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.

Spacecraft including a spacecraft bus. An additive manufacturing system of the spacecraft bus including at least one extruder for delivering feedstock to print an object outside of the spacecraft bus. A sensor for determining a pose of the spacecraft bus relative to an astronomical body. At least one processor in communication with the additive manufacturing system and the sensor, controls an operation of the additive manufacturing system as a function of the pose of the spacecraft bus, to manufacture the object outside of the spacecraft bus.

Methods, apparatus, and articles of manufacture to minimize command dynamics of a satellite are disclosed. An example apparatus includes a steering law module to calculate a first set of vectors to maneuver a space vehicle, and calculate a second set of vectors based on projecting the first set of vectors onto a fixed plane. The apparatus further includes an attitude controller to generate an attitude command based on the first and the second sets of vectors to prevent an unplanned rotation by the space vehicle.

A circuit for igniting and sustaining an electron discharge includes an ignitor circuit. The ignitor circuit includes a high voltage transformer and a switch connected in series between a primary of the transformer and a DC source return. The switch is configured to receive a driving signal. A reset circuit is connected in parallel to the primary of the high voltage transformer. A first rectifier is connected in series between a secondary of the high voltage transformer and a keeper. A terminal of the secondary of transformer is connected to a cathode. The circuit for igniting and sustaining the electron discharge also includes a sustaining circuit having a current source with a return connected to a cathode and a second rectifier connected in series between the current source and the keeper.

A propulsion device for vehicles, such as a spacecraft operating within a vacuum configured to ionize a fuel gas. Specifically, a soft ionization system pulls electrons from passing gas molecules directly into conductors and introduces ionized gas molecules into a static accelerating field. The ionized gas is utilized at a point of creation such that a chamber, housing, or channel to contain the ionized gas is not required.

A cusped-field thruster for a space system, wherein the cusped-field thruster comprises: at least two substantially annular permanent magnets arranged in an antipolar manner, wherein a magnetic pole piece is formed between the permanent magnets, and an anode, which comprises a permanent-magnetic material. The cusped-field thruster is configured such that a cusp is formed in a region adjacent to the anode of the cusped-field thruster.

Disclosed herein is a propulsion system comprising: a solid conductive or semiconductive cathode (130); an anode (110) having a potential difference relative to said cathode (130), said potential difference creating an electric field between said anode (110) and said cathode (130); and an insulated trigger (150) adapted to trigger an arc discharge from a point on a upper surface of said cathode (130) in pulses, when said trigger (150) and cathode (130) are substantially in a vacuum, said trigger being bounded within the cathode so that the point at which the arc is triggered is located on the upper surface of said cathode.

An orbiting satellite can be maintained in a geosynchronous orbit (e.g., with an orbital period equal to one sidereal day) at an altitude other than 35,786 km by equipping the satellite with at least one radial thruster. Radial thrusters on the anti-Earth-facing side of the satellite allow for artificial geosynchronous orbits higher than the natural altitude, while radial thrusters on the Earth-facing side of the satellite allow for artificial geosynchronous orbits lower than the natural altitude. This allows a geosynchronous satellite to evade threats, such as orbital debris and/or hostile spacecraft, without losing signal to ground based antennas. Similar techniques can also be used for surveillance of satellites in geosynchronous orbits.

A satellite propelled by laser ablation comprises: a device for managing the attitude and the orbit of the satellite; a device for capturing and potentially for processing the target spaceborne body; a device for external communication; a laser ablation propulsion device comprising one or more lasers and a module for managing the one or more lasers that is suitable for determining the one or more laser beams to be generated on the captured target spaceborne body according to the movement desired for the satellite; and a device for visually inspecting the target spaceborne body.

A Hall-effect thruster (10), configured to be arranged inside or outside a spacecraft.

The thruster has a concentrator (36) for collecting particles (P).

The shape of the concentrator is defined by a continuous contour (C1) wrapped around the thrust axis and is such that on a major portion of the contour, each section of the concentrator perpendicular to the contour has a parabolic shape and has a focus (F1) belonging to the contour (C1).

In addition, the magnetic circuit (50) is arranged so as to generate the magnetic field (B) in the vicinity of the contour (C1).