Passive Infrared Webcam Tracker

From the “My Electronics Notepad” blog, Noel Portugal created a tracking webcam using passive infrared (PIR) sensors, a webcam mounted on a servo, and the IO-204 monitor and control module.

PIR Sensors, Webcam, and ioBridge IO-204 Module

PIR Sensors, Webcam, and ioBridge IO-204 Module

Noel was able to pull this off with using the ioBridge Actions. An action is logic created through the ioBridge interface that allows automated events to occur. For example, an action can cause a servo to move to preset position, send an email, update your Facebook status, etc. In Noel’s case, he use the output of the PIR sensor to cause the servo to move to a set position. The output of the PIR is digital – “high” means motion detected and “low” means no motion.

Using two PIRs covering two regions, he was able to detect motion in two regions. If motion is sensed in one area, the webcam points in that direction and if motion is detected in the other area, the servo moves the camera to cover the other region. Very clever.

Here is a video of the webcam tracking in action:

The PIR sensor has been the subject of a recent Adafruit tutorial – it’s available on the Adafruit store and even your local Radio Shack (of all places). For more information about this ioBridge project and other projects Noel dreams up, visit his blog.


  1. I have extended my project to a security system. 🙂

    Check my blog for the details