This Clever Lockbox Only Opens If You Solve Its Twisty, Turny Puzzle
Built as a gift for a ninth birthday, the box uses an Arduino Micro compatible and gyroscope sensor to track movements.
Pseudonymous maker "SeeNoFutur3," hereafter simply "Future," has presented his daughter with a gift — hidden inside a wooden box unlockable only by solving a gyroscopic puzzle.
"I made a riddle for my daughter," Future explains of the project. "She has to find the right combination of tilts and turns for the box to open. Progress is visualized with a LED ring that shines through the wood. A reed switch is implemented for programming mode. You hold a magnet on one edge of the box and switch it on. Box unlocks and led ring gets blue. You remove the magnet and tilt and turn the box how you like it. It's saved in EEPROM. When you hold the magnet on the edge again programming is finished."
The wooden box itself is crafted via CNC from mango wood, with the cutout for the LED ring being just 0.2mm in thickness — making it look solid from the outside, but allowing the LEDs to shine through once activated. Inside is a custom circuit board and battery, hosting an Arduino Micro-compatible microcontroller and a gyroscopic sensor. Tilt the box the right way, and an LED lights up; get it wrong and all LEDs go dark. Solve the 16-step puzzle in its entirety, and a servo pops the box open.
"It will be filled with glitter and some tickets for an overnighter in a treehouse with her best friend (and us)," Future says of the gift to go inside the box. "The whole journey to the treehouse will be a riddle and directly at the spot she also has to solve puzzles. I hope it will be a fun day for her."
More details are available in Future's Reddit post.