It was a thrill for me to see the drawing of Randy Sargent’s Herbie the robot in the illustration to my Mousey the Junkbot article in Make No. 2. I’ve seen other people’s bots that utilize the ingenious Herbie circuit, but I’d never seen Sargent’s original design. While poking around on Solarbotics.net, I found this photovore, built by Grant McKee, that follows Sargent’s original construction.
Click on the image to see a larger version. Another view can be seen on Grant’s Photovore BEAM page.