CU Aerospace (CUA) proposes the further development of the Quick Turn Pulsed Plasma Thruster (QT-PPT) in configurations up to 3200s specific impulse that will provide CubeSat deorbit capability at end-of-life for LEO missions. While classic PPT technology is mature, it has historically been limited by its size and propellant load. CUA developed the Fiber-fed PPT (FPPT) and developed miniaturized electronics subsystems including life-tested high-density energy storage via MLCC capacitors, low-erosion discharge geometry, negligible-erosion regenerative carbon igniters, compact power electronics, electromagnetic thrust vectoring, and high-performance filament feed of non-toxic solid Teflon propellant. QT-PPT Phase I sought to further the miniaturization and simplification of the subsystems specifically energy storage and fuel feed. In this Phase II, CUA will leverage the prior work to build a QT-PPT system with lower size, weight, power, and cost (SWaP-C). The entire system including the PPU is tightly integrated onto a stack of PCBs approximately 0.5U in size, which offloads most of the manufacturing and quality control to the specialized PCB manufacturer, and enables the Quick Turn PPT system integrated by CUA. Recent FCC deorbit rule changes require more total impulse than was anticipated at the onset of Phase I, but QT-PPT with a fiber feed system can achieve a full 2000 km deorbit for a 12 kg spacecraft from a 0.7U thruster. The total impulse can be varied via fuel loading and capacitor energy selection, and thrust vectoring is also an option. For comparison, the baseline 0.5U configuration is estimated to have a specific impulse of 1400s and a total impulse of 1700N-s, enough to lower a 5.5 kg CubeSat from 1000 km to 400 km. CUAs long-term goal will be to establish the QT-PPT as a mature integrated system solution with standard lead times under 6 weeks. One flight-like QT-PPT will be delivered to NASA at the end of the Phase II program. Anticipated
Benefits: The practice of Responsible Space and deorbit capability of LEO satellites is critical for the prevention of an escalation of space debris. Deorbit from up to 2000 km is possible at end-of-life with only power and attitude determination available from a CubeSat to guide the thrust-vectored propulsion system (no reaction wheels or magnetorquers required). Unlike drag-based deorbit systems, QT-PPT also provides an as needed collision avoidance option for the entire mission. Commercial interest in nano-/small-satellites continues to grow, and it is more important than ever that these satellites have access to a technology for end-of-life deorbiting. The QT-PPT provides a compact, light-weight, non-hazardous, high total impulse propulsion technology solution available in a family of sizes to meet the differing mission needs of users in DOD/industry/academia.