I work, primarily in a laboratory environment. Years ago, before digital stuff, I built this box that would measure two changing parameters. When they reach a certain point, I would be told. As I messed with it, I hooked a bell to ring when I was at this point.
One day, our secretary came and asked: "why does that bell go off every time I come in here?" I must have blushed. "Why are you blushing?"
"Its an erection detector, right now it is hooked up to Richard". I had seen that she would look at Richard with a sort of hungry look. Anyway, she went right over to Richard and took a handful of him and the two left. It was near end of shift anyway. I made and sold three of these boxes.
Now, I still work in a lab. but I use computers. I mostly use a program for the analysis of spectrum's. This information is used to check for, anticipate and even predict when things would fail. In this case, aircraft, missiles and space craft.
I remembered the old box and decided to improve on it. My goals now were much higher than a simple erection (pardon the pun). Also, as a diabetic, I check my blood. Now there is a device where you don't need to draw blood. It can read through the shin. I began putting these together, also with an infra-red device to read temperature. I made a parabolic dish so I could "read" people that would just walk by ( at Starbucks)
I got a lot of stuff, not much data. My friend Bill who works in telecommunications(mostly satellites) told me about using a "pringels" can as a highly directional send-receive antenna.
It worked just great. I could focus on the area of interest. I had the computer chew on what I fed it and a pattern emerged. With Bill's help we were able to recognize "certain" conditions. The easiest and most frequent was "arousal". There was just to point the can at a certain area of the body..and there is was. (No, the best data didn't come from there).
The draw back was, the person could not be measured out side on a warm day. It worked best if the person had been inside for a time to "cool off". And even then the data was not as consistent as I wanted. To do this, we would need to "wire them" but then the data would not be spontaneous and could be faked.
I have sort of given this up for now, other things to do.
But look out, blood hounds, and the new glucose meters can see right through the skin because of the constant "shedding" of our parts. One day, a stranger will come up to you and say: "are you as ******* as this says.