Modeling and simulation of permanent on-orbit servicing infrastructures dedicated to modularized earth-orbiting platforms

This research aims to quantify the responsiveness and cost-effectiveness of permanent on-orbit servicing (OOS) infrastructures providing services to multiple serviceable platforms in coplanar medium Earth orbit (MEO) and/or geostationary orbit (GEO). The customer satellites are assumed to be made of elementary units (EUs). EUs are small standardized structural units capable of aggregating with each other and gathering the key functions of a typical satellite within the size of a 6U cubesat. Two OOS infrastructures are modeled in this research. The first one, called “Without depot” (WoD), includes a launch vehicle and a robotic servicer. The second infrastructure, called “With Depot” (WD), includes a launch vehicle, a robotic servicer and an orbital depot of EUs. This research is divided in two parts. The first part quickly developed a Simulink-based event-driven simulation framework to compare the responsiveness of WoD and WD, and provide some insight into their respective cost-effectiveness. The metrics used to quantify responsiveness for this first study are the service completion rate and the average waiting time before an EU is replaced over a 10-year period of operation. It is shown that WD is more responsive thanWoD but is also likely to be more expensive to run. Based on this observation, the second part of this research developed a Python-based event-driven simulation framework capable of capturing a much larger trade space of the WD infrastructure than the Simulink framework does. The Python framework considers more accurate models and includes much more OOS design features, such as the number of servicers, more efficient service dispatch strategies and new space trajectories. For this second study, responsiveness is measured via the average working state of the population of customer satellites, which captures how well the satellites work based on three different failure severities and the number of failures. Cost-effectiveness is measured thanks to the average mass sent to orbit per year required to efficiently run the OOS infrastructures. It is first shown that there exist designs based on propellant optimal trajectories yielding similar levels of responsiveness as designs using Lambert-trajectory-based propellant-time-traded trajectories but at much lower costs. The second conclusion is that finding responsive and cost-effective OOS designs is not intuitive. This has to be done through an exhaustive exploration of the trade space of OOS, given the high number of design variables. This research si believed to be a critical milestone in the design of a responsive integrated space infrastructure dedicated to the development and prosperity of a new GEO/MEO economy.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Aerospace Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2017

Author dc:creator

• Sarton Du Jonchay, Tristan

Contributors dc:contributor

• Ho, Koki

• On-orbit servicing
• Satellite modularization

Statement dc:rights

• Copyright 2017 Tristan Sarton du Jonchay

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/97510

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/97510