Skip to content

ESDMD #0406: Spacesuit Physiology for Deep Space Missions

Tools to predict, monitor and prevent injury to suited crew, validated pre-breathe protocols, and crew health data available during EVAs without real-time ground support (bin 5, rating 43 of 57). EVAs become more frequent on long missions, with less recovery time. Suit fit "is well understood in microgravity but not lunar gravity", and pre-breathe for lower-pressure, higher-oxygen habitats "is only partially validated" (Tech gaps spreadsheet, ESDMD #0406).

Quotations below are from row ESDMD #0406 of the tech gaps spreadsheet unless marked otherwise. ADD Rev C's Appendix D prints the same table for this gap, and it matches the row field for field (ADD Rev C, p. 223).

Description

"Currently there is not a fully validated pre-breathe, injury modeling, and self-health monitoring capability. There is a reasonable risk of reduced science or activities supporting mission objectives if injury occurs. As missions increase in duration, EVA frequency significantly increases due to reduced recovery time. Providing the crew time-critical health data & contingency con-ops information for crew risk decisions is important for even short time delays or loss of communication. Capabilities advancement is required for spacesuit physiology, especially as it pertains to conducting surface EVA and ingress/egress from habitable assets."

Impacts and benefits: "Failure to close this gap will result in EVA planning, operations, training, system design, and/or decision support systems that have a risk of being inconsistent or incompatible with crewmember capabilities and constraints. This will also preclude crew health and performance assessment and decision-making during exploration EVAs with intermittent or delayed space-ground communications. High likelihood of multiple mission-impacting injuries during exploration missions involving high-frequency EVA."

Current state of the art

"Real-time Crew Health and Performance decision support during ISS EVA operations is provided by ground-based flight controllers with high bandwidth and near-zero latency space-ground communications. Suit-to-crew fit is well understood in microgravity but not lunar gravity for a walking or sitting suit configuration. Prebreathe protocol for lower pressure higher oxygen habitats is only partially validated."

Performance target

Moon/Mars: "Dependent upon future integrated risk assessment trades, improved spacesuit physiology capabilities, such as tools to predict, monitor, and mitigate EVA crewmember injuries. Solutions capable of supporting Moon and Mars mission EVA strategy with acceptable risk of adverse outcomes."

Child gaps

  • 0406-01: Earth-independent health monitoring and decision support during exploration EVAs
  • 0406-02: Suited injury prevention and mitigation
  • 0406-03: Decompression stress prediction and mitigation

Traceability

  • Use cases and functions: UC-M-101 L -- All FN; UC-M-102 L -- All FN; UC-X-102 M -- FN-H-124 M
  • Definition tasks: Mars: Maximum Total Crew Mission Duration; Surface Ingress/Egress Strategy; Surface EVA Capability Strategy

Use case UC-M-101 L also appears under #0801 (with FN-M-101 L) and #0807 (with FN-M-203 L).

Segments and sub-architectures

Priority

Priority bin 5, overall prioritization rating 43 of 57. The rating is "the gap's location in the prioritized list of gaps", so 1 is the highest priority, and bins group gaps of similar priority, bin 1 highest. Criticality, urgency, breadth and depth set the order; cost is not considered (ADD Rev C, pp. 78, 199; method on the gaps index).

Moon Base relevance

Not established by the sources so far. The Users Guide does not name #0406 among its near-term Moon Base challenges (Technology and knowledge challenges). Its Mars-forward area "Human factors" mentions planning for "partial gravity EVAs", without citing this gap (Users Guide, p. 14; see Mars-forward).

Sources

Tech gaps spreadsheet, ESDMD #0406 · ADD Rev C, pp. 78, 199, 223 · Users Guide, p. 14