Marble Launcher
A marble launcher inspired by the Stanford Dish telescope
Date
2022
Role
Mechanical Engineering
ME102
Problem + Constraints
- Design a mechanical desktop perpetual marble launcher
- Must use rotary motion input + spring reset
- Strict material constraints (acrylic, plywood, 3D print)
Inspiration + Research
- Pinball machine (high-velocity launch, track behavior)
- Magnetic loop launcher (airtime + return via ramp)
- Stanford Dish (funnel geometry inspiration)
Ideation + Sketching
- Generated multiple concept sketches
- Focused on exploring mechanism possibilities
- Goal: maximize idea quantity before narrowing down
Prototyping + Testing
Ball Displacement Mechanism
Tested slot shapes (circle, oval, triangle, square). Circular slot performed best.
Funnel
Tested angles (90°, 75°, 60°, 45°, 30°). Chose 60° for best alignment + manufacturability.
Bad funnel angle: balls block each other
Low fidelity prototype
Spring Integration
Tested attachment locations. Found optimal slot for linear stretch + max extension. Incorporated hard stops.
Launch Hammer
Iterated block width (.35 → .6 in). Identified consistency issue → redesigned.
Higher fidelity prototype
Iteration + Adjustments
Final Assembly + Documentation
CAD model
Takeaways
- Break problems into subcomponents
- Precision is critical
- Plan before lab work
- Ambition increased challenge but increased reward