Trying to use phototransistors to find heat sources and work out where they are, for the brief ‘my robot army will hunt you down’. They seem to be the wrong stuff for a human heat source. I have not yet tried this out, and I should, but I’ve been told they are wrong.

I can do some other stuff, like have an IR source in the middle of the pupil, and then bounce off that, which might work. However, for the moment I’m failing with a 3D printer instead.