Network Connected Lock

by GuyChernobrov, published

Network Connected Lock by GuyChernobrov Jan 10, 2016
0 Share
Download All Files

Thing Apps Enabled

Order This Printed View All Apps

Design Tools



Use This Project

Give a Shout Out

If you print this Thing and display it in public proudly give attribution by printing and displaying this tag.

Print Thing Tag

Thing Statistics

2504Views 390Downloads Found in Engineering


This is a mechanism designed to lock and unlock a door by mechanically turning the lock cylinder using a servo motor controlled by an Arduino. By using a wireless Arduino shield the door can be locked and unlocked remotely from a mobile phone app. In this prototype I’ve used the SmartThings Arduino shield for the network connectivity (it connects to a SmartThings hub using a Zigbee network). The mechanics is based on the Worm Gear Reducer, published by Mattheus (https://www.thingiverse.com/thing:41161).
This is a first prototype. It uses a simple (and cheap) HS-311 servo motor, converted into a continuous rotation servo. The mechanics is simple and reliable and it provides enough torque to turn the lock, by using the reducer. The mechanism is rather slow (a full turn of the key takes more than a minute). This design trades torque for speed. This way it is able to turn the lock using a small and relatively weak servo motor which doesn’t require much current and it can be driven directly by the Arduino. The prototype is powered by a portable USB charger.
The model was designed using Sketchup. Here is a link to the Sketchup files on 3D Warehouse, so the design can be modified (e.g. to fit other types of locks). https://3dwarehouse.sketchup.com/model.html?id=u49c8e7b9-ba90-4d48-9280-3fb5b7a23cf7

Print Settings

Printer Brand:



Prusa I3








20%, 40%


The assembled mechanism

Assembly and Setup

I used ABS for all the printed parts. The worm gear is printed with 40% fill. All the other parts are printed with 20% fill. The layer thickness is 0.2mm for all the parts.

Bill of Materials:
Arduino Board (I used Arduino Mega, but any will do)
SmartThings Arduino Shield (or any other wireless connectivity shield)
HS-311 Servo motor
A portable USB charger
Pushbuttons X2 (for local lock/unlock without using the mobile app)
M3X50 screw
M3X30 screws X3
M3X20 screws X4
M3X10 screws X2
M3X5 screws X4
M3 nuts X6
Double sided adhesive tape
Some wire for connections (22 AWG)
The printed servo adapter must fit tightly on the servo motor shaft. To get the exact diameter you may need to use a 5.5mm drill. Once you get the right diameter you should tighten the adapter to the servo shaft using two m3X5 screws.
The servo motor should be modified to a continuous rotation servo (here’s how: https://www.flickr.com/photos/randomskk/2569969633).
In the Arduino sketch there are parameters to control the rotation time, speed and angle. These parameters should be adjusted to your specific lock cylinder.

More from Engineering

view more

All Apps

3D Print your file with 3D Hubs, the world’s largest online marketplace for 3D printing services.

App Info Launch App

Auto-magically prepare your 3D models for 3D printing. A cloud based 3D models Preparing and Healing solution for 3D Printing, MakePrintable provides features for model repairing, wall thickness...

App Info Launch App

Kiri:Moto is an integrated cloud-based slicer and tool-path generator for 3D Printing, CAM / CNC and Laser cutting. *** 3D printing mode provides model slicing and GCode output using built-in...

App Info Launch App
KiriMoto Thing App

With 3D Slash, you can edit 3d models like a stonecutter. A unique interface: as fun as a building game! The perfect tool for non-designers and children to create in 3D.

App Info Launch App

Print through a distributed network of 3D printing enthusiasts from across the US, at a fraction of the cost of the competitors. We want to change the world for the better through technology, an...

App Info Launch App

Quickly Scale, Mirror or Cut your 3D Models

App Info Launch App

3D Print a wide range of designs with Treatstock. Easy to use tools to get the perfect result. The global 3D printing network that connects you with high-quality and fast working print services nea...

App Info Launch App

Internet of Threats