Abstract: A rope drive anchoring assembly includes a pulley, a rope, and a rope connector. The pulley is adapted to be rotationally mounted and has an inner surface, an outer surface, and a fastener opening extending between the inner and outer surfaces. The rope engages at least a portion of the outer surface of the pulley and is adapted to receive a drive torque, which causes the pulley to rotate. The rope connector couples the rope to the pulley, and includes a fastener, a threaded bolt, and a spring. The fastener extends through the fastener opening, and has a first end, a second end, an outer surface, and an opening through which the rope extends. The threaded bolt is threaded onto the fastener threads, and the spring is disposed between the threaded bolt and the inner surface of the pulley.

Abstract: A hot-gas thruster is actuated using a relatively small electric motor. The hot-gas thruster includes a pressure assisted pilot shaft to keep electric power demand to only a few hundred watts peak and only tens of watts on average, while exhibiting relatively fast response times.

Abstract: An apparatus and method is provided for operating an aircraft control stick in an active mode and a passive mode. The method comprises subjecting the control stick to an a resilient restoring force in the passive mode, and neutralizing the restoring force in the active mode. A spring assembly is provided for exerting and neutralizing the restoring force, which may be varied between minimum and maximum values.

Abstract: Systems and methods of controlling solid propellant gas pressure and vehicle thrust are provided. Propellant gas pressure and a vehicle inertial characteristic are sensed. Propellant gas pressure commands and vehicle thrust commands are generated. A propellant gas pressure error is determined based on the propellant gas pressure commands and the sensed propellant gas pressure, and vehicle thrust error is determined based on the vehicle thrust commands and the sensed vehicle inertial characteristic. Reaction control valves are moved between closed and full-open positions based on the determined propellant gas pressure error and on the determined vehicle thrust error. The system and method allow the reaction control valves to operate at variable frequencies or at fixed frequencies. The system and method also allows propellant pressure to be commanded to follow a predetermined pressure profile or commanded to vary “on-the-fly.

Abstract: A gas control valve is configured to controllably supply propellant gas to a thruster so that the thruster may produce thrust over a relatively wide range, and so that the thruster exhibits relatively fine minimum impulse bit (MIB) performance. The gas control valve includes a pilot stage having a pilot valve, and a main stage having a main valve. The gas control valve responds to control signals supplied to the pilot stage and is configured such that for commands of relatively short duration, only the pilot valve responds. Conversely, for commands of relatively longer duration, the pilot valve and main valve both respond.

Abstract: A hot-gas thruster is actuated using a relatively small electric motor. The hot-gas thruster includes a pressure assisted pilot shaft to keep electric power demand to only a few hundred watts peak and only tens of watts on average, while exhibiting relatively fast response times.

Abstract: An electromechanical actuator is provided for converting rotary action into linear action, and includes an electric motor, a cable yoke, an output shaft, and a pair of cables. The electric motor is adapted to be selectively energized and is configured, upon being energized to generate a drive torque. The cable yoke is coupled to receive the drive torque and is configured, upon receipt thereof, to rotate about a rotational axis. The output shaft is coupled to receive a drive force and is configured, upon receipt thereof, to translate along a linear axis that is disposed at least substantially perpendicular to the rotational axis. Each cable is wound, in pretension, on a portion of the cable yoke and around a portion of the output shaft. The pair of cables is configured, upon rotation of the cable yoke, to supply the drive force to the output shaft.

Abstract: A gas thruster is configured to supply thrust over a relatively wide range, from a relatively low value to a relatively high thrust value, and exhibits relatively fine minimum impulse bit (MIB) performance. The gas thruster includes a thrust nozzle, a main stage, a main valve element, and a pilot valve. The gas thruster responds to thruster control signals supplied to the pilot valve and is configured such that for commands of relatively short duration, only the pilot valve responds and relatively low thrust is produced. Conversely, for command or relatively longer duration, the pilot valve and main valve element both respond and relatively higher thrust is produced.

Abstract: Systems and methods are provided for regenerative motor braking. The regenerative braking systems and methods allow the braking torque of a multi-phase motor to be controlled while keeping currents to acceptable levels and without supplying electrical energy back to the voltage source. The regenerative braking systems and methods dissipate energy in the motor windings instead of sending this energy to the voltage source by intelligently switching the low-side switches in the inverter between the ON and OFF states at the commutation frequency while maintaining the high-side switches in the inverter in the OFF state.

Abstract: A thrust reverser actuation system includes a plurality of actuators, a power drive unit, and a gear set. Each actuator is coupled to receive an actuator input torque and is configured, upon receipt of the actuator input torque, to move between a stowed position and a deployed position. The power drive unit has only one output shaft, and is configured to supply a drive torque via the output shaft. The gear set is connected to the output shaft and is coupled to each of the actuators. The gear set is configured to receive the drive torque via the output shaft and to supply the actuator input torque to each of the actuators.

Abstract: A control valve having an external valve trim adjustor is provided. The control valve comprises a valve shaft comprising a contact member extending in a direction transverse to the valve shaft, a stationary valve cap adapted to receive the valve shaft, an adjustment member coupled to the valve cap, and a stop plate coupled to the contact member and threadedly coupled to the adjustment member, the stop plate positioned at least partially between the adjustment member and the contact member and adapted to position the contact member away from the valve cap in response to manipulation of the adjustment member.

