Let's Make Robots!

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?

Has anyone tried the X2 chips yet?

I just ordered a couple 28X2 chips for my porch gardening project, and the changes they listed in the info was sort of confusing.

I'm just wondering if any of you guys out there have tried them yet, and have any comments/gripes/tips/tricks about the newer chips.

I really wanted to try out the 28X2 module they made to compete with the Basic stamp, but I'm poor.

-Z

DC motor question

I was walking through Lowes the other day, and found this great trash can that looked like a robot to me. I was able to pick it up for super cheap!! What I want to do is add two DC motors to the bottom and a caster wheel. I want to make this robot carry my books around school for me. I am lugging more text book weight than I ever did in the Army with my ruck sac. My physics book alone is killer.

Trash Can

Ping))) or SRF05?

I would like to get some sonar sensors, but I cannot decide if I should get the parallax PING))) or the SRF05?

 

Which one to pick?

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

Large res LMR banners and pictures?

Hey LMR'ers have you found any high res/large LMR banners, pictures, logos? Im looking for some big ones so I dont have to resize the tiny ones.

Thanks

360 Range Finder

I just received my SRF05 and I can't wait to start using it.  While I was thinking about it, it occurred to me that I always see the SRF05 mounted on a servo, which allows maybe a 180 degree field of view for a robot. I wondered if anyone ever mounted a range finding sensor on a motor so a robot could see in every direction. 

I think I may try to build a 360 degree range finder, but I wanted to open this as a topic and get some ideas. Here's what I'm planning. Let me know what you think.

Hardware

I was wondering...

Can you controll an electromagnet with a PICAXE?

if so how?

Many thanx in advance :)

Controlling a DC Motor (Mabuchi FA-130)

Hello,

I'm trying to run a Mabuchi FA-130 (#18100) DC Motor, it uses 3V and 2.1A when stalled. However, I did some measures and when I forced the motor to stall it consumed nearly 4A, but I think this was some sort of coincidence since It has never happened again.

I'm using a circuit similar to this one posted by Simon Z in his post:

simple_dc_motor_sch.jpg

(By Simon Z and taken from http://letsmakerobots.com/node/7990)