Meet the Yo-Yo

Description of Yo-yo Design

Our yo-yo is based off of the story of the tortoise and the hare from Aesop’s fables. One side is a tortoise, with the shell taking up the entirety of the circular yo-yo. The other side of the yo-yo is the body of the hare. Our idea is that as the yo-yo spins, the tortoise and the hare will be chasing each other around in an endless footrace.

The shell of the tortoise and the body of the hare will both press-fit into two sides of the same body part. All three parts will be injection-molded. Meanwhile, the stand will be thermoformed. The two pieces sticking out, the head of the tortoise and the tale of the hare, will be made out of felt or another lightweight material, so that it won’t affect the rotational mechanics of the yo-yo. These will be laser-cut.

As for the division of the team, Khanh and Joshua will be working on the tortoise, Elizabeth and Mario will be working on the hare, and Thulith will be working on the stand. The entire team will be coordinating and working on the body part.

TORTOISE

 





HARE

 



STAND

      

Assembly




DFM Incorporation

                  All of our yo-yo parts have design for manufacturing considerations. The parts are all created using mass-manufacturing processes, such as injection-molding, thermoforming, and laser-cutting. This means that we just need to get the molds correct in order to create multiple parts. In addition, the two halves of the yo-yo body part that the tortoise and the hare will snap on are actually the same part, so instead of needing to create four different injection-molded parts, we’d only need to create three.

                  As for the big four (rate, quality, cost, flexibility) – we imagine that with a larger scale, it would be a fast rate and a low cost. Quality would be low to medium, and flexibility would be low since injection-mold tooling would have to change in order to change the design.

Table of Specifications

Critical Dimension
Target Numerical Value in SI Units
Expected Tolerances
How We Will Measure the Values
Diameter
0.0762 m
± 0.0001 m
Caliper
String Gap
0.0019 m
± 0.0001 m
Caliper
Total Mass
0.083 kg
± 0.01 kg
Scale
Max Rotational Speed
95 rad/s
n/a: this is an estimate
Computer program

Gantt Chart

Link to Gantt Chart

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