Mission Performance Assessment of Multimode Propulsion for Satellite Servicing Applications

We assess the mission performance of a multimode (monopropellant-electrospray dual-mode) propulsion system relative to current state-of-the-art chemical, electric, and hybrid chemical-electric propulsion systems for satellite servicing applications. Performance is assessed for both low-Earth orbit servicers (with total mass of approximately 100 kg) and geosyn-chronous orbit servicers (with total mass of approximately 1000 kg). First-order spacecraft sizing routines are developed to determine spacecraft properties for each propulsion system option based on historical data, propulsion system properties, and physical and geometric constraints. The overall servicing missions are decomposed into a set of discrete maneuvers for both servicer concepts. Simulations are developed for each ma-neuver and propulsion system to determine flight performance, including ΔV and time of flight. Finally, metrics of comparison between the different propulsion system options are proposed to illustrate the strengths and weaknesses of each propulsion system option over the candidate mission scenarios. Mission scenarios are composed of admissible sequences of modeled maneuvers. Comparison metrics are then used to highlight the costs and benefits of the assessed propulsion system options relative to each other. Results indicate that the hybrid and multimode systems provide significant mission flexibility for satellite servicing applications, but the multimode does so with a significantly lower structural ratio.