Let's Make Robots!

windscreen wiper motor with three brushes...

Hi all,

I always thought/assumed that brushed motors had two brushes in them. Mine has three. How does it work?

Cheers

Ycd

Battery charger (method) for lead acid battery

Hi all,

Got my hands on 4 of these babies battery

They were for free so i have to use them:-) Would like to have 12V and as much power as possible so I was thinking of this setup:

batterycharger.jpg

QUESTION 1: can I just charge this whole thing with a suitable chargers as if it is one big 12V 20Ah battery or do I have to do something differently?

Windscreen wiper motor

Hi All,

Got my hands on 4 new windscreen wiper motors for 40 euro in total. Which should get me started with building something nice. The seller told me it is one for a VW Golf which I checked on other sites and they look the same.

Of course I opened it up and it has a couple of metal connections (see picture 'inside') on the gear wheel which connect to wires going to the outside (to make the wipers go left and right I presume. That would make a nice rudimentary odometer don't you think?

My PROBLEM (if it is...) NO SPECS

Outdoor navigation

Hi all,

Modest as I am, the decision has been made to build an outdoor autonomous robot which will mow my lawn. :-D

The environment:
The garden is 50*50 meter (150*150 feet) with the house somewhere in the middle, completely fenced off with a gate. 2/3rd covered by grass in different sections separated by driveway,paths/house/garage. Altitude difference is 6m (18 feet) between lowest and highest point. Maximum slope is 30 degrees (containing grass). Soil, no rocks.