The purpose of this innovation is to provide increased security for classrooms. This lock utilizes a mechanism that will allow for only one authorized person to allow or deny access to a classroom, said authorized person typically being a teacher or administrator. The assembly consists of an electromagnet powered by a motor driver, which is controlled by a micro-controller. The micro-controller's code unlocks the door in the presence of an NFC tag. An adjustable timer allows for a delay in re-locking the door.
Step 1: Parts List
Step 2: Electronics
1. Mount NFC shield to Arduino
2. Pin 11 to data wire on motor driver
3. 5V pin and GND to respective ports on motor driver
4. Connect 9-volt supply to motor driver.
5. Connect electromagnet leads to motor input on motor driver. (In my case, M1A and M1B)
6. Connect Arduino to a computer and upload the provided code.
Step 3: CODE
The following code will be used to run the IN-STOP electronic closing mechanism.