Introduction: Smart BT Door Lock(simple Arduino)

Picture of Smart BT Door Lock(simple Arduino)

This is a simple project made with the arduino uno R3,the aim is to control a door lock without keys,and using a smart phone to accomplish this,the communication medium is Bluetooth thus the working limit is upto 10m,includes PASSWORD for security.

Step 1: Collecting the Items Required

Picture of Collecting the Items Required

1.Arduino UNO R3

to control the servo and interface with the bluetooth module.

Step 2: Bluetooth Module

Picture of Bluetooth Module

to receive signal when to open or close the lock,to know the status of the lock wether open or close

Step 3: High Torque Servo

Picture of High Torque Servo

to turn the lock lever when signal is sent from the arduino

it is powered by the arduino 5v pin itself and it works well with it.

Step 4: Travel Adaptor and UNO Cable

Picture of Travel Adaptor and UNO Cable

this is used to power the arduino,the Servo will not work if the arduino is powered with a HW 9v battery.if you want to use a HW battery to power the arduino then you have to power the Servo separately.

Step 5: Sheet Metal

Picture of Sheet Metal

this is used to make the case for the servo motor which allows it to properly hold the motor on the door and the rotating part properly fixed to the lever of the lock.

the case is upto your creativity you can use any other material/thing to make the case.


Step 6: Coding With IDE

Picture of Coding With IDE

the coding is attached you can download and refer it.

Step 7: Building Own App With App Inventor

Picture of Building Own App With  App Inventor

you can download the app from here,i have also provided the images for building the blocks and designing the app with MIT app inventor.

Step 8: Screenshots of App Inventor

Picture of Screenshots  of App Inventor

refer images.

Step 9: Assembly

Picture of Assembly

after connecting the bluetooth module then connect the servo ,

SERVO CONNECTION pin 2 pin in arduino

3.brown------ground pin in arduino


1.I have set the password as home \ can change the password by changing the global variable text in app inventor blocks screen 0.

assemble all your things and upload the coding to the arduino board and download the app on your phone.

TEST YOUR PROJECT good luck!!!

Step 10: Final Look

Picture of Final Look

Step 11: Servo Attachment

Picture of Servo Attachment


LuisD43 (author)2017-10-26

Can be controlled by WI-FI?


einzigartig arun (author)LuisD432017-11-03

refer my new instructable by clicking here!

lukee1986 (author)2017-10-19

sounds nice and cheap compared to some ive seen great work needs alot of tiding up before it makes mainstream

Swansong (author)2017-10-18

That would be really convienient, especially if you're carrying stuff in :)

About This Instructable



Bio: I like to do robotics and automation projects.* denke anders!(think different)
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