93-182
Parametric Studies And Orbital Analysis For An Electric Orbit Transfer Vehicle Space Flight Demonstration
Edward R. Avila*
Abstract
The Electric Insertion Transfer Experiment (ELITE) is an Air Forco Advanced Technolosy Transition Demonstration which is boing executed as a cooperative F;ss arch and Development Agreement between the Phillips Lab and TFtllV (ret, 1). Th- objectiv- is to build, test, and fly a solar-electric orbit transfer and orbit maneuvarln~ vahicle, €5 8 precursor to an operational eiectric orbit transfer vehicle (EOT\/). EOTV misslon planners must have knowledge of the effects of operating a vehicle in a low-thrust, spiral trajec- tory Some o~ these e~ects include gravity losses, atmospheric drag, solar occultation, and radiation damage to solar arrays. As various system components conUnue to be proposed and evaluated for the ELITE spacecraft, it has been important for mission plan- ners to have enicient tools capable of modeling different electric propulsion systems and mission parameters. This paper surveys some of the analysis tools usod to do parametric studies and discusses the study results. The primary analysis tool was the Electric Vehicle Analyzer (EVA) developed by the Phillips Lab and modified by The Aarospace Corporation It uses a simple orbit averaging approach to model low-thrust transfer per-tormance and runs in a PC environment. The assumptions used in deriving the EVA math model are presented. This tool and others surveyed were used to size the solar array power required for th- spacecraft, and develop a baseline mission protile that meets the requirements ot the ELITE mission.
*U.S. Air Force Phillips Lab. Syslem Engineer. Dr. Avila represents the Lab. at TFI\IV, F~edondo Beach, California.