Solution Development

1. Design each task in a problem-solving effort so that it is most fruitful and provides the most information or guidance
   a) Autonomous: able to function without human intervention and processes flow from one to the other (HIGH)
   b) Deconstruction of source material: ability to take clean and dry PET source material (bottle or container of any size) and break it down into uniform pellets to be formed into filament (HIGH)
   c) Create high-quality filament on a spool: turn PET pellets into a smooth, uniform filament with minimal imperfections and evenly distribute produced filament onto a spool (HIGH)
   d) Safety: include safety features for a variety of end users including hobbyists and students (MODERATE)
   e) Remote monitoring: ability to monitor progress and errors of the system from a remote location (MODERATE)
   f) Process time: be time efficient and minimize down time from errors (LOW) 

2. Use various attributes of the final solution state to guide earlier decisions made along the solution path

a) Mobile application for remote monitoring of progress and errors
b) Manual press to push source material through the grinder
c) Heated extruder tip to form filament from uniform pellets
d) Wheels to smooth filament and ensure minimal discrepancies
e) Cooling fans to cool filament for spooling
f) Heated/dry box for minimal moisture while spooling

3. Define design goals and design specifications

a) The fabricator shall be able to autonomously deconstruct PET source material into pellets for filament.
b) The fabricator shall produce high-quality 3D printer filament from PET source material with high precision for minimal printer clogs.
c) The fabricator shall spool recycled filament for use in most 3D printers that accept PET.
d) The fabricator shall be supported by common power sources and be stand-alone from the 3D printer itself.
e) The fabricator shall be affordable for hobbyist 3D printers.
f)  Fabricator should accept various forms of PET source material (bottles, failed 3D printing projects, etc.).
g) Fabricator should break down plastic into workable consistency.
h) Fabricator should apply heat to deconstructed plastic to create a molten and workable form.
i)  Fabricator should force molten plastic through an extrusion tip to create continuous filament with a constant diameter.
j)  Fabricator should allow for the extruded filament to cool before spooling, with or without assistance.
k) Fabricator should automatically wind cooled filament onto a spool.
l)  Fabricator’s parts should be easy to clean and replace if needed.
m) Fabricator should contribute to reducing plastic waste. 

4. Eliminate paths that do not satisfy the desired design goals and/or specifications

After a concept generation exercise, three designs are compared with the state of the art. Following a scoring matrix, two more designs are created, one grinding system and one shredding system. These new designs were added to a weighing matrix with the current solutions. From this comparison, the grinding system was determined to be the most effective at achieving requirements and chosen for continuing design.

First Round of Concept Development:

Second Round of Concept Development: