Thruster grid clear circuits and methods to clear thruster grids are disclosed. An example apparatus includes a low voltage grid clear circuit to apply first energy to a grid at a first voltage, and a high voltage grid clear circuit to detect a failure of the applied energy to clear a short circuit condition of the grid and to apply second energy to the grid at a second voltage higher than the first voltage.

A gas inlet (10), in particular for use in an ion thruster, comprises a housing (12) which is made of a gas-tight ceramics material and which is provided with a first gas feed channel (14) and a second gas feed channel (16) arranged downstream of the first gas feed channel (14). The gas inlet (10) further comprises an insert (18) which is arranged in the second gas feed channel (16) and is made of a porous ceramics material, wherein the geometry and pore structure of the insert (18) are such that the insert (18) forms a desired flow resistance for a gas stream flowing through the second gas feed channel (16) which is greater than a flow resistance acting on a gas stream flowing through the first gas feed channel (14), and wherein a ratio of a length (11) of the first gas feed channel (14) to a length (13) of the insert (18) is at least 1:2.

A conduit is placed between a vacuum system and the open air or other gaseous environment. A laser or other excitation source is used to ionize the air on the air-side of the conduit. An axial applied electric field is used to repel positive ions from traversing the tube and reaching the region of the vacuum. Electrons are collected in the vacuum region and disposed of using a Faraday cup. The repelled ions assist in creating a counter pressure to sweep neutral atoms out of the tube and back into the ambient air. As a result, a hollow tube can connect an evacuated volume to the open air without compromising the vacuum. This is a windowless window. An array of such tubes can be assembled together to increase the area of the aperture.

A thrust producing system includes an RF ion thruster with a discharge chamber having a gas inlet and an outlet, and a coil about the discharge chamber. The system further includes an RF cathode proximate the discharge chamber outlet of the RF ion thruster for ion beam neutralization. The RF cathode includes a discharge chamber having a gas inlet and an outlet and a coil about the discharge chamber. A tank for containing iodine in solid form and a heater associated with said tank to produce iodine vapor. A feed subsystem fluidly couples the tank with the RF ion thruster discharge chamber gas inlet and with the RF cathode discharge chamber gas inlet.

An electric ion propulsor and method of using is provided comprising a substrate having an inner surface and outer surface. A plurality of antennae mounted adjacent to each other on the inner surface and are enabled to transmit RF energy, and a controller having a connection to each of the plurality of antennae, a digital signal processor (DSP) and software stored in memory enabling control of transmission of the RF energy by each of the plurality of antennae. The antennae are subdivided into a plurality of arrays, a first array of the plurality of arrays serves to ionize ambient air and trap the resulting ionized air into a plurality of individual voxels and each voxel is transferred to another adjacent array, subsequently and in a linear direction, until the voxel exits the substrate at a speed enabling air movement causing thrust.

The present disclosure relates to the technical field of space electric propulsion of spacecrafts, and discloses a thrust-quantitatively-controllable and self-neutralizable Kaufman ion thruster and a use method thereof. The Kaufman ion thruster includes a discharge chamber, a central cathode, a gas supply assembly, a steel magnetic assembly, an insulating barrier and a grid system, wherein the central cathode is coaxially inserted in the center of a front panel; the gas supply assembly includes an electronegative working substance gas source, a conventional working substance gas source, N electronegative working medium gas supply pipes and N working medium gas supply pipes; the insulating barrier includes a central connecting rod and 2N fins. Self-neutralization can be achieved without the need of neutralizers. In addition, the center-oriented thrust modes can be used for spacecraft orbit control; and the eccentric thrust mode can be used for spacecraft attitude adjustment.

An ion thruster, comprising: a discharge chamber for accelerating ions towards one direction; an inflow opening for intake of a propellant into the discharge chamber; a discharge cathode, shaped in a form of a propeller, for releasing electrons in the discharge chamber, thereby ionizing the propellant in the discharge chamber, wherein the discharge cathode is rotatable around an axis, thereby propelling inward to the discharge chamber the propellant thereof; an outflow opening for exhausting the ions from the discharge chamber; and an accelerator electrode, shaped in a form of a propeller, for accelerating the ions towards the one direction of the outflow opening, wherein the accelerator electrode is rotatable around an axis, thereby propelling outward from the discharge chamber the ions and neutral atoms thereof; wherein the ion thruster comprises electromagnetic coils for generating a magnetic field inside the discharge chamber.

A plasma motor for extracting a positive ion flow has a single ionization stage and a device for supplying the ionization stage with an ionizable electronegative gas. The plasma motor further has a device for creating an electric field so as to produce the ionization of the gas in the ionization stage. The device for creating the electric filed includes a device for extracting a negative ion flow and, a device for extracting a positive ion flow, connected to the ionization stage. The extraction of a positive ion flow and the extraction of a negative ion flow are of the same amplitude, ensuring the electrical neutrality of the motor. The extraction of a positive ion flow and the extraction of a negative ion flow allow the neutrality of the motor to be ensured.

An apparatus generates energetic particles and generates a plasma of a vaporized solid material and gaseous precursors for the application of coatings to surfaces of a substrate by way of condensation of plasma and for electric propulsion applications.

Provided is a C/C composite that reduces weight when used in an ion engine grid and makes it possible to achieve high levels of both erosion resistance and machinability. A C/C composite for use in an ion engine grid is formed from a completely spread-type carbon fiber nonwoven fabric, and the carbon fibers constituting the carbon fiber nonwoven fabric are pitch-based carbon fibers.