Electronic lock connected via wireless (Wi-Fi) and MQTT using MsgFlo. The lock is intended to enforce 'checking out' and 'checking in' portable tools in a shared workshop environment.
It makes it possible to:
- Know whether a tool is currently in its station
- Checking for neccesary safety course before allowing usage
- Holding people responsible when equipment is not get returned or broken
Each lock has a key with a matching key pattern. The key is physically attached to the tool using a wire. An optical sensor detects that the right key is used. IR leds normally light through, only a matching key will fully block light.
The key and lock can be CNC-milled, lasercut or 3d-printed.
Proof of concept
- July 2017: Functional prototype was built during 2-day hackathon
- First production version planned for October 2017
Bill of Materials
- Microcontroller - ESP8266 or similar. We used a Wemos D1 board.
- actuator - we used a solenoid that is rated for 12V (it actually actuates at about 7V, but slowly), it draws about 0.3 - 0.7 A. Alternatives: 1 2
- mosfet - we used a IPP055N03L
- resistor - a 10k ohm resistor for pulldown on the control signal
- power supply - a 12V DC power supply for the actuator / solenoid
- IR led 0805, 120deg. Kingbright kp-2012f3c
- IR phototransistor 0805, 120 deg. Kingbright kp-2012p3c
- Install Arduino libraries PubsubClient and Msgflo
- Setup wifi connection: Add a file
- Configure MQTT details in the sketch
v1.0: First fabricated version
- Electronics: Switch to a standard transmissive detector, PCB mounted.
- Mechanics: Update to vertical PCB orientation, check connections
- Produce initial 4 locks
- Mechanics: Add a casing/box for 4-8 locks. Securely wall/table mountable.
SIG: gnd+in PWR: 12v+gnd OUT: 12v+out
IN GND 12v 12v OUT