Low thrust transfer of Large Space Systems

A study which defined an optimized low-thrust orbit transfer vehicle (OTV) is presented. The objectives of this NASA study were to (1) characterize missions which require or benefit from low-orbit transfer; (2) evaluate and compare candidate low-thrust liquid propulsion orbit transfer vehicle concepts; (3) determine propulsion/system characteristics which have the greatest influence on system suitability/capability; and (4) identify and describe propulsion technology requirements. A computerized optimization procedure was developed to determine the effect of thrust level and transients, number of burns, and payload structure material; a baseline hydrogen/oxygen low thrust OTV configured specifically for orbit transfer of large space systems was defined. Finally, the requirements for the engine for an optimized low thrust stage and the optimum vehicle for low acceleration missions were specified.