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Power requirement for arduino with 4 servos? Answered

Right now I have an arduino (power being supplied by a 9v battery) controlling 4 servos (using 4 digital pins). The servos are connected to a breadboard and are acquiring power from four AA batteries (essentially a 6v battery).

However, I cannot figure out how much current the motors are drawing, nor how long these batteries will last. I don't know if the robot I'm building should use AA, C, or D batteries.

The image is a rough representation of what I have right now (except the four batteries I have are all in one pack).

Any help would be greatly appreciated!



2 years ago

There is lots of chatter and theorizing out there on amp draw of servos. I thought this was a nice write-up of testing servos with the equipment needed, right down to the connectors. And there aren’t any exotic parts. Imagine being able to answer a spec question on your servos with “Because I tested it.”


Also, battery life will be dependent on if the servos are mostly idle or if they are being flogged at their maximum. If you watch BattleBots, or the like, they are always going on about the batteries in the really fast Bots. Push the servos and drain the battery.

Like iceng says, go big initially and you can always go smaller as you figure it out.


2 years ago

Start with [C] cell batteries thereby ensuring room for [AA] later should you discover software does not overwokr your servos.