Citgo-Sign Inspired Yo-Yo's

Objective: As a student in 2.008 (Design and Manufacturing II), I worked in a team of 4 other undergraduate students to design and manufacture 50 plastic yo-yos over the course of the semester.

Solution: Taking inspiration from the CITGO Sign in Boston, my team designed the yo-yos pictured below.

The yo-yo was composed of 6 main components, the injection molded yo-yo body, red transparent pyramid, PCB, blue thermoformed letters, white cover and outer press-fit rim. The internal PCB housed a button, battery and LED and served to illuminate the transparent pyramid from behind. The transparent pyramid also served as a button, switching the LED on and off as desired.

While working on this team, I was tasked with the design of yo-yo body which housed all the electronics and other components. Creating the body posed multiple design challenges, particularly sizing its depth appropriately while accounting for button travel height, and injection molding defects. Additionally, ensuring that rim would press-fit with the body while accounting for injection molding defects like shrinkage required the use of multiple runs to assess inconsistencies in our manufacturing process.

I designed the aluminum molds for these parts in Autodesk Fusion and manufactured the tooling on the HAAS CNC. I also helped thermoform the letters and punched out the desired features using a die. The majority of the manufacturing took place at MIT’s LMP (Laboratory for Manufacturing and Productivity).

Applied Skills: Design and Manufacturing, Computer Aided Design, Fabrication and Machining, Autodesk Fusion