Batteries and motor questions!

[Daddysherky]

Hi, I am new here and was wondering if someone might be able to help me with a question. My robot is homebuilt on wheels. I want to steer the bot with an electric window actuator (from a car) The motor turns much to fast to control so I want to use a PWM to slow it way down. My question is what size PWM do I need.

Here are the specs of what I am using
~Sealed Lead-acid Batteries (12v12ah/20hr) 2 in series)
~Dorman 741-814 window actuator (Just the 12 volt motor!)
~DPDT switch wired for reverse to turn wheels left and right (servo attached to run remotely)

Links to products used:
http://www.energexbatteries.com/product ... B47%7D20hr

http://www.amazon.com/Dorman-741-814-Mo ... B000E347L6

http://www.radioshack.com/product/index ... Id=2062530

Thanks for any advice. Also if you have a better less expensive approch I will take any suggestions.

[MarcoP]

Hi

Look at H bridges http://en.wikipedia.org/wiki/H_bridge
They can do PWM to regulate the motor speed and also reverse the current flow to allow you to switch direction without the need for a DPDT switch.

The main parameter you have to look at is the current required by the dc motor.

Regards