Study of the Performance of Propulsion Units with Nitrogen-Jet Thrusters for Astronaut Extravehicular Activities’ (EVAs)

The future plans of the space agencies all across the globe, mainly focus on the advance of the Extravehicular Activities (EVAs) that are orientated in the repair and maintenance of the space vehicles. This thesis presents a brief history of the space suits (EMU, Orlan-M) utilized in space applicati...

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Bibliographic Details
Author: Monokrousos, Nikolaos
Format: master thesis
Publication Date:2021
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/360770
Online Access:https://hdl.handle.net/2117/360770
Access Level:Open access
Keyword:Outer space--Exploration
Astronautics
Propulsion systems
Astronauts
Extravehicular Activity
Simplified Aid for Extravehicular Activity Rescue
SAFER
nitrogen-jet thrusters
spacewalking
Espai exterior--Exploració
Astronàutica
Sistemes de propulsió
Astronautes
Àrees temàtiques de la UPC::Aeronàutica i espai::Astronàutica
Description
Summary:The future plans of the space agencies all across the globe, mainly focus on the advance of the Extravehicular Activities (EVAs) that are orientated in the repair and maintenance of the space vehicles. This thesis presents a brief history of the space suits (EMU, Orlan-M) utilized in space applications and the propulsion units (Hand-Held Maneuvering Unit, Manned Maneuvering Unit and the Simplified Aid for Extravehicular Activity Rescue-SAFER which is currently being used for performing self-rescue maneuvers, in the case the EVA crew member becomes untethered from the orbiter) that have been used during the space activities. After introducing the space environment and the critical conditions that surround the astronaut during these activities, the fundamentals of the Cold Gas Propulsion Systems on which the function of the SAFER propulsion unit is based, are presented. The aim of this thesis is to perform a performance analysis of the SAFER propulsion unit, with the extraction of the basic space propulsion concepts, i.e. thrust, specific impulse, etc. and the verification of the produced results with the technical characteristics of the unit. The orbital dynamics applying on the astronaut during an EVA are also being studied in this thesis, starting from the scenario where the crew member becomes untethered and floats freely in the vacuum of space and at the same time, examining the case where the SAFER propulsion unit is being activated for the performance of the self-rescue maneuver, and the return of the astronaut to the orbiter.