Baja SAE Racing - Design, Machine, Race:

Design:

As drivetrain lead for the majority of my undergraduate career, I was responsible for designing the entirety of the drivetrain system for a single seat off-road vehicle. This included, but was not limited to, a custom continuously variable transmission (CVT), acustom dogtooth clutch to switch between 4x4 and RWD, custom gear boxes (containing both spurred and bevel gears), as well as a custom u-joint to deliver power to the front wheels for 4x4 (see video to the right). Unlike majority of the drivetrain system, the engine was stock, and all teams were prohibited from making any engine, intake, or exhaust modifications. This made the importance of an efficient (and reliable) drivetrain system paramount - dividing the winning teams from the

losing. I largely credit the textbook "Shigley's Mechanical Engineering Design" for providing me with the required calculations, SN curves, and material properties to create lightweight designs that were reliable. Though my undergraduate degree provided me with background knowledge for understanding content found in Shigley's, my schooling wouldn't have been enough to design a car from scratch. For example I used formulas found in Shigley's to design shafts that were to last indefinitely (avoiding fatigue failure) from variable and cyclic loading. I also used Shigley's to create heat treating recipes that improved material strengths (and sometimes hardness depending on the application) of various components like gears allowing me to remove more material for weight savings. I also used Shigley's for complex design calculations (particularly bevel gears) to create custom sized gears from scratch. Of course, much of these initial designs were then studied using SOLIDWORKS' FEA program before undergoing several rigorous design reviews with my teammates of various sub-teams and engineering majors. The images below highlight some of these complex designs that I later machined.

Primary CVT design (side view) beside the completed product machined by myself on a manual mill and lathe.

Hey! That's me!

Machining:

Before I even started university, I began my machining training at the age of 13. Attending a vocational high school I was trained on manual lathes, manual vertical mills, CADing for and operation of CNC lathes, mills (5-axis), laser cutters, and wire EDM machines. When I entered university and joined the Baja team I became the primary machinist due to my experience at such a relatively young age. It's a real pleasure to not just design something and see it come to life, but be the one who actually creates it. My skills on a manual lathe (aside from the basics of turning and facing) include internal boring, threading (via cutting tool), grooving, and of course chuck and jaw removal and flipping. Likewise my skills on a manual

vertical mill include full and partial face milling as well as end milling. Much of the milling work I performed was on a rotary table to create somewhat concentric shapes (like triangles) for weight savings. It goes without saying, most of this work was precision (typically ± 0.005"), sometimes within 0.0005" for various press fittings of bearings and bushings. Please refer to the images below to browse only a handful of my machining projects.

Spur gear set, blanks machined by me, hobbing was outsourced. Gear cases designed and CNC milled by myself as well.

Racing!:

me again!

At the end of every design and manufacturing cycle in May/June we get to travel across North America to compete with other top schools and teams. Points are not only scored in the endurance race but also in maneuverability, acceleration, sled pull, design, cost and many other categories. After a pause in races due to covid, the McMaster Baja team had a huge year, finishing in the top ten of all of North America in 2022.