This is a syndicated post. Read the original at Stepleton 31/32, 2012-07-06.
In between waiting for good weather and tows, I thought I’d try to invent something. (Not a decapitated rubber duck.) The GoPro HERO series cameras are much beloved by pilots everywhere. After purchase, most new owners work out ways of tacking the things to the outsides of their planes so they can shoot their own version of essentially the same movie. Since the camera ships with a suction cup mount like this one: many attachment methods seem to involve affixing the suction cup to the wing, then taping over the cup part for extra security. Although not suitable for the wings, I thought I’d investigate a different exterior mounting method, one that would work well with surfaces with sharper curves than the wings (e.g. the fuselage) and that wouldn’t require taping or other adhesives. There is a variety of stress ball that keeps its shape when you knead it, essentially a latex balloon filled with sand or some other kind of grainy substance. What if you could make a magnetic camera mount with a magnetic base that was kneadable like those stress balls? You could keep a snug fit around the curved surfaces of a glider fuselage. There are, of course, very few iron or steel gliders out there, but I wondered further if I could make two magnetic stress balls: one as the camera mount and the other as a thing for the magnets in the mount to “grab” through the fiberglass skin of my own plane, essentially making the fuselage skin the “meat” in a sandwich with stress ball buns. So, this is what I set out to attempt. I cleaned out at least two local craft stores of their supply of neodymium button magnets, bought party balloons and assorted hardware, and scrounged some additional supplies from the kitchen. I wound up gluing the button magnets to flexible diaphragms made of yogurt container lids, burying those in plastic bags full of cheap store-brand decaffeinated coffee, then wrapping the bags in latex balloons. I was inspired to use coffee by recent successes of coffee/balloon technology in the robotics world. The result: It is a partial success. The magnetic mount is pliable (limited by the flexibility of the diaphragm). The latex material has high friction and resists sliding along smooth surfaces. The mount smells faintly of coffee, which I like, and still works as a stress ball. Unfortunately, the magnets would not be strong enough to clamp the camera to the exterior of an airplane—the slipstream would rip camera and mount right off. I think the mount would work on a car, where the magnets are right next to the steel—for what it’s worth, I drove around for a bit today with the bare mount attached to my hood. On the glider, though, the separation between the stress ball “buns” and the higher wind speeds mean it’s a no go. Still, this is only the Mark 1 prototype. I believe that the idea could be made to work with time and effort. Hopefully nice weather and tows will be frequent enough that I never get a chance to try.