Abstract: A spacecraft system and method includes a platform with a dock and an umbilical payout device. A robot is connected to an umbilical paid out by the umbilical payout device and is repeatedly deployable from the dock. The robot includes one or more imagers, an inertial measurement unit, and a plurality of thrusters. A command module receives image data from the one or more robot imagers and orientation data from the inertial measurement unit. An object recognition module is configured to recognize one or more objects from the received image data. The command module determines the robot's orientation with respect to an object and issues thruster control commands to control movement of the robot based on the robot's orientation. The combination of the space platform and robot on umbilical line can be used for towing another object to different orbital location, inspection including self-inspection of the robot carrying platform and for robotic servicing.

Abstract: A Hall thruster for use with a condensable propellant including a plasma accelerator including an anode for providing plasma discharge, a distributor for distributing the condensable propellant in a liquid or vaporized state, and an electric circuit including a cathode for emitting electrons attracted to the anode and for neutralizing ion flux emitted from the plasma accelerator. A condensable propellant feed system includes a storage vessel for storing the condensable propellant and providing liquid condensable propellant at a controlled pressure. A condensable propellant flow controller includes a pressure reducing device for controlling the flow rate of the liquid condensable propellant. A vaporizer at or above the vaporization temperature of the liquid condensable propellant vaporizes the liquid condensable propellant at a predetermined vaporization rate and flow rate.

Abstract: A spacecraft system and method includes a platform with a dock and an umbilical payout device. A robot is connected to an umbilical paid out by the umbilical payout device and is repeatedly deployable from the dock. The robot includes one or more imagers, an inertial measurement unit, and a plurality of thrusters. A command module receives image data from the one or more robot imagers and orientation data from the inertial measurement unit. An object recognition module is configured to recognize one or more objects from the received image data. The command module determines the robot's orientation with respect to an object and issues thruster control commands to control movement of the robot based on the robot's orientation. The combination of the space platform and robot on umbilical line can be used for towing another object to different orbital location, inspection including self-inspection of the robot carrying platform and for robotic servicing.

Abstract: An iodine fueled plasma generator system includes a plasma generator. At least one storage vessel is configured to store condensed phase iodine therein. A heating device proximate to the storage vessel is configured to create iodine vapor from the condensed phase iodine. A propellant management subsystem is configured to deliver the iodine vapor to the plasma generator. A feedback control subsystem is responsive to one or more of plasma generator discharge current, the pressure of the iodine vapor, and/or the temperature of the iodine vapor configured to regulate the flow rate of the iodine vapor to the plasma generator.

Abstract: An iodine fueled plasma generator system includes a plasma generator. At least one storage vessel is configured to store condensed phase iodine therein. A heating device proximate to the storage vessel is configured to create iodine vapor from the condensed phase iodine. A propellant management subsystem is configured to deliver the iodine vapor to the plasma generator. A feedback control subsystem is responsive to one or more of plasma generator discharge current, the pressure of the iodine vapor, and/or the temperature of the iodine vapor configured to regulate the flow rate of the iodine vapor to the plasma generator.

Abstract: A Hall thruster with a shared magnetic structure including a plurality of plasma accelerators each including an anode and a discharge zone for providing plasma discharge. An electrical circuit having one or more cathodes connected to the plurality of plasma accelerators emits electrons that are attracted to the anode in each of the plasma accelerators. A shared magnetic circuit structure establishes a transverse magnetic field in each of the plurality of plasma accelerators that creates an impedance to the flow of electrons toward the anode in each of the plurality of plasma accelerators and enables ionization of a gas moving through one or more of the plurality of plasma accelerators. The impedance localizes an axial electric field in the plurality of plasma accelerators for accelerating ionized gas through the one or more of the plurality of plasma accelerators to create thrust.