CU Aerospace (CUA) proposes the development of the Quick Turn Pulsed Plasma Thruster (QT-PPT) with 2400s 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 several electronics subsystems including high-density energy storage via MLCC capacitors (life tested), low erosion discharge geometry, regenerative carbon igniters with negligible erosion, compact power electronics, and electromagnetic thrust vectoring. QT-PPT seeks to further the miniaturization of the subsystems, but with a 70g Teflon disc (no fiber). In this Phase I, CUA will leverage the technology improvements from FPPT to build a more accessible QT-PPT system with lower size, weight, power, and cost (SWaP-C). The entire system including 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. The proposed technology is estimated to have a specific impulse of 2400s and a total impulse of 1640N-s, enough to lower a 5 kg CubeSat from 1000 km to 400 km. The total impulse can be increased with additional volume and fuel loading if desired for deorbiting larger CubeSats. CUA’s thrust vectoring technology is slated for integration into the system during the Phase II effort, relieving requirements for separate attitude control systems that may be difficult for small missions to meet. CUA’s long term goal will be to establish the QT-PPT as a mature integrated system solution with standard lead times under 6 weeks. One QT-PPT will be delivered to NASA at the end of the Phase II program.
The practice of responsible space and deorbit capability of LEO satellites is critical for the prevention of an escalation of space debris. With an anticipated 1640N-s total impulse from a 0.5U QT-PPT system, deorbit from 1000 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.