Mass and Cost Optimized Bedside Shelf


Overview: My roommate kept dropping his phone off his 6ft high bed, so I challenged myself to make a shelf with a phone holder with the least mass and cost possible.

Role: Individual Project

Responsibilities: Design, prototype, test,and manufacture final product

Skills: FEA, MATLAB, CAD, Tolerances, Laser Cutting, Force Analysis

The Challenge:

Completely design, test, and fabricate a bedside shelf with the least mass and lowest cost possible.

Action:



  1. Concept Sketches

    • Originally inspired by car hoods!

    • To avoid adhesives, I decided to use friction fits.

    • Focused on DFA because sliding each wall in would require a specific order of assembly.

    • Considered integrating functionality of slots with aesthetics.

  1. Low-Fidelity Prototype

    • I prototyped with cardboard and tape.

    • Realized it would be easiest to assembly if the base piece had all tabs and the sides had all slots.

    • I learned that a quick prototype really helps to see proportions of a design, which help intuit possible failure or design issues.

  1. CAD Model

    • I wanted a more dynamic design -> added wheels and made a shopping cart!

    • Used parameters to ensure walls fit together.

    • Applied joints to visualize assembly.

  1. Tolerance Testing

    • Created test cuts to find tolerance ranges for my friction fits.

    • These compensate for kerf from laser cutting.

    • Adjusted parameters on CAD to match test cuts.

  1. Laser Cutting

    • I uploaded my design as a DXF file to Adobe Illustrator and added a Trader Joes engraving.

    • Cut my piece in the laser cutter!

  1. Final Product

    • Moment of truth… the pieces FIT!

    • Finally created a 2D engineering drawing.

Results:

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