Powering Two Continous Servos

Hey, I have a BOE bot chassis with an Arduino mounted ontop. I have two high speed continuous servos for the wheels and an 4 pin ultrasonic sensor. For power I have 4 AA batteries powering the arduino.... this does not work very well, the four AA bateries do not supply enough power. So I thought that I could power the two servos with the 4AA batteries and a seperate 9 volt battery simply for the arduino and the 5v ultrasonic. But I hear that the power of the servos must be 'regulated' how can this be achieved? how do you regulate the power? I have limited space on board the chasis and so hope that the need for resistors and or other transistors is not needed. Thanks!

Heres the specifications on the Servos and ultrasonic,

http://www.parallax.com/sites/default/files/downloads/900-00025-High-Speed-CR-Servo-Guide-v1.0.pdf

http://dx.com/p/hy-srf05-ultrasonic-distance-measuring-sensor-module-for-arduino-147397?tc=USD&gclid=COO8gIrZxLwCFQvxOgodmHUAmg#.Uvpq4lNEzR4

But I hear that the power of the servos must be ‘regulated’ how can this be achieved? how do you regulate the power? I have limited space on board the chasis and so hope that the need for resistors and or other transistors is not needed. Thanks!

Servo’s do not require tight regulation of voltage, just that their voltage remain within 4.8 to 6.0vdc or so at the maximum current being drawn by the servos. What is probably required at very good fresh AA cells and even then they won’t last too long if the servos are drawing near max current continuously.

Thanks for your quick reply! Ill go test it now. :)

A related question, if the servos are connected to the batteries, will it draw power from them, even when the arduino is not powered, or is powered, but there is no signal for the servos to run?

Should I add an on off switch to power the servos to prevent using up the batteries?

fredii: A related question, if the servos are connected to the batteries, will it draw power from them, even when the arduino is not powered, or is powered, but there is no signal for the servos to run? That's not a good mode to run a servo as they are not designed to be powered up but with no control signal, which is what you get if you detach the servo in your sketch. However no damage or danger for the servo. As far as current draw, it's directly related to if the motor is running or not and how much mechanical load is attached to the servo, that is where the big current demand is. At idle a servo may only consume 10 ma or less. Should I add an on off switch to power the servos to prevent using up the batteries?