July 28, 2021

Avoid an Embarrassing Situation at Your Next Zoom Meeting with This Presence Sensing Webcam

from hackster.io

The inspiration...
The COVID-19 pandemic has caused many meetings to go entirely online, which is great for ease of use, flexibility, and the ability to talk from anywhere in the world. However, those wishing to leave early might not remember to turn off their cameras and microphones, thus leading to potentially embarrassing situations. In response to this problem, maker Charitha Jayaweera on Hackaday built a device he calls the "Present!".

The Present! is a small device that clips onto the top of a webcam or monitor and senses if the user is present. If there is no one there, it sends a signal over USB after a short amount of time that causes both the webcam and microphone to get switched off on Zoom.

Designing the device...
The Present! was modeled primarily for 3D printing. The main box houses the electronics, including the Arduino Nano board and HC-SR501 passive infrared (PIR) sensor for detecting IR-emitting sources, such as people, in front.

Possibly the most difficult part of the Present! to design was the mount for holding it on laptops. Jayaweera modeled an arch-shaped clip that slightly bends and slides over the screen.

Fabrication...
Jayaweera took his design and immediately printed it out in PLA filament. From there, he did some light finishing work to clean up the parts and then slotted a few screws to hold everything together. Once the Arduino Nano and PIR module had been wired, it was time to load some code.

Turning off the camera
The program for the Present! is a simple Python script that shows up as a tkinter GUI application.

Essentially, it creates a second thread apart from the main GUI thread that continually monitors the connected serial port. If the Nano has sent the "No person present" command, the Python script will switch the webcam and microphone off.