MECHANICAL DESIGN INTERNSHIP · UVA · SUMMER 2026
From static lab to dynamic system.
Compound gear-train teaching apparatus


I developed a tabletop compound gear-train apparatus to extend a static teaching lab into a dynamic experiment. The system uses a falling mass, three shafts, four gears, and a flywheel to connect gear ratios with angular acceleration, torque, and power.
Individual project — full ownership
This was an individual project: I independently completed the research, CAD design, fabrication, prototyping, assembly, testing, MATLAB analysis, and technical documentation. I also authored the student lab manual for planned use by more than 100 students.
Three 100 g trials produced a mean measured ratio of about 3.545 versus 3.556 theoretical (approximately 0.3% difference). A later test series yielded an estimated 84.9% efficiency using the revised inertia-based method.
Explore the design process +
Choose a teachable mechanism
After evaluating a planetary gearbox, I moved to a compound train that was easier to assemble, reconfigure, and explain in a student-led lab.
Iterate the physical design
I refined keyed interfaces, bearing fits, frame stiffness, and shaft spacing. A clearance conflict reinforced the value of checking the full assembly before printing.
Test the model, not just the hardware
I used MATLAB to explore inertia and hanging-mass choices, then PASCO rotary sensors to compare input and output motion. I replaced a circular torque calculation with an isolated flywheel test to estimate output inertia.
What the evidence supports
These are bench-test results, not a full uncertainty study. Flywheel inertia assumptions and measured-versus-predicted acceleration remained areas for refinement.





