Helicopter Project

My name is Michael and I am a senior at Wachusett Regional High School. The goal for this project was to use the materials found in the classroom and build a rubber band helicopter. When building a helicopter, you must take all of the four forces into consideration; lift, weight, thrust, and drag. Lift is the upwards force that enables a helicopter the ability to fly. Weight is obviously the downwards force (how much the helicopter weighs). Thrust is the force that allows a helicopter to move forwards, back, left, right, etc. Finally, drag is the force that resists the helicopters movement. I based this prototype off of the shape and function of a real helicopter (same shape of body, same blade shape, etc.). For this prototype, you will need various materials including 3 inch rubber bands (3), a 3d printer, 3d filament, superglue, balsa wood, pliers, and wire cutters. The filament used in this prototype was PETG due to the fact that it is super durable and has a high strength so that when it is dropped, the body does not break.

The first step is to create the body of the helicopter in a CADD program. I made my helicopter 6 inches long and 2.5 inches tall.

The next step is to 3d print the helicopter. Print the helicopter with .8mm thick walls with supports and a raft. The speed of the print and the infill does not matter. Once the body is printed, carefully remove the raft and all of the supports.

Cut a paperclip into an elongated horseshoe shape and then by using superglue, attach it to the flat section of the helicopters body. Use pliers to ensure that the paper clip stays standing correctly. Once the superglue is fully cured, use a dremmel to drill a hole into the top of the helicopter, directly above the paperclip. Then superglue a bead in the top hole and wait until it fully cures.

While the glue is curing on the body portion of the helicopter, cut a piece of balsa wood to 18 inches by 1.5 inches. After cutting it to size, drill a hole in the middle and superglue a bead in it. Wait for the glue to cure and then wet the wood and place it in a mold to bend the blade. Once the blade is dry and bent, use superglue to glue a straight paperclip into the bead of the blade and let cure.

Take two beads and place them on the paperclip that is glued to the blade. Then string the paperclip through the bead on the body of the helicopter. After the paperclip is through, use the pliers to bend the end of the paperclip into a hook shape. Once the hook is made, attach three rubber bands connecting the hooked paperclip on the top and the glued paperclip on the bottom.

It was quickly found that when the propeller spun, it came in contact with the tail of the helicopter, removing its ability to spin freely. This was a huge issue and was solved by using a dremmel to shave off parts of the tail to the point where it did not clip anymore. This slight modification allowed for the helicopter's blade to be able to spin without interruption. A second modification was that tape was used on the bottom part of the body in order to add extra strength without addin

After testing, I concluded that unfortunately, the helicopter did not fly. The lift generated by the blades was clearly not enough of a force to overcome the weight and the force of drag the helicopter also had. If I had more time, I could make the helicopter even smaller or increase the size of the blade in an attempt to make the helicopter fly.

The picture shows the final prototype built. As seen in the picture, there is a 3d printed body that plays as housing for all of the helicopters components. Then there is a clip at the bottom that rubber bands are attached around and then strung up to the propellers hook. The propellers hook extends through the top of the helicopter, through 2 beads used as spacers, and super glued into the blade. Overall, this is a pretty simple prototype and does not have many complex parts.