Stepper Motor vs Continuous Servo to Open / Close Cat Door?

I have the laziest cats in the world. They haven’t been able to figure out how to push open their pet door. So I thought, why not use the Photon for me to open it for them?

I was thinking I’d attach a string or cable above the cat door to pull up and open the door. I could also send another command to let the door close back to.

The pet door is extremely light and I wouldn’t expect it to require much torque to open the door.

I’m new in the world of hardware electronics, so I’m not sure if I need a Stepper Motor or a Continuous Servo.

If it was Continuous, then I’d have to time how long the spin the motor until the door was all the way open.

If it was a Stepper, I could figure out how many revolutions would be required until the door was in the full open position.

If you have such experience, could you share which type of hardware application you went with and can you recommend such hardware?

Thanks for the suggestions.


I’m would think a simple servo would be the smallest and best way to go for simply opening that cat door.

Check out if you have not. I’m sure they have something you can use.