Follow this link to go to the text only version of nasa.gov
NASA - National Aeronautics and Space Administration
+ Contact NASA
Go
Structures and Materials Division Research and Technology Directorate NASA Glenn Research Center

Tribology and mechanical Components Branch
Tribology and mechanical Components Home
Research Areas
Facilities
Personnel
Publications
Computer Codes
Partner with Us
Contact Information
Aero Drive Systems - Advanced Gear Systems
Research Objectives
Develop the main interface seal for the Low Impact Docking System (LIDS) which NASA is developing as the new docking system for future missions to the International Space Station, the Moon, and Mars.

LIDS main interface seal and CEV docking with ISS
 
LIDS model (top) and location on CEV (below) as it prepares to dock to the International Space Station.
 
Technical Challenges
  • Large diameter (58 in.) seals must:
    • Exhibit extremely low-leakage of less than 0.0025 lbm/day (0.001kg/day)
    • Meet extremely high reliability requirements for man-rated vehicles
    • Accommodate off-nominal conditions including gapping and axial misalignment
    • Exhibit low sealing compression and adhesion forces
    • Withstand long term exposure to the following space environments without excessive damage or loss of sealing ability:
      • Atomic oxygen (AO)
      • Ultraviolet (UV) radiation
      • Ionizing radiation
      • Micro-meteoroid and orbital debris (MMOD)
      • Vacuum conditions
      • Thermal cycling
    • Operate at temperatures from -50 C to +50 C including thermal gradients
    • Endure long mating periods (~7 months) and repeated docking

Current Research

The NASA GRC Structural Seals Team is supporting NASA JSC by developing the main interface seal for LIDS. Main activities in this effort currently include:

  • Leakage testing of seals for JSC’s 54-in. diameter Engineering Demonstration Unit (EDU 54)
  • Installation and assembly of a new test rig to evaluate full-scale seal leak rates as well as compression and adhesion loads during simulated docking and undocking
  • Fabrication of seals for JSC’s 58-in. diameter Engineering Demonstration Unit (EDU 58)
  • Seal bond integrity evaluations
  • Sub-scale seal leakage, compression, adhesion, and vibration testing
  • Long-term (e.g., 7 month) seal compression testing under vacuum
  • Impact testing of candidate seal materials to evaluate risk of MMOD strikes
54 inch diameter seal
 
Above: Close-up of 54 inch diameter seal
 
Simulated MMOD impact in candidate seal elastomer material
 
Above: Simulated MMOD impact in candidate seal elastomer material
 


+ Return to the branch research page...
Point of Contact
Pat Dunlap
Publications
View a list of published NASA reports
+ View related publications
Related Facilities
Learn more about our Aerospace Seals Facilities
+ View Facility Listing
Events
NOTE CHANGE:
NASA Seals and Secondary Flows Symposium

November 19, 2013 - Postponed to Nov. 2014 due to Government Shutdown in October. Watch for new date.

Open to OEM'S and vendors
U.S. citizens and permanent legal residents (green card holders) only

Location
Ohio Aerospace Institute Link to non-NASA website

Directions/Maps
GRC (Google Maps) Link to non-NASA website
Map to GRC (PDF)
Local food/lodging (PDF)

Download Workshop Papers
Get Adobe Acrobat Reader


MORE INFO IN NASA SITE NETWORK

+ Freedom of Information Act
+ NASA Web Privacy Policy and Important Notices
NASA - National Aeronautics and Space Administration
NASA Official: Ajay K. Misra
+ Web Curator
+ Contact NASA
Last Updated: May 5, 2009