Newbee- choice of motors + motor shield needed

Hello, My name is Bram, and I'm totally new to Arduino. So I've been doing some research for the past few days. So now I have a question: what servo's do I need? The project I have in mind: first decode IRremote like this: http://www.instructables.com/id/The-Easiest-Way-to-Use-Any-IR-Remote-with-Ardiuno/?ALLSTEPS Then I want to do stuff with that remote. Firstly I'd like to buy a simple robot (self driving with sensor or controlled by IRremote). So I would need 2 continuous retation servo's for that I guess? And do I need a motor shield to do this? How can I plu gan external battery to the motors? I read that you can link the + of the motors to a 9V battery, the controll to the Arduino, and the - to the ground of the Arduino. But then you don't have any circulation of your battery...

But I would also like to have a controllable motor. I guess something like this should do it then: http://www.aliexpress.com/item/New-SG90-9G-Micro-Mini-Servos-Horns-For-Helicoper-Airplane/745552837.html?

So... My questions resumed: - Do I need a motor shield to controll 2 continious rotation servo's / 180° servo. - How can I hook up a battery to the motors? - How is it possible thatI can feed my Arduino by a hacked USB cable with a 9V battery, when Arduino is actually made for 5V (usb). - Is this motor controllable with pe a potentiometer: http://www.aliexpress.com/item/New-SG90-9G-Micro-Mini-Servos-Horns-For-Helicoper-Airplane/745552837.html?

Thank you so much for your help! If there is already an existing topic about one of the subjects, you can refer me to it. I hope I will be able to help others within some time....

You mention motors, but then include a link to a servo (not a continuous rotation one either).

Do you want a motor or a continuous rotation servo? The later just need the Servo library, motors need a motor driver board or shield.

You will not have much joy using a miniature 9V battery to power a motor, they need more current than they can comfortably supply.

Nearly all hobby servos need 4.8V to 6V, and small one's can take peaks of 0.5 to 1A, larger ones corresponding more.

Hi MarkT, thanks for your answer!

You mention motors, but then include a link to a servo (not a continuous rotation one either).

With a continious rotation servo, I was talking about a servo like this one: http://www.aliexpress.com/item/2pcs-38g-S3003-Standard-Servo-For-RC-Futaba-HPI-Tamiya-Kyosho-Duratrax-GS-racing-Car-truch/1570774224.html .

Do you want a motor or a continuous rotation servo? The later just need the Servo library, motors need a motor driver board or shield.

Ok, thanks. Then I'll buy a motor shield to get started. Edit: I just read that the motor shield is meant to connect an external power. So I can mybe attach a 4x aa battery pack to reach 6 volts?

You will not have much joy using a miniature 9V battery to power a motor, they need more current than they can comfortably supply.

Can you recommand a battery to juice the 2 continious rotation servo's? Or could I strip an iPhone cable and get a 5v source for a motor? Mybe 1 cable each, or just put them in parallel to get the same voltage? I don't know a lot of all this stuff :0

Thanks a lot again. I'm a bit unconfortable that you have to put your time in me... The only thing that I can do in return, is answering questions about Belgium if yu're interested since my programming/elektronic skills are not very great.