Inspired by the 'stillsuits' from the Dune series, researchers at Cornell University have developed a prototype urine collection and filtration system for spacesuits. This technology aims to recycle urine into drinkable water, and their findings are published in *Frontiers in Space Technologies*.

"The design includes a vacuum-based external catheter leading to a combined forward-reverse osmosis unit, providing a continuous supply of potable water with multiple safety mechanisms to ensure astronaut wellbeing," said Sofia Etlin, a research staff member at Weill Cornell Medicine and Cornell University, and the study's first author.

Designed for Upcoming Moon and Mars Missions
NASA's Artemis II and III missions, planned for 2025 and 2026, will see crews orbit the Moon and land on its south pole. These will pave the way for crewed missions to Mars in the early 2030s. Current spacesuit waste management systems, like the maximum absorbency garment (MAG), have been used since the late 1970s and function like multi-layered adult diapers made of superabsorbent polymer. Astronauts have often reported discomfort, leaks, and health issues such as urinary tract infections and gastrointestinal distress from these systems.

"The MAG has reportedly leaked and caused health issues such as urinary tract infections and gastrointestinal distress. Additionally, astronauts currently have only one liter of water available in their in-suit drink bags. This is insufficient for the planned, longer-lasting lunar spacewalks, which can last ten hours, and even up to 24 hours in an emergency," said Etlin.

To address these issues, Etlin and her team designed a new urine collection device. This device includes a multi-layered undergarment made of flexible fabric, connected to a collection cup made of molded silicone that fits around the genitalia. The cup's inner face is lined with polyester microfiber or a nylon-spandex blend to draw urine away from the body, where it is then sucked into a vacuum pump activated by a moisture-sensitive RFID tag linked to an absorbent hydrogel.

High-tech Backpack
Once collected, the urine undergoes an 87% efficient two-step filtration process using forward and reverse osmosis, removing water from the urine and separating it from salt. The purified water is enriched with electrolytes and pumped into the in-suit drink bag. Collecting and purifying 500ml of urine takes only five minutes.

The system includes control pumps, sensors, and a liquid-crystal display screen, all powered by a 20.5V battery with a capacity of 40 amp-hours. Its total size is 38 by 23 by 23 cm and weighs approximately eight kilograms, making it compact and light enough to be carried on the back of a spacesuit.

Now that the prototype is available, it can be tested under simulated conditions before being used in real spacewalks.

"Our system can be tested in simulated microgravity conditions, as microgravity is the primary space factor we must account for. These tests will ensure the system's functionality and safety before it is deployed in actual space missions," concluded Dr. Christopher E. Mason, a professor at the same institute as Etlin and the study's lead author.

Research Report:Enhanced astronaut hygiene and mission efficiency: a novel approach to in-suit waste management and water recovery in spacewalks

Related Links
Cornell University
Space Tourism, Space Transport and Space Exploration News