In this freshman-year build, Victor and I took a bare chassis, four AA-powered motors, and hardboard wheels and turned them into a fully functional track-running trolley. I led the CAD-and-3D-print iterations on our two-speed gearbox—measuring and compensating for printer tolerances, redesigning axle mounts for perfect alignment, and laser-cutting a lightweight frame to lower our center of gravity. I also handled parts sourcing and electronics: mounting the batteries, Arduino, MOSFET, and sensors with a mix of superglue and Velcro to save weight and assembly time. Through systematic testing—removing print supports by hand, tuning gear clearances, and adding rubber bands for traction—our trolley ran cleanly on the course, climbed inclines without slipping, and never suffered a major failure. This project was my first real lesson in rapid prototyping, precision tolerancing, and iterative problem-solving.