Lego Sherlock Holmes figure focuses a light beam on a Lego criminal with a small magnifying glass.

LEGO Lidar Part 3: Scanning for Intruders

sector scan through 120-degrees.

The LIDAR-Lite v3 has interesting applications in security monitoring. By scanning the lidar beam a wide area can be monitored to not only detect an intruder, but also determine the intruder’s location. As a demonstration, I used the scanning setup showed in my post “LEGO Lidar” with the software interface in my other post “LEGO Lidar Part 2: I2C Interface.” I scanned a section of my backyard, which as seen in the photo below, has many features of bushes, trees, and structures. In the image above are two scans: 1) a background scan (green dots) showing ordinary features of the yard and 2) a later scan detecting an object not normally in the yard. The lidar beam is scanned in this example through 120-degrees of angle in 1-degree increments. A faster scan could be used to detect quick moving intruders, by scanning only a few look angles. Further refinement could be made to track an intruder once it’s discovered.

photo of scanned area.