Motor size Q from novice

Hello i recently purchased an arduino and have been playn around with turials online. My end goal is to control 4-5 motors that can lift around 30 lb (speed is not a factor). It must be able to reverse and be able to rotate a set number of times.

It will be used to raise/lower curtains.

I never knew that so many types of motors existed! Which one should I use and why? Will I need an h-bridge or motor shield? How many arduinos will be required?

Any help is greatly appreciated

-thundder

Clarification: each motor will be lifting 30 lb

Probably your best bet is gear motors . Straight bi-polar go to fast.
I think that gear motors might be best because they step up the torque, and they probably will not require a locking mechanism to keep the curtains up. With an H bridge, you can control up/down and adjust the height by applying current for set amounts of time.

Google "gear motor" and you will get all the info you need as per amperage, rpm etc...

Hi,

Think about automobile window motors; they are gear motors and often available at low cost.

If these are not moving very often, relays would be the easy way to do this, along with limit switches or position-sensing switches. Most relay boards have Single-pole Double-Throw (Form C) contacts so two relays can start, stop and reverse a motor.

Some Arduino Power How-to Here: http://arduino-info.wikispaces.com/ArduinoPower

How many curtains, how far apart?

If you're raising/lowering curtains, using gearmotors is a good option, but whatever motor you decide on, take the strain off the motor: Use counterweights (like they do with stage curtains - depending on the size of your system, you could either use real weights, or springs, or bungee cords, or something else) to allow the motor to easily raise and lower the curtains.

Thanks for the help guys, I appreciate it!

The cutains will be spaced closely but there will be corners in between some of them. This is why i thought several smaller motors would be the best option.

As for the car power window motors-that seems to be a great idea and the prices are right on ebay. However, is there a convenient way to find out how much torque these motors put out? I think finding their data sheets might be hard/impossible.