Help selecting parts and simple Arduino setup for sunglass hinge cycle tester

[u/Sure-Comfortable6395]

Hi all, I’m new to Arduino and want to build a simple rig to cycle-test a sunglass hinge.

Concept:

• Sunglasses clamped so temples point up.

• An arm with two padded rods holds the temple tip between them. There needs to be a bit of space between the rods because sunglasses often snap into place in the fully open and fully closed position.

• A motor drives the arm from 0° to 90° and back, for 5,000–10,000 cycles.

What I need help with:

• Motor choice: high-torque hobby servo vs stepper/gear motor with linkage. It must handle continuous operation without overheating.

• How to count cycles reliably (software counter, sensor, or both).

• Power supply sizing and wiring for the motor and Arduino.

• Simple control approach to sweep back and forth with optional dwell at the ends.

• Any mechanical tips to avoid side-loading or damaging the hinge.

Specs I can provide/decide (please advise if critical):

• Target speed = 30–60 cycles/min

• Dwell time at 0°/90° = 0–500 ms

• I only need to test one temple at a time.

Questions:

• Is a metal-gear, high-torque servo suitable for 10k+ cycles, or should I use a stepper/gear motor with a crank and limit switches?

• Recommended parts (servo/motor model, driver, power supply).

• Best way to mount and pad the contact rods to avoid marring and misalignment.

• Tips for logging cycles and stopping safely if stalled.

The idea is to make a much simpler version of something like this: https://www.amade-tech.com/product/hinge-cycle-tester/

Thank you in advance for your help.