Development and Optimization of EVA Space Suit Ball Bearing Ferrofluid Pressure Seals and Hybrid A/X Race Geometry

Date

2020-07-31

Journal Title

Journal ISSN

Volume Title

Publisher

2020 International Conference on Environmental Systems

Abstract

Ball Bearings used by NASA, NPP Zvezda, and private aerospace corporations for space suits have not seen significant change since their inception. Plastic pressure and dust seals and two axis normal contact point designs are historically prolific, although four contact point geometries are attracting increasing interest. Problematic larger diameter bearings, such as the ones planned to be included for the shoulder, waist, and hip bearings in the new xEMU and Z-2 space suits, will particularly benefit from race and pressure seal design improvements. Four contact point geometries reduce race wear and friction over time and angled contact points improve performance in axial loading. Ferrofluid pressure seals have immeasurably low leakage, long lifetimes, and extremely low mechanical friction. They are extremely effective for sealing against typical dust particles, and have high potential for sealing against small and ferromagnetic regolith particles. This improvement would eliminate the need for many separate dust sealing systems. This thesis demonstrates the ability of these technologies to be implemented into existing EVA space suit designs while adhering to NASA regulations. This thesis also evaluates the effectiveness of various novel race and pressure seal configurations.

Description

Milo Hughes, Princeton University, US
Andrew Redd, Princeton University, US
Nikolay Moiseev, Final Frontier Design, US
ICES400: Extravehicular Activity: Space Suits
The proceedings for the 2020 International Conference on Environmental Systems were published from July 31, 2020. The technical papers were not presented in person due to the inability to hold the event as scheduled in Lisbon, Portugal because of the COVID-19 global pandemic.

Keywords

Bearing, Ball bearing, Tribology, Pressure seal, Space suit, Wear, Race, Magnets, Ferrofluid, Rotary seal, Private sector, Extravehicular activity (EVA)

Citation