Innovative Modular Propulsion for Multi-Mission Space Vehicles

ABSTRACT: This program develops a Modular Propulsion system design and demonstration test bed that continues the efforts of the Phase I program that established the feasibility of a green propellant based modular propulsion system. Two reduced toxicity propellants will be considered: LMP-103S and AFM-315E. The mission type and the spacecraft size strongly impact the details of the modular propulsions design such as the number and size of thrusters to be used. Small 1-N thrusters best suited for attitude control activities while thrusters like the 5-N and 22-N thrusters with their more efficient use of propellant are better suited for high delta-V maneuvers. A modular propulsion housing will provide a stable mounting platform for tanks, valves, thrusters, plumbing, etc. A Gen 3 ASIM will be developed that allows the whole propulsion system to be commanded as a single device. The ASIM will be commanded by a Propulsion Activity Agent that can take a time referenced position and velocity command and compute the thrust vector and total impulse required. A brassboard test bed will be created that incorporates the structure, ASIM, Propulsion Activity Agent, our spacecraft simulation with HWIL capability, associated xTEDS, and propulsion components such as valves, transducers, piping, and tanks. BENEFIT: Development of a green modular system provides the small satellite industry with more capable missions. The use of propulsion on small platforms can be prohibitive because of overall cost and propellant handling restrictions. The combination of a modular approach coupled with higher energy density and green aspects of either HPGP or AFM-315E can address both of these issues making propulsion enabled small satellites more viable for a wider user and mission type base, e.g., DoD, NASA, commercial space (both domestic and international), university sponsored programs. Additionally, such a product type complements rideshare opportunities such as ESPA. For example, ESPA-class satellites will be able to take advantage of lower cost access to space, but can have the ability to modify their orbits since they are enabled with meaningful propulsion capability.