REACT: A Portable Hyperbaric Shelter for Mars EVAs (ACHIEVED 2025)
Team RedHorizon’s emergency EVA shelter to mitigate decompression sickness (DCS) on Mars. Presenting at SGAC 2025 in Sydney.
Introduction
Decompression sickness (DCS) can threaten astronaut safety during EVAs on Mars if pressure drops rapidly (suit puncture, protocol error, forced repressurization). REACT — the Rapid Emergency Action and Contingency Tool — is a lightweight, deployable, soft‑shelled hyperbaric shelter that quickly repressurizes and stabilizes an astronaut in the field while a rescue is mobilized.
Context and Objectives
- Gap: Pre‑breathing protocols and suit gaskets reduce risk but do not treat active DCS in the field.
- Objective: Provide a portable, rapidly deployable, autonomous shelter that restores survivable pressure, maintains life support, and communicates for rescue.
- Mars constraints: Thin atmosphere (manual pumps ineffective), dust, temperature swings, long distances from habitat/rover, and the need for simple operation with gloved hands.
Design Definition
- Form factor: Backpack‑carried, tunnel‑style chamber with horizontal entry flaps for drag‑in ingress (conscious or assisted patient).
- Deployment: Spring‑assisted single‑person deployment with fold‑out gates that seal as pressure rises.
- Pressurization: Composite Overwrapped Pressure Vessel (COPV) and a PID‑controlled valve for smooth, stable pressure control to suit‑like conditions.
- Life support: Internal circulation fan and CO₂ scrubber (solid amine/LiOH). Gas‑impermeable multilayer liner limits diffusion.
- Comms: Standalone UHF beacon with reed‑switch auto‑activation on deployment; relay‑friendly architecture for terrain‑blocked scenarios.
- Monitoring/Transport: External viewing window; handles/straps to carry the chamber to a rover for evacuation.
Materials and Structure
- Shell: Kevlar aramid fiber composite (proven in portable hyperbaric chambers) with multilayer Mylar/polyethylene liner.
- Rationale: Single‑layer envelope reduces mass and gas volume versus inflatable skeletons; optimized for quick deployment and sealing.
Feasibility Highlights
- Technical: PID‑based pressure regulation; autonomous activation; modular comms; backpack mass target under ~20 kg (Mars gravity effective weight lower).
- Economic: Niche, mission‑critical hardware; development cost justified by risk reduction and mission assurance.
- Environmental: Durable materials for reuse; low operating duty cycle; designed for temporary deployment with minimal surface impact.
Operations Protocol (Excerpt)
1. Detect emergency symptoms or suit failure; deploy REACT (~60 s).
2. Drag or assist the astronaut into the chamber; gates seal as pressure rises.
3. PID controller maintains target pressure; circulation and CO₂ scrubbing active.
4. UHF beacon activates and propagates distress via relay/repeater/habitat.
5. Rescue rover retrieves chamber; patient triaged at habitat hyperbaric facilities.
Risks and Mitigations
- Leakage or poor retention → seam testing, sensors, multi‑layer structure.
- Deployment failure → redundant spring/gas assist; manual override.
- Mass/volume constraints → strict audits; modularity; lightweight composites.
- Terrain‑blocked comms → deployable relay nodes and rover relays.
Team and Credits
Team RedHorizon — Haaniya Ahmed, Alisa Norenberg, Garret Langlois, Safana Al‑Emara, Dylan Vaughn Villanueva — competing at SGAC (Sydney, Sept 2025). Prepared June 9, 2025.
Conclusion
REACT addresses the missing “field treatment” layer for DCS on Mars EVAs: rapid deployment, autonomous pressurization, and reliable comms for fast rescue. It is a pragmatic, reusable safety system designed to protect crews and preserve mission continuity during surface exploration.