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Investigation of the THOR Anthropomorphic Test Device for Predicting Occupant Injuries during Spacecraft Launch Aborts and Landing.

Somers JT, Newby N, Lawrence C, DeWeese R, Moorcroft D, Phelps S - Front Bioeng Biotechnol (2014)

Bottom Line: Although all spacecraft designs were considered, the primary focus was the National Aeronautics and Space Administration Orion capsule, as the authors have the most knowledge and experience related to this design.In addition, the team down-selected the list of available injury metrics to the following: head injury criteria 15, kinematic brain rotational injury criteria, neck axial tension and compression force, maximum chest deflection, lateral shoulder force and displacement, acetabular lateral force, thoracic spine axial compression force, ankle moments, and average distal forearm speed limits.Musculoskeletal deconditioning due to exposure to reduced gravity over time can affect injury risk during landing; therefore a deconditioning factor was applied to all IARVs.

View Article: PubMed Central - PubMed

Affiliation: Science Technology and Engineering Group, Wyle , Houston, TX , USA.

ABSTRACT
The objective of this study was to investigate new methods for predicting injury from expected spaceflight dynamic loads by leveraging a broader range of available information in injury biomechanics. Although all spacecraft designs were considered, the primary focus was the National Aeronautics and Space Administration Orion capsule, as the authors have the most knowledge and experience related to this design. The team defined a list of critical injuries and selected the THOR anthropomorphic test device as the basis for new standards and requirements. In addition, the team down-selected the list of available injury metrics to the following: head injury criteria 15, kinematic brain rotational injury criteria, neck axial tension and compression force, maximum chest deflection, lateral shoulder force and displacement, acetabular lateral force, thoracic spine axial compression force, ankle moments, and average distal forearm speed limits. The team felt that these metrics capture all of the injuries that might be expected by a seated crewmember during vehicle aborts and landings. Using previously determined injury risk levels for nominal and off-nominal landings, appropriate injury assessment reference values (IARVs) were defined for each metric. Musculoskeletal deconditioning due to exposure to reduced gravity over time can affect injury risk during landing; therefore a deconditioning factor was applied to all IARVs. Although there are appropriate injury data for each anatomical region of interest, additional research is needed for several metrics to improve the confidence score.

No MeSH data available.


Related in: MedlinePlus

Thoracic spine axial compression injury risk development. (A) Relationship of DRI to operational injury data, where * denotes rocket assisted ejections (Brinkley, 1968; Brinkley and Schaffer, 1971). (B) Comparison of THOR thoracic spine axial compression to the DRI. The blue dots are individual sled tests, the solid line is the linear fit, and the dashed lines are the 95% confidence. (C) The resulting injury risk function for THOR thoracic spine axial compression force.
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Figure 9: Thoracic spine axial compression injury risk development. (A) Relationship of DRI to operational injury data, where * denotes rocket assisted ejections (Brinkley, 1968; Brinkley and Schaffer, 1971). (B) Comparison of THOR thoracic spine axial compression to the DRI. The blue dots are individual sled tests, the solid line is the linear fit, and the dashed lines are the 95% confidence. (C) The resulting injury risk function for THOR thoracic spine axial compression force.

Mentions: Currently, the BDRC is used to assess astronaut injury risk. The +Z axis model in the BDRC is also known as the dynamic response index (DRI). The DRI has been validated for predicting thoraco-lumbar spinal injury in military aircraft ejections (Figure 9A) (Brinkley, 1968; Brinkley and Schaffer, 1971). Using a base-10 log transformation, a linear fit was applied to these data to determine the relationship between DRI and injury.


Investigation of the THOR Anthropomorphic Test Device for Predicting Occupant Injuries during Spacecraft Launch Aborts and Landing.

Somers JT, Newby N, Lawrence C, DeWeese R, Moorcroft D, Phelps S - Front Bioeng Biotechnol (2014)

Thoracic spine axial compression injury risk development. (A) Relationship of DRI to operational injury data, where * denotes rocket assisted ejections (Brinkley, 1968; Brinkley and Schaffer, 1971). (B) Comparison of THOR thoracic spine axial compression to the DRI. The blue dots are individual sled tests, the solid line is the linear fit, and the dashed lines are the 95% confidence. (C) The resulting injury risk function for THOR thoracic spine axial compression force.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4126482&req=5

Figure 9: Thoracic spine axial compression injury risk development. (A) Relationship of DRI to operational injury data, where * denotes rocket assisted ejections (Brinkley, 1968; Brinkley and Schaffer, 1971). (B) Comparison of THOR thoracic spine axial compression to the DRI. The blue dots are individual sled tests, the solid line is the linear fit, and the dashed lines are the 95% confidence. (C) The resulting injury risk function for THOR thoracic spine axial compression force.
Mentions: Currently, the BDRC is used to assess astronaut injury risk. The +Z axis model in the BDRC is also known as the dynamic response index (DRI). The DRI has been validated for predicting thoraco-lumbar spinal injury in military aircraft ejections (Figure 9A) (Brinkley, 1968; Brinkley and Schaffer, 1971). Using a base-10 log transformation, a linear fit was applied to these data to determine the relationship between DRI and injury.

Bottom Line: Although all spacecraft designs were considered, the primary focus was the National Aeronautics and Space Administration Orion capsule, as the authors have the most knowledge and experience related to this design.In addition, the team down-selected the list of available injury metrics to the following: head injury criteria 15, kinematic brain rotational injury criteria, neck axial tension and compression force, maximum chest deflection, lateral shoulder force and displacement, acetabular lateral force, thoracic spine axial compression force, ankle moments, and average distal forearm speed limits.Musculoskeletal deconditioning due to exposure to reduced gravity over time can affect injury risk during landing; therefore a deconditioning factor was applied to all IARVs.

View Article: PubMed Central - PubMed

Affiliation: Science Technology and Engineering Group, Wyle , Houston, TX , USA.

ABSTRACT
The objective of this study was to investigate new methods for predicting injury from expected spaceflight dynamic loads by leveraging a broader range of available information in injury biomechanics. Although all spacecraft designs were considered, the primary focus was the National Aeronautics and Space Administration Orion capsule, as the authors have the most knowledge and experience related to this design. The team defined a list of critical injuries and selected the THOR anthropomorphic test device as the basis for new standards and requirements. In addition, the team down-selected the list of available injury metrics to the following: head injury criteria 15, kinematic brain rotational injury criteria, neck axial tension and compression force, maximum chest deflection, lateral shoulder force and displacement, acetabular lateral force, thoracic spine axial compression force, ankle moments, and average distal forearm speed limits. The team felt that these metrics capture all of the injuries that might be expected by a seated crewmember during vehicle aborts and landings. Using previously determined injury risk levels for nominal and off-nominal landings, appropriate injury assessment reference values (IARVs) were defined for each metric. Musculoskeletal deconditioning due to exposure to reduced gravity over time can affect injury risk during landing; therefore a deconditioning factor was applied to all IARVs. Although there are appropriate injury data for each anatomical region of interest, additional research is needed for several metrics to improve the confidence score.

No MeSH data available.


Related in: MedlinePlus