P14415: Subsystem Design Review

1. P14415: Subsystem Design Review Patrick Morabito John Wilson Michael Coffey Nathan Conklin Samuel Svintozelsky

2. Agenda • Background and Recap Information • Engineering Requirement Flowdown • Subsystems • Proof of Concept • Prototyping • Economic Analysis • Test Procedure & Risks • Moving Forward

3. Background Information Inadequate sanitation is a major cause of preventable illnesses in children around the world. According to UNICEF, diarrhea alone causes over 1.6 million deaths in children under 5. These illnesses can easily be prevented by improving sanitation. However, cost is a major barrier limiting the adoption of sanitation in Haiti. Peter Morgan’s Arborloo is a simple latrine built over a small pit, which when filled is then moved to a new pit location. The old, filled pit then has vegetation planted on top of it, such as a fruit tree.

4. New Learnings • Meeting with Johnny • Low-cost reaffirmed as critical constraint • Building capabilities explored • Mock up build • Hole size requirement revisited • Platform size improvementsxxx

5. Engineering Requirements - Updates • S4-Maximum squat hole diameter • S8-Complexity of tools needed

6. Critical Requirements Recap • Cost • Continuously surfaces as primary requirement • Weight • Crucial to remote users • Load Bearing Ability • Main functional requirement (From Engineering Requirements) https://edge.rit.edu/edge/P14415/public/Project%20Planning%20Phase/Engineering_Requirements_14415.xls

7. Highlighted Functions • Guides Raw Sewage • Supports Weight • Separates User from the Pit • Establishes Barrier Between User and Waste

8. Subsystems • Manufacturing Process • Material Selection • Shape & Form

9. Manufacturing Processes

10. Materials Considered Cost Matrix Acquired Quotes for these materials are a little too costly.

11. Design #1 • Explored Rib Design Models • Built Full Scale Mockup • Built Vacuum Formed Scale Model • Two Directions

12. Design #1 Rib Design Set up Model Tensile Strength: 9.5 * 10 ^7 N/m^2 Fixed at 4 corners of base Load: 2000N Load *Refer to reports for mesh information 2000N Load Fixed at 4 corners

13. Design #1 Exploration

14. Design #1: Highlighted Beta Designs

15. Design 1 Rib Design Summary

16. Design #1 - Half Scale Model Purpose: • Test ABS Plastic • Test vacuum forming capabilities

17. Design #1 - Half Scale Model Cont.

18. Design #1 - Half Scale Model Cont. Lessons Learned Poor edge draft/vacuum Strong ribs & durable top surface Weak/Thin Corners

19. Design #2 • Full Scale Mockup • Material Selections • Cost Analysis

20. Design #2 Cost Analysis • 1 x 6” Design • 11/16” thick • 14’ Plastic board • 10’ 2x2 ribbing • $43.7 total • 10-¼ x ¼” • ¼” thick • 1.5 12’ board • 10’ 2x2 ribbing • $35.66 total

21. Cost Analysis - Design #1 & #2 Full Scale Models

22. Designs #3 & #4 • Not Feasible Designs • Cardboard Models • Difficult to sit and stand • Scale required to cover hole required separate supporting base • Better as Seats • Can easily be integrated with a bucket

23. Updated Risks Assessment (Technical)

24. Updated Risks Assessment (Project)

25. Updated Risks Assessment (Team)

26. Test Plan - Revisited

27. Updated Project Plan

28. Key Decisions from Subsystem Phase • Design 1: Two Directions • Plastic Ribbing & Supports • Recycled/Repurposed Material • Design 2: “Local Industry” • Designs 3 & 4: No Longer Full Designs • Possible Seat Integration • Possible Manufacturing Processes • Vacuum Forming • Rotational Molding • “Kit” • Recycled

29. Moving Forward - Next Phase • Design 1: Repurposed Materials Method • Design 2: Support Structure • Lid Designs • Seats (Upgradable) • Cleanability

30. Questions?