Various Improvements to the Design of `Liquid Micro Pulsed Plasma Thrusters`

Reference#: P02125

Pulsed Plasma Thrusters (PPT) currently designed employ springs or other mechanical devices to convey or advance a solid fuel bar. These mechanical devices can be very difficult or impractical to use on very small scales. The relatively large size of the current PPTs limits how small each propulsion pulse can be The current PPTs have a limited fuel capacity, reducing their operating duration.

APL has pioneered the development of innovative micro pulsed plasma thrusters that consume non-hazardous liquid propellants, such as water. Furthermore, APL has developed a technique for fabricating these propulsive structures using inexpensive printed circuit boards (PCB) techniques. The APL design reduces the size of the PPT and allows finer increments of propulsion pulses. This makes the APL PPT design particularly suitable for small satellite applications and for ultra precise station keeping applications.

Pulsed plasma thrusters use an electric discharge to ionize and accelerant their propellant. A combination of thermal expansion and electromagnetic acceleration can be used to accelerate the propellant to extremely high velocities. This imparts more momentum to the spacecraft while using propellant efficiently. Moreover, these thrusters are less complicated than other electric propulsion devices and require less structural and electronic overhead.

Micropropulsion devices require specialized instruments and techniques for interrogating their performance. APL has led the development of miniature thrust stands and Langmuir probes to advance the state of micro PPT technology. These instruments are capable of high frequency measurements necessary to track the behavior of these unsteady devices.

Patent Status: U.S. patent(s) 7530218 issued.

Dr. G. R. Jacobovitz
Phone: (443) 778-9899

Additional References:

Link to U.S. Patent and Trademark Office