title: Assessing astronaut injury potential from suit connectors using a human body finite element model.
abstract: BACKGROUND
  The new Orion space capsule requires additional consideration of possible injury during landing due to the dynamic nature of the impact. The purpose of this parametric study was to determine changes in the injury response of a human body finite element model with a suit connector (SC).
  
  
  METHODS
  The possibility of thoracic bony injury, thoracic soft tissue injury, and femur injury were assessed in 24 different model configurations. These simulations had two SC placements and two SC types, a 2.27-kg rectangular and a 3.17-kg circular SC. A baseline model was tested with the same acceleration pulses and no SC for comparison. Further simulations were conducted to determine the protective effect of SC location changes and adding small and large rigid chest plates. The possibilities of rib, chest soft tissue, and femur injury were evaluated using sternal deflection, chest deflection, viscous criterion, and strain values.
  
  
  RESULTS
  The results indicated a higher likelihood of chest injury than femur injury. The mean first principal strain in the femur was 0.136 +/- 0.007%, which is well below the failure limit for cortical bone. The placement of chest plates had a protective effect and reduced the sternal deflection, chest deflection, and viscous criterion values.
  
  
  CONCLUSIONS
  If possible, the SC should be placed on the thigh to minimize injury risk metrics. Chest plates appear to offer some protective value; therefore, a large rigid chest plate or similar countermeasure should be considered for chest SC placement.
authors.affiliation: Virginia Tech/Wake Forest University School of Biomedical Engineering, Winston-Salem, NC 27157, USA.
authors.forename: Kerry A
authors.initials: KA
authors.lastname: Danelson
authors.forename: John H
authors.initials: JH
authors.lastname: Bolte
authors.forename: Joel D
authors.initials: JD
authors.lastname: Stitzel
mesh_terms: D000054:Acceleration; D018480:Astronauts; D001696:Biomechanical Phenomena; D020342:Finite Element Analysis; D006801:Humans; D008021:Life Support Systems / Q000295:instrumentation; D018570:Risk Assessment; D019442:Space Suits; D013314:Stress, Mechanical; D013898:Thoracic Injuries / Q000209:etiology*