Designed and built an eddy current braking system using a motor-driven aluminum disk, Hall sensor, and adjustable magnetic field. I measured rotational deceleration times up to 2400 RPM and compared braked and unbraked conditions to isolate eddy current forces from mechanical friction, observing that electromagnetic drag force accounted for ~92% of the opposing force at high RPM. By using this force, I was able to infer an effective magnetic field strength of ~0.07 T acting on the disk.
Key Challenge: Expected eddy current drag to scale with velocity, but measurements showed nearly constant stopping time at higher RPM.
Resolving this required that I separate mechanical friction from the electromagnetic effects, revealing that eddy current forces dominated only above a threshold speed.