Motor shields questions

Hello

I am planning on buying arduino motor shield (A000079 Motor Shield Interface) but before I buy it I had a few questions. I am planning on building a wifi controlled car. I am planning on stacking a wifi shield on top of the Arduino uno r3 then stack the motor shield on top the wifi shield. Questions:

Can I attach a ultrasonic sensor, 5 volt servo motor, and stepper motor to the motor shield?
I know you can attach sensor to the Arduino Uno and wifi sheild. So I was wondering does the motor shield have the same pins as arduino uno and wifi shield?
Do I need to attach a battery to the motor shield to control a stepper motor?

  1. Yes, depending on which shield you buy. I expect you've already found one that can control servos and steppers but you're keeping it secret for now.

  2. Not all shields use the latest R3 layout, which means they don't have exactly the same pins. This is unlikely to be a significant problem for your setup, although an I2C sensor may need those pins if you're not using an UNO as the bottom of the stack. (you didn't tell us which Arduino you have)

  3. Yes. The motors must be powered with a beefy power supply that can deliver enough volts and amps for the (unspecified) motor.

I am planning on buying arduino motor shield

What one?

So I was wondering does the motor shield have the same pins as arduino uno and wifi shield?

It depends on the motor shield.

Can I attach a ultrasonic sensor, servo motor,

No you attach them to pins on the Arduino

and stepper motor to the motor shield?

You can connect that to the motor shield providing it is the right one. Normally motor shields are for DC motors not stepping motors despite what the advertising may say.

Do I need to attach a battery to the motor shield to control a stepper motor?

Yes, otherwise where is the power coming from?