The product that I made is a 3D printed car designed on Onshape that can accommodate a pair of PASCO low friction wheels, a PASCO fan, and a small metal rod. When fully assembled, the fan has to be turned on, and the car can move down a PASCO track. The fan's angled propeller blades rotate and push the air, so the air pushes back, allowing the car to move. The overall goal of this project was not only to make an arrow dynamic, efficient car that could reach the highest top speed, but also to calculate and understand all the energy transformations (by way of conservation of energy) that take place after the fan is turned and makes the car move.
Overview and Background
These are the constraints that I had to work with when designing my car.
These are the original sketches of my car.
How I Designed My Car
To start the design process, I first searched up "fan powered car" on Thingiverse. One model in particular got my attention, that being a car with a pointy, sloped nose. In my initial designs I tried to incorporate this aspect since I wanted for there to be minimal air resistance acting on the car while it was in motion. First I tried to sketch a car that had a nose in the shape of half a rectangular pyramid, the bottom of the car being the flat surface of the shape. But I saw that I could make the car sleeker by rounding it, so I made the nose half of a cone. Along with this, I made the edges of the car rounded according at the same angles as the nose. However, the car was too low to hold the fan, as it did not have enough flat space on the sides. Combating this, I made the car taller. This design was printed, yet there were two main problems: the fan could not sit properly on the car without overlapping with the wheel arches and covering the hole for the metal rod, and the wheel arches were not large enough for the wheels. In order to fix the first design flaw, I added walls on the sides of the car that came up just slightly taller than the rounded top of the car, allowing for the fan to be attached at such a height that it did not cover the wheel arches. Also, I moved the hole for the metal rod all the way to the utmost end of the car, so the fan would not interfere with its space. As for the wheel arches, I extended their size so that the wheels would fit inside them and not brush against the side of the car. When printed, the car could have the fan attached to it and the metal rod put in it, all while sitting and moving comfortably on the wheels.
Steps to Assembling My Car
Attach the PASCO low friction wheels to the car by placing them onto the grooves on the bottom of the car, and applying pressure until they snap into place.
- Put the fan on so that its sides can grip the flat parts of the sides of the car, making sure to not attach it too low where it covers the wheel arches.
This video shows me putting my car together.
This video shows my car competing with others.