Conceptual design of gateway based space tug using hybrid propulsion

Abstract

This thesis introduces the study on the conceptual design of a space tug that executes missions based on the Lunar Orbital Platform-Gateway. The mission for the space tug has been defined so that it can transport lunar lander/orbiter from the Gateway to low lunar orbit. Functional requirements for the tug have been derived from the mission, which were used to design its subsystems. A hybrid propulsion system, which is composed of the chemical propulsion and the electric prolusion, is considered to utilize their advantages. A design optimization problem for the space tug using the hybrid propulsion and a solution procedure to effectively solve the problem have been proposed. A comprehensive case study for design of a space tug and associated trajectories and the sensitivity analysis with respect to the change in the payload mass have been conducted.