bodkin77:
Looks like I'm being told. Do you mean for all servos and all Arduinos? I just have 1 9g servo, 2 LEDs and 1 PIR sensor. The circuit works for the nano but not for the pro mini. I'm wondering why not because they both use the ATMEGA328 chip. Note that I removed the regulator on the pro mini. I thought the nano was the same thing as the pro mini except for the USB port, making the nano able to pass less current from external components because the USB port requires some current. I was hoping to use the mini so that the sleep mode uses less current due to the lack of USB port.
When you modify a board, you will (unpredictably) change the operation of that board, so bear that in mind when looking for the problem. Also, what's with the two power switches? If all eight of your double A's deplete at the same rate, it will make changing them easier.
If you use a second set of batteries to supply power to the motors (the blue wires in your diagram) and connect the grounds (black lines) between both sets of batteries, your motors should work as expected with most (properly powered) microcontroller boards