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

LEGO Critter Cam

My first Raspberry Pi LEGO project was to setup an automated video surveillance of animals in my backyard. This is similar to the project in “High-Tech LEGO,” in which I took high quality still photos of animals. Here, as allowed by Raspberry Pi control, videos are made of animals. To make the video above I attached a 2x8 Technic plate to the side of a squirrel feeder. The plate provides a platform for attachment of a Grove Ultrasonic Ranger ( When a squirrel steps onto the platform of the feeder, a quick video is triggered.

The Raspberry Pi and GrovePi ( are attached to a Smarti Pi Touch ( as described in my post on Raspberry Pi Mindstorms. The display built into the Smarti Pi Touch allows checking on videos while the device is still setup outdoors.

Below are a couple sample results with the LEGO Critter Cam relocated to ground level underneath a bird feeder. Seeds from the feeder fall to the ground, where I noticed rabbits came to eat. Many birds also visit the seeds on the ground, shown in the last video. The video begins with both a male and female cardinal--the female is seen early in the video as she is close to the camera. She later bumps the camera after taking flight. I don’t know the species of the other bird next to the cardinal.