A circuit (400, 700, 800) comprising: a first power source (402) supplying first current to a load (470) during a first Period of Time (PoT); a second power source (416) supplying a second current to the load during a second POT; a Unidirectional Current Valve (UCV) in series with the first power source; a current detector (420, 702, 802) in series with the UCV (422); and a switch (424) in parallel with a series combination of the current detector and UCV to bypass the UCV during the second PoT. The current detector determines whether the second period of time has commenced and whether the switch has closed.

An electron acceleration device using thermionic fission cells and an electromagnetic scoop coil for power. A power control junction and electron injector control that feeds free electrons in packets into the acceleration components that consist of a series of induction linac module units, having quadrupole magnet units in series between the induction module units. Has on-board xenon gas for a deep space electron source. At the high speed electrons exit from the device, deflector plates control the exit path of the electrons to direct the course of a craft.

One or more embodiments relates to an air-breathing plasma thruster including a thruster wall, an anode, a cathode, and at least one ring electrode. The thruster wall defines a cylindrical channel, the cylindrical channel having a first end and an opposing second end in fluid communication with the first end, where the cylindrical channel is adapted to receive incoming airflow. The anode is at the first end of the channel and the cathode is at the second end of the channel opposite the first end. The at least one ring electrode is positioned on the thruster wall.

A dynamic flex circuit includes a plurality of hole sets arranged along the dynamic flexible circuit. The dynamic flex circuit also includes a plurality of actuator wires coupled to the dynamic flexible circuit by way of intertwining each of the plurality of actuator wires through each hole set in the plurality of hole sets arrange along the dynamic flexible circuit. Each of the plurality of actuator wires are configured to impart a motion onto the dynamic flexible circuit depending on the amount of heat applied to each of the plurality of actuator wires.

A method for controlling an ion thruster including an emission electrode, an extraction electrode and a conductive liquid which is deposited on the emission electrode, the ion thruster configured for emitting an ion beam when an electric field is applied to the conductive liquid, the ion beam providing thrust to the thruster, the thrust depending on an emission current I.sub.em and an ion emission speed, the method including the following steps: adjusting the emission current to a setpoint value I.sub.c by applying a threshold emission potential V.sub.thresh to the emission electrode by means of a current generator; and when the setpoint value I.sub.c of the emission current is reached, adjusting the emission speed by applying an extraction potential V.sub.ext to the extraction electrode by means of a voltage generator in order to bring the emission potential V.sub.em to a predetermined value V.sub.empr=V.sub.thresh+V.sub.ext.

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.

A conductive liquid-fed pulsed plasma thruster includes a first electrode having a conductive solid portion and a conductive liquid portion, a second electrode separated from the first electrode to define an ignition space therebetween, at least one electric insulator separating the first and second electrodes, and a conductive-liquid passage extending within the conductive solid portion through which the conductive liquid portion flows from an inlet to an outlet located at the ignition space. The first and second electrodes are configured so that a drop of the conductive liquid portion forms and grows at the outlet when the conductive liquid portion flows through the conductive liquid passage until the drop of the conductive liquid causes an arc discharge between the drop and the second electrode that ignites the drop to produce a plasma cloud that generates thrust when exhausted.

A device for forming a quasi-neutral ion-electron beam, including: a chamber; a set of means for forming an ion-electron plasma in the chamber; and means for extracting and accelerating charged particles from the plasma out of the chamber. The particles are capable of forming the beam and the extraction and acceleration means that include a set of at least two grids located at one end of the chamber.

A method for transferring a spacecraft (10), such as an artificial satellite, from an initial elliptical orbit (30) to a final geostationary orbit (50), the spacecraft taking at least one intermediate elliptical orbit (40) propelled by electric propulsion means (12, 13), the method includes: when the spacecraft is in an intermediate orbit, a nominal thrust step (410) in which the propulsion means generate nominal thrust while the spacecraft is on at least part of a first orbital arc (41) passing through the apogee A of the intermediate orbit, and a minimum thrust step (420), in which the propulsion means are partly stopped or slowed while the spacecraft is on at least part (43) of a second orbital arc (42) passing through the perigee P of the intermediate orbit, the two orbital arcs being complementary.

Methods and systems for estimating propellant transfer in an ion propulsion system are disclosed. One example is a method for estimating transfer of a propellant between a first tank and a second tank in an ion propulsion system during a transfer event. The first tank and the second tank are separated by a valve. A flow rate of the propellant through the valve is calculated based on an initial pressure and an initial temperature of each of the first tank and the second tank for a beginning of the transfer event, calculating, based at least in part on the flow rate, a mass of propellant transferred through the latch over a period of time ending at an intermediate time before an end of the transfer event, and determining an intermediate pressure and temperature for each of the first tank and the second tank for the intermediate time.