Item Details

abstract

The National Aeronautics and Space Administration (NASA) is preparing for the next manned space mission to the Moon with the aim of developing capabilities for the exploration of Mars. Astronauts experience large transient accelerations during the launch and landing phases of the space mission, which may cause injury. Even a minor injury in space can jeopardize the mission by pre-disposing astronauts from performing mission duties, and may also prove fatal by compromising their emergency egress capabilities. There is a need to understand astronaut responses under spaceflight-related loading. For future lunar missions, there is a possibility that astronauts may pilot a lunar lander in a standing or upright/reclined seated posture instead of a conventional recumbent posture. However, the effects of different postures on astronaut response are not known. Another concern for long-duration space missions is microgravity-induced musculoskeletal changes in astronauts, which may affect their injury risk tolerance. NASA is looking for innovative tools and technologies to predict injury risk in the astronaut throughout the space mission. Due to the high cost and complexity and lack of reflex response, conventional tests using post-mortem human subjects or anthropomorphic test devices are limited for this purpose. However, computational human body models (HBMs), due to their time and cost-effectiveness and ability to simulate the active muscle response, are emerging as an alternative for studying injury biomechanics in space applications. The objective of this dissertation was to develop computational tools and methodologies to simulate spaceflight loading conditions, and to assess the effects of loading conditions, postures, and space-induced muscle deconditioning on the astronaut kinematics and injury risk. This objective was achieved in three parts: 1) First, the standing and upright/reclined seated postures of astronauts for the lunar mission were simulated using the Global Human Body Models Consortium (GHBMC) HBMs, and differences in the body kinematics and injury risk were characterized. 2) Second, an active muscle HBM in a standing posture was developed and validated against the volunteer response in a step-down test, and the effects of active muscle on astronaut response for lunar missions piloted in a standing posture were characterized. 3) Finally, a modular simplified HBM with a deformable spine was developed and validated to study the effects of musculoskeletal changes in a computationally efficient manner, and a sensitivity analysis across 600 simulations was carried out to assess the effects of the spaceflight loading parameters and muscle deconditioning.

subject

Active muscle modeling

Artemis lunar mission

Computational human body model

GHBMC

NASA

Sensitivity study

contributor

Lalwala, Mitesh (author)

Weaver, Ashley A (committee chair)

Gayzik, F. Scott (committee member)

Willey, Jeffrey S (committee member)

Stitzel, Joel D (committee member)

Currie-Gregg, Nancy J (committee member)

date

2022-09-17T08:35:35Z (accessioned)

2022 (issued)

degree

Biomedical Engineering (discipline)

2027-09-06 (liftdate)

embargo

2027-09-06 (terms)

identifier

http://hdl.handle.net/10339/101245 (uri)

language

en (iso)

publisher

Wake Forest University

title

Computational assessment of posture and muscle deconditioning on kinematics and injury risk of astronauts under spaceflight loading conditions

type

Dissertation