Rubber Band Propelled Dune Buggy

This Dune Buggy operates by building tension in a rubber band. You pull it back on the ground to build tension, and then let it go. It will propel forward as the tension is released.

The Dune Buggy has 4 different parts:

• Dune Buggy Body x 1
• Axles x 2
• Wheels x 4
• Rubber Band x 1

The supplies you will need for this project are as follows:

• 3D Printer
• 3D Printer plastic
• Autodesk Inventor
• Rubber Bands

I began my project by sketching out multiple designs for the the type of car I wanted to design. I decided on the Dune Buggy design which is the bottom sketch in this image. I believed this design would allow for optimal performance as it is a balanced design.

I started with a 5"x3"x3" box. I decided on this size because it would fit in the 3D printer that I have available. I then designed the general shape of the body of the Dune Buggy by extruding out areas of the box. Some minor changes were made to the shape of the body farther into the project, however this is the general shape of the body.

Next I needed to design the interior seats. This part of the design was the most difficult part. I needed to remove parts of the inside of the Dune Buggy while leaving enough support and material for the axles and the area for the rubber band. Through trial and error I decided on the bench seat design. This design did not intrude to far into the Dune Buggy leaving space for the axle gaps and rubber band hole. The axle gaps are slightly greater than 1/4" so the 1/4" axles will fit. The wheel wells are 1/2" In depth. The Square Hole is 1/2"x1/2"x1/2". This leaves plenty of space for the rubber band to coil.

In this step I added a piece on the front of the Dune Buggy for the Rubber band to wrap around. This holds the rubber band in place while it coils and builds tension. I rounded the top of the latch to disperse pressure and decrease the chance of the rubber band breaking.

This step involved me making the Dune Buggy more appealing. I rounded off many corners and edges to make the buggy appear less blocky. I also added a bit of text on the hood of the Dune Buggy. The "W" stands for my school's logo, and the "Demons" Stands for my school's mascot.

In this step I designed the axles for the Dune Buggy. I added key slots on them so the wheels could lock in place. The axles are 1/4" in diameter, and are 3.5" long. This allows the wheels to hang out of the Dune Buggy on both sides by 1/4". This will also give a 1/4" of space between the wheels and wheel wells.

In this step I designed the wheels for the Dune Buggy. I knew I needed large wheels to fit the Dune Buggy look. As well as to allow the Rubber Band a greater area off of the ground. The key slot allows the wheel to lock onto the axle. The wheels are 3/4" in Diameter with a 1/4" Diameter circle cut out to fit onto the axle. They are 1/2" in depth/width.

Assembling the Dune Buggy is a very simple process. The front axle slides through the axle gap and you place wheels on both ends of that axle. The back axle slides through to the hole. Here you tie this simple two step knot on the axle and then thread the axle the rest of the way through. This will prevent the rubber band from slipping along the back axle. If the rubber band would slip it would be prevented from coiling, so this is a very important step, make sure you pull the knot tight to the axle after threading the axle through to the other side. You then attach the other end of the rubber band to the front hatch. Finally you put wheels onto both sides of the back axle. Now the Dune Buggy is ready to go!