Program Overview
Electrically powered plasma thrusters can provide thrust per unit mass that is orders of magnitude greater than that of chemical rocket engines. For this reason they are considered the next generation of spacecraft engines for long duration manned and unmanned space missions taking months, years, or decades. These engines are especially relevant to NASA’s planned mission to the Moon to establish a Moon base in the next few decades, and then journey to Mars.

Electric plasma engines may be used for personnel and cargo transport to establish and sustain Moon bases, and for non-transport applications such as near surface mining of the Moon, and Moon surface glazing to reduce the hazards of Moon dust.

There are two types of electric plasma engines being developed in the space science community. These are electrode-based engines for continuous operation, and pulsed electrode-less engines. Electrode based engines are subject to erosion of the electrodes at high-power levels. This limits engine lifetime and mission duration. Electrode based thrusters are also restricted to using fuels that do not corrode the electrode material. Furthermore, the high power levels in these engines require constant high voltages and currents that present unique design problems associated with the spacecraft prime power source, and with catastrophic electrical breakdown in the space environment. Pulsed electrode-less engines eliminate or greatly reduce all these problems. However, existing engines of this type are too large, heavy, and inefficient to be practical for servicing a Moon base, or for longer duration missions. Therefore, there is a need to develop practical engines of this type in the near future.

The Scientific Research Group, Radiance Technologies, and the NASA Marshall Space Flight Center are using new designs for pulsed power systems, and state of the art computer simulations of plasma dynamics to design and build a proof of principle prototype of an efficient, pulsed, electrode-less plasma thruster. This effort has been highly successful thus far, and is scheduled to conclude in March 2008 with the demonstration of a complete bench-top thruster, a new class of highly efficient pulsed power supplies, and significant advances in computer simulations of the pulsed power system and the plasma dynamics.

The project’s long-term goal is to build a prototype PPA that meets the mass, size, efficiency, and lifetime requirements for space missions.

• Developed two patentable designs for low and high energy pulsed power supplies (PPS) to power a PPA. The low energy PPS was successfully built and tested. Sub-system testing for the high energy PPS is complete. Full system assembly is nearly complete. The high energy PPS is to power the PPA that is the final project deliverable.

• Developed and tested a state of the art computer code for simulating the operation of a complete PPA for the purpose of guiding PPA design, and optimizing PPA performance.

• Radiance Technologies developed and successfully tested an alternative PPS for PPAs. This PPS is a backup to the WVHTC Foundation PPS.

• Radiance Technologies designed a new type of supersonic gas fuel feed system for PPAs based on a fast acting valve. Construction of this system is nearly complete.

• Radiance Technologies designed a new type of pre-ionizer for PPAs to increase PPA efficiency by allowing more PPS energy to be converted into thrust. Initial testing of the pre-ionizer was successful.