Laser-Cut Prototype
For our third assignment in HCDE 451: UX Prototyping Techniques, we explored the use of a laser cutter to create adhesive-free prototypes. The assignment required a collection of laser-cut parts that can be disassembled and laid flat for transit. Using Rhinoceros 3D modeling software, I created an improved version of my paper prototyping phone "shell". After my paper prototyping assignment (see the first blog post), I wanted to create a higher-quality version of my Galaxy S7 phone shell. Conveniently, this assignment afforded me the opportunity to do so. Using my previous styrofoam shell as a prototype, I began designing a laser-cut, adhesive-free version of my Galaxy S7. The initial sketches can be seenbelow (Fig. 1).
Fig. 1 Sketches of the laser-cut prototype.
Fig. 2 First iteration of the prototype.
Because I already created a low-fidelity prototype version of the S7 phone shell in my paper prototyping assignment, I decided I wanted to experiment with the laser cutter for my adhesive-free prototype. I'm very glad I decided to prototype with the laser cutter, because it helped my final design immensely (in ways that a rough cardboard prototype couldn't). The laser-cut prototype is laid out to the left (Fig. 2).
My initial design included a "lock" (the oval piece in Fig. 2) as well as thicker slots for adhesive-free assembly. The slots were too thick (or tall), and I had to adjust this in the final version. Additionally, the two square pieces (what I call the "keys") were too long, and jutted out from the final shell. I adjusted for the next (and final) iteration.
Fig. 3 Rhino sketch of the prototype.
Fig. 4 Final iteration of the prototype.
The prototype above (Fig. 2) was not cut precisely enough to function free of adhesives. The slots were too large, so the "keys" wiggled too much. I re-measured the width of the chip board and adjusted my dimensions to create more friction between the "key" and "lock." This also required adjusting a few other dimensions to ensure all of the slots lined up. I also realized that the ovular piece is unnecessary, so I omitted this from my final CAD design.
The photo to the right (Fig. 4) shows the final version "in action" with a fake paper prototype screen. With this new phone shell, I can bring even more context to users while usability testing by making the phone shell sleeker and more realistic.
After I created the final prototype, I decided to test its functionality with a friend. Based on feedback from a quick evaluation, here's how I can improve this phone shell in future iterations:
- adjust slot height to create even more friction (account for "hairline" laser cuts);
- provide a "home button" piece;
- add weight;
- make the entire shell bigger (prototypes don't always have to be 1:1 with the "real world")
- experiment with additional "details" via shallow laser cuts (home button outline, samsung logo, etc.) to bring even more context to the usability testing.
