the Hoverboard
the hoverboard
The goal of our honors project was to learn more about parts of STEM that particularly interested us. We are both interested in engineering as a career and love working on hands-on projects that excite us. So we decided to go through with an idea we've had since we were kids, make make an actual working hoverboard (no, not those segway things). So we decided to revisit an old design we made in middle school and improve on it.
construction
The concept was simple, build two hovercraft units and attach them to opposite ends of a skateboard deck. Each hovercraft would be a circular, individual modules made out of two pieces of wood and a single piece of styrofoam "sandwiched" together with the skirt (the bag that fills with air) attached between the styrofoam and the top piece of wood. The skirt would be made from heavy duty painter's plastic (used to keep paint off of the floor when painting walls). The power behind it all would be 2 gasoline powered leaf blowers to fill the skirts with air and lift the rider up.
We began by cutting the pieces for the hoverboard. We drew four circles, 2 1/2 feet in diameter, with a pencil and string and traced the rest with the first cut. The pieces of wood were cut with a jigsaw while the styrofoam was cut with a handsaw. We then stacked our pieces together and marked 8 sections. Each of those sections contained a hole drilled and a bolt which were the main foundation of each hovercraft and tightly held all the layers together. We then marked where each piece needed to be to properly line up, drilled the holes, and screwed in the bolts. We started with just the bottom piece of wood and styrofoam to staple the skirt to. Once it was fully attached and thoroughly duct taped, we placed the top layer on to fully secure it and keep any air from escaping through the top. when then took a smaller, circular piece of wood (about 8 inches in diameter) and screwed it into the center of the skirt to create the pocket of air underneath the hovercraft when the skirt inflates. We then cut holes into the skirt to allow the pocket to fill with air and which would escape outward underneath the skirt. The last step for each hovercraft was to drill/cut a 2 1/2 inch hole as the air intake from the leaf blowers. The final step was to bolt the skateboard deck onto the hovercraft on each end. Once it was fully built, it was time to test it! We initially had the leaf blowers sitting on the hovercrafts on their own, but quickly realized they need to be secured, otherwise they would vibrate to much and their nozzles would fall out of the intake or they would completely fall off the hovercraft. Since we were short on time, we hastily used the rest of our duct tape to secure them. Luckily, that worked well enough and we ended up with a very solid and wildly fun hoverboard that earned us an applause after our demonstration during our exhibition.
Exhibition
We had to have our demonstration outside because of how loud the leaf blowers are. Once they were secure, we started it up. Each of us tried riding it before opening it up to anyone brave enough to try for themselves. After all the fun, we turned it off and thanked everyone for coming.
The science
The physics behind hovercrafts are really quite simple. It all has to do with air pressure and airflow. When the skirt fills up with air, it fills up like a balloon. However, the air is able to escape through the holes in the bottom. But when the area beneath the hovercraft has a high enough air pressure, the air is push out underneath the skirt. This makes the hovercraft essentially float on this outward airflow which allows it to glide across surfaces. Some professional hovercrafts can even glide across land to the surface of water instantly!