Abstract: Disclosed is a space cold gas thruster operating with a solid propellant. The cold gas thruster includes a tank suitable for containing a solid propellant and a tank heating device suitable for sublimating the solid propellant and forming gaseous propellant, the tank having an aperture for transferring the gaseous propellant outside the tank, such as a nozzle. Also disclosed is a process for determining the amount of remaining propellant in the propellant tank of the disclosed cold gas thruster.

Abstract: Disclosed is a radio-frequency plasma generating system including a radio-frequency generator and a plasma source, the radio-frequency generator being inductively or capacitively coupled to the plasma source through a resonant electric circuit, the radio-frequency generator being adapted to receive direct current power from a direct current power supply and for generating radio-frequency power at a frequency f, the radio-frequency power including a reactive radio-frequency power oscillating in the resonant electric circuit and an active radio-frequency power absorbed by the plasma. The radio-frequency plasma generating system includes a unit for measuring an efficiency of conversion E of direct-current power to active radio-frequency power absorbed by the plasma and a unit for adjusting the frequency f as a function of the measured efficiency of conversion E to maintain the efficiency of conversion E in a predetermined range within a RF plasma operational range.

Abstract: A motor device for providing propulsion of a floating vessel includes an electrical motor and a propeller arrange inside a propeller house, a hollow rotatable or non-rotatable mid-section arm, a battery and controlling unit. A controlling logic for motor control is arranged inside the rotatable or non-rotatable mid-section arm. The controlling logic includes a heat conductive substrate arranged to contact the inner surface of the rotatable or non-rotatable mid-section arm in a portion of the inner circumference of the rotatable or non-rotatable mid-section arm.

Abstract: Motor assembly for providing propulsion of a floating vessel, comprising: motor device (23), mounting means (24, 32) for attaching the motor device (23) to the floating vessel, the motor device (23) comprising an electrical motor (4) and a propeller (5) arrange inside a propeller house (3).