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ESDMD #0402: Sensorimotor Countermeasures to Support Extended Habitation in Space

Countermeasures and assessment tools for the balance and orientation problems crews have when they move between gravity levels (bin 5, rating 39 of 57). The spreadsheet is blunt about the state of the art: "There are no effective sensorimotor countermeasures". Many ISS crews cannot leave the vehicle after landing without help. Targets are 365 days in space for the Moon and 2–3 years for Mars (Tech gaps spreadsheet, ESDMD #0402).

Quotations below are from row ESDMD #0402 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. 219).

Description

"Exercise on its own will not prevent issues with gravity adaptation due to impacts on the neurovestibular system, and crew readaptation to the gravity environment is highly variable. Many crew returning from ISS with state-of-the-art countermeasures are unable to egress the vehicle after reintroduction of gravity without ground assistance. For long-duration missions, effective exploration-compatible sensorimotor countermeasures and assessment tools are needed for crew to accurately maintain and monitor physical health and performance during exploration missions."

Impacts and benefits: "Without gap closure, there is an increased risk of injury from insufficient sensorimotor adaptation."

Current state of the art

"There are no effective sensorimotor countermeasures. Exercise is an inadequate sensorimotor countermeasure. (Current ISS return is example of ineffectiveness)."

Performance target

  • Moon/Mars: "Hardware and software that are sufficient to meet crew health and performance standards for sensorimotor health to safe completion of assessment within (TBD) of preflight baseline."
  • Moon: "In addition, support mission durations up to 365 days in space."
  • Mars: "In addition, support mission durations on the order of 2-3 years."

Child gaps

  • 0402-01: Sensorimotor and disorientation countermeasures and mitigation
  • 0402-02: Sensorimotor adaptation assessment tools

Traceability

  • Use cases and functions: UC-X-103 L -- FN-X-103 L; UC-X-104 L -- FN-X-104 L; UC-X-101 M -- FN-X-101 M; UC-X-102 M -- FN-X-102 M. The four crew countermeasure gaps (#0401–#0404) list exactly these four pairs.
  • Against the Mars decomposition: the Mars spreadsheet doesn't make either Mars pair. It puts FN-X-101 M under UC-H-102 M, UC-H-104 M, UC-X-105 M and UC-X-107 M, and FN-X-102 M under UC-H-103 M, UC-H-105 M, UC-X-106 M and UC-X-108 M. UC-X-101 M and UC-X-102 M (medical care and emergency response) have emergency functions instead (FN-H-123 M to FN-H-126 M, FN-X-109 M to FN-X-112 M, FN-L-301 M, FN-L-302 M). The pairs are kept as the gap prints them (Mars use cases; open question 60).
  • Definition tasks: Mars: MD-09 Maximum Mars Crew Surface Stay Duration; Maximum Total Crew Mission Duration
  • Cross-reference: FN-X-103 L, "Provide crew countermeasure system(s) to support the crew for moderate durations (month+) on the lunar surface", is also one of the Users Guide's Phase 1 functional gaps (Users Guide, p. 9; see Phase 1 functional gaps). This link joins the two sources; neither makes it. UC-X-103 L -- FN-X-103 L also appears under #0401, #0403, #0404 and #0405.

Segments and sub-architectures

Priority

Priority bin 5, overall prioritization rating 39 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 #0402 among its near-term Moon Base challenges (Technology and knowledge challenges). Its Mars-forward area "Human factors" covers related ground without citing this gap: the Moon Base will "help mission designers better plan for prolonged missions, gravity adaptations, and partial gravity EVAs" (Users Guide, p. 14; see Mars-forward).

Sources

Tech gaps spreadsheet, ESDMD #0402 · ADD Rev C, pp. 78, 199, 219 · Users Guide, pp. 9, 14