14 weeks individual project
Role: Life Cycle Analysis (LCA),
System design, Product design
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POR is a radiation shield made from specialized plastic that is created through the repurposing of human waste.
As we begin to explore the possibility of landing humans on the Moon for longer missions (such as a 6-month Lunar Outpost Mission), the way we manage human waste still only supports a short visit in deep space.
POR is a construction material for lunar habitats that addresses two of the largest roadblocks to human exploration of space: radiation and waste management. 
Design Challenge
Design a lunar-based system of product/service for the year 2030. 

Conducting sustainability strategies, the overarching objectives is that the concept will create an ‘Earth/Moon Partnership’ to enhance and extend life on Earth. I chose to focus on human waste management for the early phase of long-term lunar missions.

 Research Context
Space Missions:
The Challenge of Human Waste
Currently, we depend on Earth to resupply materials and to incinerate human waste; however, as we inhabit the Moon and other locations in space, this will neither be possible nor sustainable.
Research
Research Process
Driven by Life Cycle Assessment (LCA), I broke down the astronaut's journey of using the space toilet. I also assessed the environmental impact of the current human waste management on the International Space Station (ISS) in order to pinpoint key pain points.
Observing crew member's journey using space toilet on the ISS
Analyzing Waste Management System (WMS)
Key Problem
This Linear System is Throwing Potential Resource Away With a Heavy Use of Energy and Materials.
Opportunities

_A Technology to Process Human Waste for In-Situ Resource Utilization (ISRU)

One potential waste-processing advancement that I incorporated is the Torrefaction Processing Unit (TPU). This new method allows solid human waste to convert into a stable char product, which has multiple potential uses, such as generating plastic. (Read more about this LRR technology at NASA)

Torrefaction (mild pyrolysis) processing has shown a promising result to sterilize feces and produce stable, solid product. This residue has the potential to repurpose into plastic.

Ref:NASA

Plastic tile made of recycled waste using Heat Melt Compactor (HMC). Ref: NASA

_Human Survival for Lunar Outpost Mission: Mitigate Radiation

Seeing the potential to shield against radiation from this new human waste converted plastic, this project proposes a way to turn a never-ending source of waste into a sustainable source of material for use in shielding radiation and for lunar habitat construction.

Exploring possible applications:
A roadmap to develop ideas
Design
A Water Wall Structure Inspired by Plant Leaves
Water and plastic materials mitigate radiation effectively. Inspired by the vein structures of plant leaves, the POR design uses this new plastic from human waste to form a vascular system for the habitat.
The POR Habitat Structure
The habitat specs are defined by the requirements for lunar outpost crew missions, using the studies on radiation protection and structural design for lunar habitat.
Habitat spec:
_Four crew members, rotate every six months
_Habitat volume: > 480 m3
_Water wall thickness > 0.25 m
Design Consideration:

Modular system.

Radiation:
Provide radiation protection to mitigate the dose <50 rem/yr.

Material:

_Repurposed plastic, assume it could become printable material.

_Water, which will have dual usage in the future.

Structure:

_Rigid over inflatable for long-term missions

_Spherical/ Cylindrical form to endure even radiation dose and avoid pressure tension.

The POR System
This new closed-loop system converts human waste into construction material for the lunar habitat.
The POR Unit
Inspired by leaves, the venation structure allows water to distribute evenly and provide mechanical resilience.
The cross-section of a POR unit
Prototyping
Scale models of the POR habitat and the POR unit
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All works © 2019 by Shu Ou