
hair and grunge, but strong threads wrapped around multiple times still have
to be cut with the Roomba letter opener tool.  Still, the less roller I
touch with my hands, the happier I am.  I have a repair ticket in with them
now and I'll ask them if the rubber paddle wheel brush is going to replace
the small bristle brush on future models or just the vacuum type bots.

Tonight's project is to mount rechargeable NiMH batteries in the Roomba
Virtual Fence and build a base station that recharges it when I am finished
using it.

--
Bobby G.