Technology development and design of liquid bi-propellant mars ascent vehicles

A notional Mars Ascent Vehicle (MAV), that could help with potential Mars Sample Return (MSR) is a very unique challenge and has been the focus of technology development and design efforts at JPL for the several years. Trajectory studies, for the current range of potential MAV payloads, evaluated performance using propulsion systems in the 2.5 kN to 4.5kN (600-1000 lbf) thrust range. The current study examined several propulsion system approaches, solid rocket, bi-propellant and hybrid propulsion systems and developed a ranking based on several key figures of merit. This paper details the trades conducted for the two bi-propellant propulsion systems considered for a potential MAV. Historically bi-propellant propulsion systems have been considered for this application, however the desire to minimize development risk resulted in solid rocket options being selected as the baseline configuration. This study takes a fresh look at both a conventional pressure fed bi-propellant propulsion system and a new technology development using a small electrically driven pump fed bi-propellant propulsion system. A detailed design and mass breakdown for both a pressure fed and a low-complexity electrically driven pump fed (EDPF) propulsion system for a potential MAV were generated. The results showed that the EDPF system although lower in technology readiness level (TRL) provided performance, mass and packaging benefits that ranked EPDF higher than a conventional pressure fed system.