Easily Replicatable Liquid Micro Pulsed Plasma Thruster
Micropropulsion devices are enabling technologies for a number of critical space missions involving all manner of spacecraft. Microthrusters can provide primary propulsion or attitude control on miniscule pico-satellites flying in tight-knit constellations. They can offer precision pointing or positioning as part of a bimodal propulsion system on conventionally scaled spacecraft. Even large space structures could be effectively manipulated via distributed systems of microthrusters. Most current thruster technology is too heavy and imprecise to satisfy the demands for these emerging space applications. Microthruster technologies that have materialized so far - such as miniature solid propellants and thermal arcjets - are grossly inefficient and operationally constrained. Furthermore, most advanced concepts under development face overwhelming technological problems. Many face fundamental barriers such as incompatibilities between propellants and materials available for device fabrication. Overcoming these problems could take millions in additional research and significantly delay their proponents from entering new space markets.
Fortunately, researchers at JHU/APL have developed a lightweight, low-power class of miniaturized pulsed plasma thrusters (PPT) for the needs of today's space industry. To date, two versions have been demonstrated, each with unique assets. A solid-state version using standard Teflon propellant yields an ultra-miniscule footprint. This device is storable indefinitely and ready for operation instantly. An alternate liquid-fueled version provides immense operating flexibility in a similarly small package. This device can employ a wide variety of liquid propellants, which can be selected to satisfy key mission criteria (e.g. minimal contamination or observables), packaged conveniently inside the spacecraft structure, and shared amongst multiple thrusters (including conventional macro-scale thrusters). Both micro-PPT versions are fabricated using inventive techniques adopted from the domain of printed circuit boards (PCB). As a result, the devices can be precisely reproduced (or mass produced) using mature and inexpensive processes. The small electrode gaps in this device permit operation at relatively low voltages. This reduces the size and weight of associated power processing electronics and wiring. However, the overall moderately-scaled device features do not necessitate the use of expensive MEMS fabrication technologies. In addition, a number of experimental laboratory technologies have been developed to help advance our understanding of these microthruster devices. These include miniaturized thrust stand systems and plasma measurement techniques. These technologies have applicability towards the further development of all manner of micropropulsion concepts.CONTACT:
Mr. E. Chalfin
Phone: (443) 778-7473