Preliminary Detailed Design
Team Vision for Preliminary Detailed Design PhaseGoals for this phase:
- Finalize auger design
- Completely model all subsystems in CAD
- Figure out agitation method
- Design gear system
Prototyping, Engineering Analysis, Simulation
Mass and volume calculations for first auger prototype iteration
- Helped us alter the auger design to reduce volume
- Prevent clogging and overwhelming the grindstones with mass
We've created a MATLAB code to determine shaking velocity of the agitating design.
Drawings, Schematics, Flow Charts, Simulations
We determined our original design would be too large and add extra weight. We adjusted the size down from accommodating 4 kg to 1.8 kg of material, which meets the lower end of our requirements. The shaft support bar was edited to fit the dimensions of the smaller hopper design.
We also altered the preliminary agitator design to simplify it and improve its ability to prevent clogging.
The top portion of the hopper shouldn't need agitation, so we focused on agitating the portion directly above the opening to the auger.
Based on these calculations, we determined we needed to reduce the volume of breadfruit being fed into the grind stones to prevent overwhelming them.
The key changes include an increased inner diameter, increased number of threads, and a sharp edge to encourage shearing of large breadfruit chunks.
Gearbox and Grinding System
We purchased a 2:1 gearbox and modeled it in Solidworks below. Purchasing an existing gear system reduced the time, effort and money required to create the individual parts. It also allows the gears to be enclosed, thereby protecting the flour from coming in contact with them.
We then reworked how this new component would fit into the existing design and determined how it will interface with adjacent parts and drive mechanism.
Collection System Concept
The resultant flour will fall directly into a bucket placed below the stones. For simplicity, we will either have someone agitate the screens on top of the bucket or require sifting by hand.
If we believe we have time and budget available, we've developed a method to agitate the sifting screens and collecting bucket:
Bill of Material (BOM)
We've updated our risks.
Design Review Materials
Plans for next phase
High level goals:
- Order parts and materials
- Determine how/where parts will be fabricated
- Complete assembly and make adjustments to design
We've updated our Gantt chart with smaller tasks to make it more useful.