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

Google Doc

• 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

https://wiki.wemos.cc/products:d1:d1_mini https://github.com/esp8266/esp8266-wiki/wiki/Pin-definition

• Install Arduino libraries PubsubClient and Msgflo
• Setup wifi connection: Add a file Config.h defining parameters WIFI_SSID and WIFI_PASSWORD
• 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.

MIT

einsmein, tingox and jonnor

Developed in KiCAD.

Developed in FreeCAD.

SIG: gnd+in PWR: 12v+gnd OUT: 12v+out

IN GND 12v 12v OUT