Motor for clock seconds hand


I am looking to build a clock controlled by my Arduino Mega with a motor driven seconds hand which can keep accurate time and be adjusted in response to inputs during operation. I attempted this with a 360 degree continuous motion servo with no success as I need to be able to drive the seconds hand to different locations upon new time settings during operation. I need some kind of feedback loop so the motor knows where the hand is at any given time and can be driven to a specific location.

I thought about using a stepper motor and counting the steps to keep track of position however as I am displaying seconds I need to make 60 even steps of 6 degrees in one revolution. So with the standard 200 step/rev stepper motor this would mean I would need to program it to take 3 and 1/3 steps per second and I don’t believe this is really possible as steppers seem to only be able to do full, half, quarter and eighth steps through their drivers.

Is there some kind of encoder available that will allow me to use a stepper to make 60 even 6 degree steps per revolution and keep track of the motors location?

Or is there another type of motor, controller and encoder maybe that is more appropriate?

Any help would be great.


Hi Lawrence,
It’s a tricky one, as you mentioned, for a clock, it requires precise, angular rotation. Perhaps the best place to start would be with a standard motor encoder which uses a hall effect sensor to keep track of the motor rotation. Combine that with a full directional H bridge motor driver which allows you to brake as well as move so that you can stop precisely.

Hi Sam,

Thanks for that, I’ll give it a go. Can you recommend a suitable motor, encoder and H bridge driver?

Hi Lawrence,

It’s hard to recommend a particular product without knowing more about your project. For example, the current and voltage specs for your motor will determine the appropriate driver. The size of your motor and shaft for the encoder. Perhaps do a search around for those particular products, read up on them, and find one that will suit your project.