Powering the Robot

Hey guys. I have a question about supplying power to an arduino obstacle avoiding robot.

  1. Lets say, I have a arduino and the motor shield, thats puts on the arduino itself. Do I need to connect the batteries just to the arduino? Or I have to have separate power supplies for the arduino and the motor driver?
  2. Whats the best type or battery to use for this kind of project? Im thinking of going with a 8.4V 200mAh Ni-Mh battery and maybe buy a charger for it

Motors generate a lot of electrical noise, which can cause damage or reset an Arduino. It is usually best to have separate power supplies for the Arduino and the motors.

The size of the battery you need is determined by the average current consumption of the robot and how long you want it to operate for one charge. A 200 mAh battery is very small.

And the batteries for the motor driver and the arduino should be the same, or it can be different?

Motor batteries are usually far larger than the Arduino battery.

I have another question. I have a toy chasis that already has a battery slot in it for powering it(think its 6xAA batteries). So, I suppose i could use that for powering the motor itself, and add another for the Arduino?