This video demonstrates the “Presence Detection System” concept. This project uses a pair of Bluetooth modules which is HC-05 (master) and HC-06 (slave), a USB to UART converter to connect the BT modules to the computer and a relay module for building up application circuit.
The BT modules need to be set up with certain configuration to make them automatically connect between each other when they are visible to one another. This project does not use any Arduino and its code at all. However, we still use it’s Serial Monitor to help setting up the BT modules in the AT mode.
You may implement this kind of “presence detection” concept in your own projects namely the key-less entry for vehicle, automatic gate opener for home application or the child surveillance system for the safety of your kids. You name it, the sky is the only limit.
If you wish to add up some timer or kind of intelligence to your project, then use micro-controllers such as PIC or the Arduino. All
you have to do is just monitor the “STATE” pin of the HC-05 BT module, which will give about 3.3V when it is linked to other BT device or 0V when it is not. To let say build a forward/reverse motor control circuit, refer my other videos on my channel. Feel free to ask me questions in the comment section below.
Joakim Karud’s collection on https://www.theartistunion.com/
1. Wish You Were Here
2. Hate It Or Love It
Credit to Martyn Currey (http://www.martyncurrey.com/) for the guide on auto-pairing of the BT modules.