Nipples. Little pleasure bundles of nerve endings, often neglected on this human's body.
Until relatively recently, I didn't experience any feeling from physical contact with my nips. However, for some reason in the past year or so, like unlocking an ability or power-up in a video game, this changed entirely.
Now that the tissue of this part of my body has become activated, the nips are sympathetic to many levels of stimulation on a spectrum ranging from pain to pleasure.
It sounds silly perhaps, but it's amazing what can go unnoticed about your own body if you don't think to explore it. This peripheral is perhaps commenting on this very sensory discovery.
How big can your nipples get? -Stop laugh. I'm serious. Do you know?
What circumstances cause them to get stiff? Is it seemingly random? Is there a relation to sensual stimulation? When it happens, do you find it pleasurable?
All of these things I had never considered until recently. And like a snowball rolling down a hill, the more I concentrated on my own awareness of these feelings, the more intensely I felt them.
If I were to detect some physical change from this part of my body that gives me visual feedback of my body's status, it would have to be size. For that- I chose to investigate how I could track fluctuations of growth from my nips.
For the first iteration of the propeller pasties, I played with a couple of IR distance sensors. They send out an infrared light, and depending on how long it takes for that light to bounce off a surface and come back, they can tell how close or far something is from them. If held directly above my nipple, they can sense even very slight changes in my nipple's girth.
This apparatus leverages the IR distance sensor to spin a propeller at a rate relative to the nipple's size (distance from the sensor).
As the propeller spins, the mechanism that provides for the spinning motion is also equipped with paddles which massage the areola of the nipple.