The NFC module is connected to an Arduino Nano. The walls of the box were a little too thick for the reader to detect the ring, so had to scratch the wall thickness down a bit. used a ring with a built-in NFC tag, similar to the ring featured back in March. If you are going to have a locked box, then you are also going to need a key to open it. When the servo is rotated in the opposite direction, the latch closes and locks the box once again. When the servo rotates in one direction, it pulls the string and releases the latch. The latch is connected to a servo with string. To keep the box locked, he installed a simple latch on the inside.
This kept the cost down but would also allow him to easily decorate the box later on using a wood burning tool. Wanted to build a lock box that would lock from the inside. He started with an inexpensive, plain wooden box.