Abstract: An electromechanical actuator is provided for converting rotary action into linear action, and includes an electric motor, a cable yoke, an output shaft, and a pair of cables. The electric motor is adapted to be selectively energized and is configured, upon being energized to generate a drive torque. The cable yoke is coupled to receive the drive torque and is configured, upon receipt thereof, to rotate about a rotational axis. The output shaft is coupled to receive a drive force and is configured, upon receipt thereof, to translate along a linear axis that is disposed at least substantially perpendicular to the rotational axis. Each cable is wound, in pretension, on a portion of the cable yoke and around a portion of the output shaft. The pair of cables is configured, upon rotation of the cable yoke, to supply the drive force to the output shaft.

Abstract: A system and method of implementing servomechanism control without rate feedback is provided. A position feedback signal is filtered using a non-linear lead-lag filter that has a variable frequency response to thereby generate a compensated position feedback signal. A position error signal is generated from a position command signal and a sensed position signal, and the frequency response of the non-linear lead-lag filter is varied in response to the position error signal. A compensated position error signal is generated from the commanded position signal and the compensated position feedback signal. The compensated position error signal is at least selectively filtered using a non-linear integral filter that has a variable gain to thereby at least selectively supply a filtered position error signal. The gain of the non-linear integral filter is varied in response to the compensated position error signal.

Abstract: Systems and methods of controlling solid propellant gas pressure and vehicle thrust are provided. Propellant gas pressure and a vehicle inertial characteristic are sensed. Propellant gas pressure commands and vehicle thrust commands are generated. A propellant gas pressure error is determined based on the propellant gas pressure commands and the sensed propellant gas pressure, and vehicle thrust error is determined based on the vehicle thrust commands and the sensed vehicle inertial characteristic. Reaction control valves are moved between closed and full-open positions based on the determined propellant gas pressure error and on the determined vehicle thrust error. The system and method allow the reaction control valves to operate at variable frequencies or at fixed frequencies. The system and method also allows propellant pressure to be commanded to follow a predetermined pressure profile or commanded to vary “on-the-fly.

Abstract: A gas control valve is configured to controllably supply propellant gas to a thruster so that the thruster may produce thrust over a relatively wide range, and so that the thruster exhibits relatively fine minimum impulse bit (MIB) performance. The gas control valve includes a pilot stage having a pilot valve, and a main stage having a main valve. The gas control valve responds to control signals supplied to the pilot stage and is configured such that for commands of relatively short duration, only the pilot valve responds. Conversely, for commands of relatively longer duration, the pilot valve and main valve both respond.

Abstract: A gas thruster is configured to supply thrust over a relatively wide range, from a relatively low value to a relatively high thrust value, and exhibits relatively fine minimum impulse bit (MIB) performance. The gas thruster includes a thrust nozzle, a main stage, a main valve element, and a pilot valve. The gas thruster responds to thruster control signals supplied to the pilot valve and is configured such that for commands of relatively short duration, only the pilot valve responds and relatively low thrust is produced. Conversely, for command or relatively longer duration, the pilot valve and main valve element both respond and relatively higher thrust is produced.

Abstract: A gas valve apparatus is provided. A primary valve includes a flapper nozzle valve and first and second outputs. A secondary valve includes a housing having first and second inputs coupled to the first and second outputs of the primary valve, first and second seats coupled to the first and second inputs, first and second nozzles coupled to the first and second seats, and a moveable element configured for alternatively sealing the first and second nozzles as the moving element comes into contact with the first and second seats.

Abstract: A system and method of implementing servomechanism control without rate feedback is provided. A position feedback signal is filtered using a non-linear lead-lag filter that has a variable frequency response to thereby generate a compensated position feedback signal. A position error signal is generated from a position command signal and a sensed position signal, and the frequency response of the non-linear lead-lag filter is varied in response to the position error signal. A compensated position error signal is generated from the commanded position signal and the compensated position feedback signal. The compensated position error signal is at least selectively filtered using a non-linear integral filter that has a variable gain to thereby at least selectively supply a filtered position error signal. The gain of the non-linear integral filter is varied in response to the compensated position error signal.

Abstract: A control valve having an external valve trim adjustor is provided. The control valve comprises a valve shaft comprising a contact member extending in a direction transverse to the valve shaft, a stationary valve cap adapted to receive the valve shaft, an adjustment member coupled to the valve cap, and a stop plate coupled to the contact member and threadedly coupled to the adjustment member, the stop plate positioned at least partially between the adjustment member and the contact member and adapted to position the contact member away from the valve cap in response to manipulation of the adjustment member.

Abstract: An apparatus is provided for a shaft coupling device. The shaft coupling device comprises first and second portions adapted to be coupled together, the first and second portions having a cavity when formed, the cavity adapted to receive two shaft ends, at least one interior wall of the cavity having a frustrum-shaped surface, and the two shaft ends each having at least one spherical-shaped surface.