A thruster has a first stage and a second stage. The first stage is a plasma source that outputs a plasma. The second stage is an accelerator. In one embodiment, the second stage is a plasma accelerator that accelerates the plasma. In another embodiment, the second stage is an ion accelerator that accelerates the ions from the plasma.

A polarity-selectable high voltage direct current power supply including a first drive assembly that transforms a first low voltage DC input into a first medium voltage alternating current output; a first HV output assembly that transforms the first LV AC output into a first HV DC output, wherein the first HV output assembly defines a first input stage; a polarity selector coupled between the second output junction of the first drive assembly and the first and second input stages of the first HV output assembly, the polarity selector operable between a first configuration and a second configuration; wherein in the first configuration the first HV DC output has a positive polarity; and wherein in the second configuration the first HV DC output has a negative polarity.

A blower/fan for the purpose of greatly reducing noise levels and extending longevity over conventional blade-based blower/fans (e.g., 50 decibel leaf-blower), due to having a totally novel absence of moving parts, such as motor and blades, which create most of the noise and wear out faster. The air motivating force comes from an electrohydrodynamic ionic wind created by a very strong electric field crossing two uniquely configured electrodes. This wind is then further amplified by inducing outside air to be added to this wind by means of a Coand surface at the entrance to the wind tunnel and which then feeds over a slit. A diffuser section follows causing the wind pressure to build for improving the exiting air characteristics. The novel diffuser and Coand surfaces will have reduced drag and noise due to both a low friction surface coating and a dimpled surface like a golf ball so as to further reduce drag.

Electroaerodynamic devices and their methods of operation are disclosed. In one embodiment, ions are formed by dielectric barrier discharge using a time varying voltage differential applied between a first electrode and a second electrode. The ions are then accelerated in a downstream direction using a second voltage differential applied between a third electrode and the first and/or second electrodes, where the third electrode is located down stream from the first and second electrodes. The ions may then collide with naturally charged molecules and/or atoms within a fluid to accelerate the fluid in the downstream to create an ionic wind and an associated thrust.

The present disclosure relates generally to thrust vector control mechanisms. Mechanisms are provided comprising support and attachment members for securing a thruster or other object to an additional object and wherein the thruster or object is provided with freedom of movement. At least one motor is provided to control movement and positioning of a thruster or similar object.

Propulsion systems, such as electrospray thrusters, may include an electrically actuated valve to permit a selective flow of propellant to a thruster. The valve may be located and arranged such that it physically separates a propellant, such as a source of ions, from a thruster of the propulsion system. In some embodiments, the application of a voltage potential to the valve may wet a plurality of through holes formed in the valve with the propellant such that the propellant flows through the valve to the thruster. After the valve has been opened, the propulsion system may be operated normally.

A thruster has a first stage and a second stage. The first stage is a plasma source that outputs a plasma. The second stage is an accelerator. In one embodiment, the second stage is a plasma accelerator that accelerates the plasma. In another embodiment, the second stage is an ion accelerator that accelerates the ions from the plasma.

A polarity-selectable high voltage direct current power supply including a first drive assembly that transforms a first low voltage DC input into a first medium voltage alternating current output; a first HV output assembly that transforms the first LV AC output into a first HV DC output, wherein the first HV output assembly defines a first input stage; a polarity selector coupled between the second output junction of the first drive assembly and the first and second input stages of the first HV output assembly, the polarity selector operable between a first configuration and a second configuration; wherein in the first configuration the first HV DC output has a positive polarity; and wherein in the second configuration the first HV DC output has a negative polarity.

A control device includes an acquiring unit and a processing unit. The acquiring unit acquires a voltage course and a current course of a determinable number of periods of a frequency generator and transmits these to the processing unit. The processing unit determines a temporal offset t.sub.1 between a rising edge of the current course and a rising edge of the voltage course for each period of the determinable number of periods, and further determines if this temporal offset t.sub.1 is positive or negative. The processing unit determines a difference between the number of periods with positive temporal offset and the number of periods with negative temporal offset within the determinable number of periods, and generates and adapts a switching signal for a switch-on time of the voltage course if the number of periods with positive temporal offset differs from the number of periods with negative temporal offset.

A propulsion apparatus for space vehicles, includes a solid state oxygen-rich source layer, means for extracting oxygen from said solid state oxygen-rich source layer, means for accelerating correspondingly extracted oxygen ions into vacuum. A stack includes the solid state oxygen-rich source layer, an active layer being deposited above the solid state oxygen-rich source layer, in contact with the solid state oxygen-rich source layer, the active layer being formed with a material different from the solid state oxygen-rich source layer, the material being an oxide presenting impedance hysteresis behavior.