A Review of the Rubicon Space Systems 5N Low Throughput ASCENT Thruster Development

The Propulsion division of Plasma Processes LLC was relaunched as Rubicon Space Systems with a mission to commercialize its line of thrusters and develop a line of propulsion systems for the small satellite industry. Rubicon\u27s thrusters and propulsion systems use ASCENT monopropellant, also known as AF-M315E, developed by AFRL enabling high performance and safer chemical propulsion technology alternative to hydrazine and other green propellants. With more than 30 years of combined experience in green propulsion and thousands of hours of thruster testing experience, Rubicon leads the world in the development and commercialization of ASCENT propulsion technology

Sprite, A Modular Template of In-Space Propulsion

Huntsville, AL is home to Plasma Processes, a materials company that creates high temperature material solutions for aerospace and defense applications. Their capabilities include several thermal spray coating techniques, near-net shape refractory metal fabrication, and an array of government and commercial customer entities. A Small Business Innovation Research (SBIR) contract received in 2016 pushed the development of Plasma\u27s first fully integrated thruster assembly using component processes for thrust chambers, injector heads, and high temperature parts that Plasma creates daily for various entities. The thruster assembly used the ASCENT, or AF-M315E, propellant, which was first demonstrated on the Green Propulsion Infusion Mission (GPIM) that featured thrust chambers made by Plasma Processes. Plasma\u27s SBIR thruster assembly gained the attention of a NASA flight project after demonstrating the viability of the thruster. In 2021, twelve thrusters were delivered to the Lunar Flashlight mission, of which four thrusters launched in December 2022. The successful development of the 0.1N thruster thruster was a catalyst for new developments and growth. Rubicon Space Systems, a division of Plasma Processes LLC, was formed in mid-2022 to become the premiere manufacturer of ASCENT thrusters and propulsion systems. In development since early 2022, the Sprite propulsion system is a 1.5U fully enclosed, plug-and-play solution for SmallSats. Sprite targets missions in need of space propulsion collision avoidance, and de-orbit capabilities while providing over 1200 Ns of total impulse, the equivalent of 100 m/s of delta V to a 12U CubeSat. The system utillizes the green monopropellant ASCENT, or AF-M315E, to improve system performance and reduce propellant handling costs when compared to other industry-standard monopropellants. Sprite features a flight qualified 0.1N with space heritage, a fully integrated flight controller, heritage components such as valves that have been demonstrated on previous missions, and a fully additively manufactured structure. Commands and telemetry are transmitted over RS-422 to the spacecraft, and RS-485 communication allows up to 8 modules to be networked together for systems that require multiple thrusters. The Sprite propulsion system passed its Critical Design Review (CDR) in December 2022 and its first four engineering development units (EDUs) are expected to complete qualification efforts in Q3 2023. A Protoflight article will be delivered to NASA in Q1 of 2024

Preparing CySat-1: A look at Iowa State University’s first CubeSat

In this paper, an overview of the scientific mission of CySat-1, the derived vehicle requirements, impact on system design, and the educational opportunities presented by these challenges. CySat-1, previously scheduled for launch on the SpaceX-21 and awaiting further details following the COVID-19 pandemic, is a CubeSat designed and built by students at Iowa State University. The primary mission of CySat-1 is to provide hands-on experience to undergraduate students in designing, building, and testing a space system. CySat-1 also hosts a scientific payload, a software-defined radio (SDR) radiometer, to survey soil moisture content on Earth from Low Earth Orbit. This mission further reinforces the affordability of CubeSats for future research missions. The Iowa State University CubeSat, CySat-1, was selected for NASA’s CubeSat launch initiative (CSLI) program and will be launched with a future ELaNa mission. The operation will be for three to six months after the deployment from the International Space Station. We will discuss the overall function of the payload and how we integrated the payload into the CubeSat. This discussion will include the student-initiative design and fabrication of critical components, including the payload and CubeSat structures. CySat-1 augments in-house, student designs with commercial off-the-shelf (COTS) components, creating a real-world integration challenge. Iowa State University’s first CubeSat program spurred the installation of facilities such as a clean room with the anti-static capability to support building, testing, and integration of delicate space hardware. Through this process, students acquired experience with industrial level integration and testing procedures. Undergraduate teams working on CySat-1 lead the design and fabrication of the payload, structure, and system integration, providing experience with systems engineering, technical writing, and various cross-disciplinary applications. Over sixty undergraduate students, several graduate students, and four faculty members from multiple departments worked on the development of this CubeSat under the Make to Innovate program at Iowa State University, which engages students in various projects to augment their understanding of engineering fundamentals

Development of ASCENT Propellant Thrusters and Propulsion Systems

Since the 1960s, hydrazine technology has dominated the market of propulsion technology by providing reliable performance on a wide variety of spacecraft. Efforts to replace hydrazine with a higher-performance and safer alternative have engaged numerous emerging technologies in the industry to mature. ASCENT propellant, also known as AF-M315E, is an example of one such green propellant. Initially developed to provide a safer handling environment than hydrazine, ASCENT offers higher overall performance than a hydrazine equivalent by creating more heat during ignition. The next generation of propulsion technology, based on ASCENT propellant, produces a higher impulse and energy density, expanding the realm of applicable missions from LEO to GEO and beyond. Building on a strong background in small satellite technology and expertise in thermal and oxidation resistant materials, Plasma Processes began several thruster programs for variety of small satellite applications using ASCENT-based technology. Plasma Processes’ background expertise in thermal and oxidation resistant materials provides the necessary foundation to create ASCENT-based technology hardware