[VLM]

Over the last 20-30 years there have been innumerable microcontroller projects involving a stepper motor and a servo and very recently some 3d printed parts to open combo locks. Its an interesting real world project.

At my high school some decades ago we had the 3-turn 0-39 master locks but mfgr sloppiness meant there were really only ten or so possibilities and if you knew the last digit you only had perhaps 100 or so combos to try which doesn't take long.

A frenemy of mine got into a practical joke war and my friends collected tens of thousands of magazine subscription cards from the school library over the course of weeks and filled his locker with them when I finally brute forced the lock. He responded by filling my locker with many thousands of 4-40 sided machine tool nuts and some washers fed in thru the top ventilation slots. Well, it all seemed like a good idea at the time.

Small time barely noteworthy events happened all the time like remove the lock and attach it to the locker upside down, or replace it with a different lock, or swap it with a neighbors lock, or remove and/or change the numbers on the locker door. Oh another move was breaking into a locker, and respectfully not touching any personal property but disassembling the interior of the locker such that the victim no longer had a coat hanging hook.