This past week, my brother Jason and I were fortunate enough to be allowed to sit in on a guest lecture at the University of Colorado Engineering Center by NASA Astronaut Joe Tanner. Joe spoke to us about the ins and outs of spacesuit design, and shared a bunch of his personal stories. A pic or two, as well as my brief notes:

Space Habitat Design  – ASEN 5158

Notes

• Main challenges of EMU – refurbishment of the suit after every flight.
• Now on ISS, suits left on station for a long time – like 6 months. modular components
• EMU – on extended EVA’s, it’s necessary to resupply suit halfway through – takes 5 minutes minutes to refil o2.
• Limiting consumable on EMU is the co2 scrubbing system
• After Ed White’s gemini EVA, training focus was switched to underwater training
• Apollo EVAs
  • Umbilical based
  • to pick up film from outside of module
  • no cooling system
  • Backpack – SOP – Secondary o2 pack
• Apollo Lunar walk SOP
  • Very high center of gravity because of high location of SOP
• STS
  • SAFER – cold gas jet mechanism for navigating in space.
• Suited Environments
  • Launch, Entry and Abort – must be able to operate flight controls, as well as emergency depress/egress
  • Orbital – shirts and shorts, unless on TV, then nasa wants the astronauts to wear long pants.
  • Lunar/Mars – main concern is the dust – will eat the suit alive!
  • NEO’s – Biggest problem is body stabilization
• Suit Functional Requirements
  • Environmental control and live support parameters
    • Maintain Pressure
    • Remove co2
    • Provide o2
    • thermal control
    • humidity control
    • trace contaminant control
    • mmod/radiation protection
    • food/water
      • water is space suit is tube with actual bite valve from Camelbak
    • waste
    • mobility/dexterity
• ORLAN Russian Spacesuit
  • In use for 40+ years, still in use today. Pressurized at 5.7 psi suit, which makes an easier transition from cabin to eva, but makes hand dexterity more difficult.
• Delta p Concerns
  • Getting from cabin pressure to suit pressure – issues include decompression sickness, bends, etc
  • Prevented by lowering cabin pressure, lowering N2 content in atmosphere, or lowering n2 content in human.
  • Prebreathe protocol – facilitate equilibrium
  • Zero prebreathe is at 8.3 psi
• Haldane’s Ratio – Defines cabin/suit pressure ration based on risk of DCS