The present invention relates to resin compositions, fiber reinforced polymeric structures and electromagnetic induction processes for making same. Such magnetic induction processes are pulsed processes that can be optionally coupled with cooling steps between pulses. The aforementioned fiber reinforced polymeric structures can take forms that include, but are not limited to, pipes; pressure vessels, including rocket motor cases and fire extinguishers; golf club shafts; tennis and badminton racquets; skis; snowboards; hockey sticks; fishing rods; bicycle frames; boat masts; oars; paddles; baseball bats; and softball bats. In addition, such fiber reinforced polymeric structures can be supplemented with other materials, such as a rocket propellant, to form articles, for example, a rocket motor.

A rocket engine comprises a combustion chamber and a rocket nozzle that communicates with the combustion chamber. A metal wire supply device supplies a metal wire, which is fuel, to the combustion chamber. A water vapor generator supplies water vapor as an oxidant to the combustion chamber. An ignition device ignites the metal wire in a water vapor atmosphere.

A rocket engine comprises a combustion chamber and a rocket nozzle that communicates with the combustion chamber. A metal wire supply device supplies a metal wire, which is fuel, to the combustion chamber. A water vapor generator supplies water vapor as an oxidant to the combustion chamber. An ignition device ignites the metal wire in a water vapor atmosphere.

A modulation device for modulating a gas ejection section, the device being for placing in a nozzle upstream from the throat of the nozzle, the modulation device including a plug having a downstream end forming a member for partially obstructing the nozzle throat; and a plug guide having an internal housing in which the upstream end of the plug is present. The upstream end of the plug is suitable for sliding in the internal housing of the plug guide between a first position in which the upstream end of the plug is present in an upstream portion of the internal housing, and a second position in which the upstream end is present in a downstream portion of the internal housing. The upstream end of the plug is held in the first position by at least one retaining element for breaking under the effect of heat.

A solid propellant propulsion motor may comprise: a forward propellant grain extending along a longitudinal axis of a motor case between a forward end of the motor case and a first burn inhibitor layer in the motor case; the first burn inhibitor layer disposed axially adjacent to the forward propellant grain; an aft propellant grain disposed axially adjacent to the first burn inhibitor layer; a second burn inhibitor layer disposed axially adjacent to an aft end of the aft propellant grain; and an ablative material layer disposed on a radially inner surface of the aft propellant grain.

A fuel grain for a hybrid rocket engine includes multiple, concentric cylindrical layers of fuel grain material defining a combustion port extending axially through the fuel grain, in which each layer includes multiple beads of fuel grain material, in which the multiple beads in a given layer are disposed adjacent to one another and bonded together, and in which adjacent concentric layers are bonded together. Each bead of fuel grain material includes a polymer based rocket fuel material and a nanoscale metallic material, and a composition of the beads of the fuel grain material varies along a radius of the cylindrical fuel grain.

A fuel grain for a hybrid rocket engine includes multiple, concentric cylindrical layers of fuel grain material defining a combustion port extending axially through the fuel grain, in which each layer includes multiple beads of fuel grain material, in which the multiple beads in a given layer are disposed adjacent to one another and bonded together, and in which adjacent concentric layers are bonded together. Each bead of fuel grain material includes a polymer based rocket fuel material and a nanoscale metallic material, and a composition of the beads of the fuel grain material varies along a radius of the cylindrical fuel grain.

A method of making a fuel grain for a hybrid rocket engine includes deposing beads of fuel grain material onto mandrel using additive manufacturing to form a cylindrical fuel grain, each bead including a polymer based rocket fuel material and a nanoscale metallic material. The deposing includes deposing multiple, adjacent beads to form concentric layers of beads, wherein a composition of the beads of the fuel grain material differs between the beads of a first layer and the beads of a second layer of the fuel grain.

A propulsion system for use with a satellite comprises a substrate, a communication network and a cluster of individually selectable solid fuel motors mounted on the substrate and operatively connected to the communication network. A controller is also operatively connected to the communication network and operative to select any one of more motors of the cluster of individually selectable solid fuel motors and transmit signals to fire the one or more motors of the individually selectable solid fuel motors. The substrate may have various configurations. The cluster of motors may comprise 10-1000 motors, which may be arranged in a rectangular array or other formation. Subsets of motors having different impulse capabilities may be employed. In this manner, lighter, smaller, flexible and more efficient propulsions systems may be provided for use in attitude control, etc. of satellites.

A propulsion system for use with a satellite comprises a substrate, a communication network and a cluster of individually selectable solid fuel motors mounted on the substrate and operatively connected to the communication network. A controller is also operatively connected to the communication network and operative to select any one of more motors of the cluster of individually selectable solid fuel motors and transmit signals to fire the one or more motors of the individually selectable solid fuel motors. The substrate may have various configurations. The cluster of motors may comprise 10-1000 motors, which may be arranged in a rectangular array or other formation. Subsets of motors having different impulse capabilities may be employed. In this manner, lighter, smaller, flexible and more efficient propulsions systems may be provided for use in attitude control, etc. of satellites.