Mizzou Racing uses 3D Printing to Build Formula Racecar

An exciting time in the year is coming around, Mizzou Racing’s manufacturing season. Mizzou Racing is a Formula SAE team which means, every year, we build a quarter-scale formula-style open-wheel racecar, and every year we represent the University of Missouri-Columbia at competition against over 100 teams from around the world.

The team rests on the shoulders of several passionate college students crazy enough to build a highly competitive car from design all the way to manufacture and testing. Mizzou Racing is primarily comprised of Engineers, but the team draws members from a wide variety of majors and disciplines who are equally excited to be a part of something so unique. This multifaceted approach allows the team to attack problems with unique and often unconventional strategies.

Problem-solving makes up a major component of our year. As wild as it may seem, a racecar entirely designed and built by college students encounters the occasional hurdle. Oftentimes, challenges first present themselves in the design phase. We must adhere to a large set of rules to allow for safe and fair competition. This raises the task of finding effective solutions that are also legal. Every design on the car makes its first appearance as a SolidWorks file. In the past, most parts would go immediately from SolidWorks to production with the hope for the best results, but this method becomes cost prohibitive when final production parts are typically made from milled steel and aluminum. 3D-Printing allows for a prototype manufacturing stage where fitments and geometries can be tested and fully understood before implementation.

Rapid prototyping is both a fun and highly effective exercise for our car. Although, not quite as fun as creating final production parts. Most of our car is designed to be manufactured using a variety of machines that Mizzou Racing has been able to use thanks to the generosity of the University of Missouri and the College of Engineering. For example, our entire chassis is made of chromoly steel tubes that are welded together by our powertrain lead and president, Chris Drake, who is a senior mechanical engineering student. Many of our components are made through turning on a lathe, milling, both CNC and manual, welding, and water jetting as well as 3D printing.

3D printing finds a unique place on our team in terms of final production parts. This year, 3D prints are planned for a variety of different projects. Our intention this year is to have a steering wheel made of forged carbon fiber created inside a 3D printed mold. This project provides a unique opportunity for the combination of both 3D printing and carbon fiber manufacturing to create a part lighter and more rigid than our previous designs. Printed parts are also critical for a key aerodynamic element of our car. Our rear wing features a pneumatic drag reduction system or DRS which allows for our rear wing to temporarily reduce its downforce and drag to allow for faster speeds on straightaways. The mounting points for our DRS need to be very rigid and capable of holding up with each actuation of the DRS. The weight and difficulty of using aluminum or steel would have overcome the use of DRS for our team, but 3D printing allows for these otherwise hard-to-produce geometries to be consistently and quickly made.

Our most recent challenge came in the form of our intake restrictor. FSAE teams are required to run a 20mm restrictor on the air intake in order to limit horsepower. The rule specifies very little beyond the fact that the diameter of the restrictor must be 20mm or less at one point. This leads to a wide envelope of design options using fluid dynamics to create optimum airflow through that tight path. This year, one of our team members, Aaron Jewett, a sophomore mechanical engineering student, decided to make an attempt at further optimizing our design. This means he has ran through many iterations of fluid simulations using both SolidWorks and Ansys while also reading several research papers on fluid flow. These simulations are critical, but 3D printing and a student-made flow bench allow us to perform real-world tests on each design. We can produce several restrictor designs and get comparative data before placing any of them on the car.

The final part is 3D printed which means this testing removes the risk of any manufacturing flaws inhibiting an otherwise great design. This restrictor takes a large amount of vibrational force as well as heat which requires a high-quality print made from polycarbonate. This process of producing several copies of parts with slight changes would be impossibly expensive given any other method. 3D printing allows the team to have a development process much more in the spirit of the real-world automotive industry.

Mizzou racing has provided several fantastic opportunities to apply knowledge in incredibly broad ways. This season looks to be even more exciting than the last, thanks to many outside supporters especially MatterHackers who have allowed us to expand on our 3D printing abilities. I’m thrilled to see what the team has in store as the year goes by and we look forward to bringing others on this journey with us.