The vast majority of people do not appreciate being soaked in the rain while they are trying to commute to work or somewhere else important. And for YouTuber Ivan Miranda who lives in a coastal Spanish city, it rains a lot there. But rather than having to use and carry around a bulky umbrella, he wanted to build a hat that could keep him dry in the rain whilst taking up a minimal amount of space.
Umbrellas work by using a large canopy of fabric or plastic sheeting that is stretched over a series of metal spokes that move up or down to unfurl it. So for Miranda's hat, he wanted to use a cushion of air that sits between his head and the sky to prevent rain from falling on him. Additionally, this patch of air could blow outwards to move water further away.
The first attempt at building the turbine umbrella hat began with 3D printing several different kinds of impellers, which are cylinders that have channels cut in their sides for pushing air outwards. Miranda also chose to use a standard brushless DC motor that is often incorporated into remote control planes for turning propellers.
Once this was mounted onto a helmet, he quickly discovered two main issues. The primary one was that the motor was too weak and thus allowed water to reach the wearer. Second, imbalances within the impeller would cause the whole assembly to shake and come lose.
This second revision removed the impeller entirely and replaced it with a much more powerful RC "jet" engine that could produce a lot more thrust. Air coming from the output of the turbine is channeled downwards where it is then exhausted out from all sides, forming a nice ring above the wearer that would hopefully work better.
Miranda set up a garden hose sprinkler about seven feet from the ground to check if this improved version would keep him dry. Overall, most of the water was successfully kept away, but this was not good enough. To fix the issue, Miranda closed the gap between the top and bottom rings to make the output area match the input area in order to have a higher pressure stream of air.
Going into the final test, Miranda had plenty of hope that his latest revision would succeed in acting as an umbrella replacement. As seen in his video, it worked, albeit with quite a bit of fan noise.