Thanks to their shoe box-like size, CubeSat satellites are becoming increasingly popular for many applications – after all, their construction and launch costs are way less than those of their traditional counterparts. One down side of that small size, however, is the fact that they can overheat or get too cold very quickly. With that in mind, scientists have created a new type of temperature-regulating radiator for CubeSats … and it does its job by folding, just like origami.
Created by Brigham Young University assistant professor Brian Iverson and doctoral student Rydge Mulford, the radiator itself is made up of a series of V-shaped structures that can be folded open or closed.
That folding action could in turn be accomplished by using temperature-sensitive materials such as shape-memory alloys. As the satellite heated up due to sunlight exposure or the operation of its own electronics, the radiator would automatically fold inwards – the deeper the folds, the greater the amount of heat is absorbed.
Once that heat has been absorbed, though, it still needs to be gotten rid of. That's where NASA scientist Vivek Dwivedi comes in. He's experimenting with coatings for the radiator, which would help it to emit the heat into space.
Vivek Dwivedi, in front of a sputtering reactor used to deposit vanadium-oxide onto sample substrates.
More specifically he's looking at vanadium-oxide, which emits heat when it changes from a semiconductor to a metal state, upon reaching a temperature of 154 ºF (68 ºC). Working with the University of Maryland's Prof. Raymond Adomaitis, Dwivedi is attempting to lower that transition temperature to something more practical, by coating the vanadium-oxide with thin films of silver and titanium.
"This approach has the potential to be a game changer in thermal design," he says. "Our goal is to replace traditional radiators with dynamic ones, period."