Vacuum-Driven Waste Compaction for Spacecraft Water Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional waste compaction systems in spacecraft, such as those used in the Space Shuttle and International Space Station, are inefficient in water conservation and heavy due to reliance on motorized actuation and air flow, leading to water loss when disposing of fecal waste.
Innovation Solution
A waste compaction apparatus utilizing the near-vacuum of outer space to compact waste materials, where a drive chamber is exposed to space vacuum, creating a pressure differential to move a compaction piston and extract waste fluid, which is then separated into liquid and gas using a gas-liquid separator, allowing for water recycling and efficient waste management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If motorized actuation systems are used for waste compaction, then compaction function is achieved, but device weight increases and system complexity increases
Solution Approach 1:
The patent replaces motorized mechanical actuation systems with a pneumatic system that uses pressure differential (vacuum) to drive the compaction piston. The drive chamber is exposed to space vacuum, creating a pressure differential that moves the piston without requiring motors, thereby eliminating heavy motorized components while maintaining compaction functionality.
Solution Approach 2:
The system uses the space vacuum environment itself as the power source for compaction. The natural vacuum of space provides the driving force through pressure differential, eliminating the need for external power sources or complex actuation mechanisms. The waste compaction apparatus essentially uses the environment in which it operates to perform its function.
2Ease of operation
If air flow is used to entrain waste, then waste collection is achieved, but water is lost from the spacecraft
Solution Approach 1:
The patent replaces the air flow entrainment system with a direct mechanical compression system. Instead of using air currents to move and collect waste, the system uses a piston driven by pressure differential to mechanically compress and expel waste. This mechanical approach allows for more controlled waste handling and enables subsequent water extraction through heating and condensation, preventing water loss.
Solution Approach 2:
The system is designed to recover water from waste through heating and condensation processes. The waste is compressed and heated, causing water to evaporate and then condense in a condenser, from which it can be collected and reused. This recovery process transforms the previous approach of simply discarding waste (and its water content) into a system that recovers valuable water resources.
3Productivity
If conventional waste collection systems are used, then waste disposal is achieved, but system weight increases due to motorized components
Solution Approach 1:
The patent eliminates motorized components by using a pneumatic actuation system driven by pressure differential. The drive piston is moved by the vacuum environment acting on the drive chamber, replacing heavy motors and electrical systems with a lightweight pneumatic mechanism that achieves the same waste compaction and disposal functionality.
Solution Approach 2:
The system utilizes the space vacuum environment as its power source, requiring no external power supply or heavy drive mechanisms. The pressure differential between the vacuum-exposed drive chamber and the waste-containing compaction chamber automatically drives the compaction process, making the system lightweight and self-powered by its operating environment.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively reduces waste volume on spacecraft, conserves water by recycling it from fecal matter, and eliminates the need for motorized components, thereby reducing weight and resource loss.
Implementation Method 1
utilizing the near-vacuum of outer space to compact waste material... exposing a drive chamber of a housing to the near-vacuum of outer space and compacting waste material within a compaction chamber of the housing
Implementation Method 2
The waste compaction apparatus may further include a heater coupled to the housing and configured to heat the waste material contained with the compaction chamber
Implementation Method 3
the compaction chamber is configured to expel a waste fluid via the fluid outlet to the gas-liquid separator... the gas-liquid separator is configured to separate the waste fluid into waste liquid and waste gas
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A waste compaction apparatus (100) may include a housing (110) and a connector arm (120). The housing (110) may define a drive chamber (112) and a compaction chamber (114) and the connector arm (120) may include a drive piston portion (122) movably positioned within the drive chamber and a compaction piston portion (124) movably positioned within the compaction chamber. The drive chamber (112) may be selectively fluidly coupleable to the near-vacuum of outer space, such that the compaction piston portion (124) of the connector arm is configured to move within the compaction chamber (114) to compact waste material contained within the compaction chamber (114) in response to movement of the drive piston portion (122) of the connector arm within the drive chamber (112).