Northwestern Formula Racing
Suspension Engineer, Creative Director
September 2015 - Present
Formula SAE is a global, collegiate competition in which teams design, build, and compete with Formula 1 style race cars. I am currently a suspension team member and the creative director, but I also help with the design and manufacturing of components for other subteams.
As a suspension team member, I focus on balancing weight-savings with performance. For example, while designing the wheel centers and rockers, I lowered the target fatigue life cycles after determining that the criteria used in the previous years were excessive. I then went through iterative finite element analysis (FEA) trials to develop designs that hit the weight savings and moment of inertia reduction goals. As the creative director, I create all advertisement materials and design the aesthetic elements of the car, such as the paint job and aerodynamic endplates.
This is NFR17, the second car I worked on with the team. My main project for the year was to design and manufacture the wheel centers, which hold the wheels together and interface with the hubs, transferring the load from the ground into the corner.
Since in the past years our factor of safety (FOS) was constrained by the fatigue life, resulting in relatively high FOS to yield (around 2), I reevaluated our approach to fatigue analysis. I determined that designing for 1 million cycles of cornering at 30 mph was a more realistic estimate of the car's actual run time than 6 million cycles of cornering at 60 mph. This allowed me to hit my goals of 5% weight reduction and 15% moment of inertia reduction. After completing the design, I developed the CAM program to manufacture the wheel centers on Siemens NX (Unigraphics). While I did the majority of the work on CNC mills, I machined the blanks on a manual mill.
Another major project I worked on for NFR17 was designing the aerodynamics package mounts. Being only the second year with an aerodynamics package, there was a lot of room for improvement with the mounts, namely their rigidity and weight. In this case, it was best to design for rigidity to avoid disturbing the air flow and to comply with the competition rules dictating the maximum movement of the wings under given loads. I ultimately decided to go with aluminum sheet metal "swan necks" and carbon fiber tubes to provide lateral suppport. This also minimized the profile of the mounts from the previous year, reducing drag.
Once I completed my main projects, I helped manufacture other components. I focused on cutting the total manufacturing times by introducing new, but ultimately beneficial, machining techniques. For example, by teaching myself to use a t-slot cutter, I eliminated the need to turn the outer grooves on the center-locking nuts, reducing the process to a single, CNC setup (top left). Rather than manually milling the blanks for each clevis, I programmed the CNC mill to machine out all 6 in a single setup, leaving a single manual mill setup for the perpendicular holes, cutting down from 6 CNC setups and 6 manual mill setups (top right). Additionally, I learned how to manufacture titanium for the anti-roll bar (bottom left) and taught the new members how to program planar operations to machine the rockers (bottom right).
As the creative director, one of my main responsibilities is leading the design of the aesthetics-driven elements of the car. The rear wing endplates went through the most iterations of these components, until I developed a design that complemented the curvy body work and simultaneously added an aggressive touch. Above are 4 of over 20 designs that I created. For the paint job, I chose to go with a classic style that highlighted our school colors, with the endplates matching the football team's helmets.
This is NFR16, the first car I worked on with the team. My primary project was the design and manufacturing of the rockers, the elements that interface the shocks with the pullrods and ARB, setting the motion ratios. I moved to an aluminum design and performed a thorough analysis of the various load conditions to test in FEA, as the steel sheet metal design from the year before had failed in an unexpected bending load scenario. This also allowed me to cut the weight of the rockers in half. The final design required a single CNC setup for all 4 rockers and 2 manual mill setups of the individual components.