Abstract: A fuel pump system for an aerial refueling system including: a variable displacement motor operable to be driven by a hydraulic fluid pressure; a fuel pump operable to be driven by the variable displacement motor; and a drive system controller (DSC) connected to the variable displacement motor, wherein the DSC is operable to direct an operation of the fuel pump in modes comprising: a flow control mode operable to maintain an output fuel flow rate from the fuel pump to a predetermined maximum inlet pressure at a reception coupling for a receiver aircraft; a fuel pressure control mode operable to regulate the output fuel flow rate to not exceed the predetermined maximum inlet pressure; and a priority mode operable to reduce the output fuel flow rate in response to a decrease in the hydraulic pressure. Also a method of refueling a receiver aircraft.

Abstract: A fuel pump system for an aerial refueling system including: a variable displacement motor operable to be driven by a hydraulic fluid pressure; a fuel pump operable to be driven by the variable displacement motor; and a drive system controller (DSC) connected to the variable displacement motor, wherein the DSC is operable to direct an operation of the fuel pump in modes comprising: a flow control mode operable to maintain an output fuel flow rate from the fuel pump to a predetermined maximum inlet pressure at a reception coupling for a receiver aircraft; a fuel pressure control mode operable to regulate the output fuel flow rate to not exceed the predetermined maximum inlet pressure; and a priority mode operable to reduce the output fuel flow rate in response to a decrease in the hydraulic pressure. Also a method of refueling a receiver aircraft.

Abstract: A fuel pump system for an aerial refueling system including: a variable displacement motor operable to be driven by a hydraulic fluid pressure; a fuel pump operable to be driven by the variable displacement motor; and a drive system controller (DSC) connected to the variable displacement motor, wherein the DSC is operable to direct an operation of the fuel pump in modes comprising: a flow control mode operable to maintain an output fuel flow rate from the fuel pump to a predetermined maximum inlet pressure at a reception coupling for a receiver aircraft; a fuel pressure control mode operable to regulate the output fuel flow rate to not exceed the predetermined maximum inlet pressure; and a priority mode operable to reduce the output fuel flow rate in response to a decrease in the hydraulic pressure. Also a method of refueling a receiver aircraft.

Abstract: An integrated brushless DC motor and controller including a brushless DC motor having a rotating shaft with a 2 pole permanent magnet affixed to the shaft for rotation thereby in a plane orthogonal to the axis of rotation of the shaft. An X-Y Hall Effect Sensor is carried by a controller mounted on a circuit board attached to the motor and the Hall Effect Sensor is positioned proximate the magnet with the Hall Effect Sensor producing the Sine and Cosine components of the magnetic field as the magnet is rotated by the motor shaft. The electronic controller includes software for determining the motor angle and commutation logic from the Sine and Cosine components generated by the Hall Effect Sensor response to the rotating magnetic field.

Abstract: An integrated brushless DC motor and controller including a brushless DC motor having a rotating shaft with a 2 pole permanent magnet affixed to the shaft for rotation thereby in a plane orthogonal to the axis of rotation of the shaft. An X-Y Hall Effect Sensor is carried by a controller mounted on a circuit board attached to the motor and the Hall Effect Sensor is positioned proximate the magnet with the Hall Effect Sensor producing the Sine and Cosine components of the magnetic field as the magnet is rotated by the motor shaft. The electronic controller includes software for determining the motor angle and commutation logic from the Sine and Cosine components generated by the Hall Effect Sensor response to the rotating magnetic field.

Abstract: Aspects of the present invention are directed to systems, methods, and computer-readable media for measuring certain actuator system parameters of an actuator, e.g., an EMA in its working environment. Stiction and backlash are examples of such parameters, and these indicate the impending failure of an actuator system than conventional approaches of measuring the elapsed time of operation. When the measured backlash and/or stiction parameters exhibit a deleterious increase over time, e.g., by exceeding a preset threshold, imminent failure or the need for service/repair of the system is indicated.

Abstract: An improved technique of acceptance testing an actuator system involves measuring system parameters of the actuator system during operation of the actuator system, and storing the measured system parameters in computerized memory as a set of measured system parameters. The technique further involves obtaining a set of predetermined thresholds. Each predetermined threshold corresponds to a particular measured system parameter. The technique further involves electronically indicating whether the actuator system is in acceptable condition based on an electronic comparison of the set of measured system parameters stored in the computerized memory and the set of predetermined thresholds, e.g., providing a warning of a need for service or of imminent failure when one or more of the system parameters exceeds a corresponding threshold.

Abstract: A power line communication system includes a field-programmable gate array (FPGA) having a sine wave approximator driven by a high frequency clock in the FPGA. The sine wave approximator generates a high frequency sine wave-shaped communication signal on command by a processor. The data transmission scheme includes sending a sequence of fixed length and fixed frequency cells wherein each transmitted cell is of one of four phases 0°, 90°, 180° or 270° (FIG. 2) relative to the phase of a preceding transmitted cell with the first transmitted cell designated as a zero-phase reference cell. The data transmissions are synchronized by the voltage zero crossings of the AC power line and each transmission consists of 27 cells evenly distributed over the AC voltage line half cycle. The high frequency sine wave-shaped communication signal is superimposed on the low frequency (60 Hz) AC power line via a transconductance amplifier which draws current from the AC power line via a full-wave bridge rectifier.

Abstract: A lighting system includes a plurality of control modules distributed on the AC power line for remote control of lights within a residential/office building structure. Each control module is hard-wired to an electrical load and is provided with a dimmer and up to four control switches and LEDs for status indication. Each control module has a data decoder, a switch and LED interface, a dimmer driver and processor with memory for independently processing and communicating data signals to the other control modules on the AC power line without the need for a central processor to coordinate the lighting control operation. Every control module is programmable through a programmable module and a PC. The system data downloaded to each control module includes a unique address, a system configuration file and a response file for evaluating system transmission commands. Each control switch may be programmed to control the hard-wired load or any other load in the system.

Abstract: A power line communication circuit comprises a rectifier connected to an a.c. power line utility source. The rectifier draws power from the a.c. power source and produces a low-frequency rectified d.c. voltage signal across its positive and negative output terminals with the negative output terminal being referenced as a circuit ground. The rectified d.c. voltage signal is received by a voltage-to-current converter connected to the positive output terminal of the rectifier. The voltage-to-current converter also receives a high-frequency a.c.-shaped communication input voltage signal from an external high-frequency a.c.-shaped communication signal generator. In response to the two input voltage signals, the voltage-to-current converter generates an output current which contains a low frequency d.c. component from the rectified d.c. input voltage signal and a high frequency a.c.-shaped component from the a.c-shaped high frequency communication input voltage signal. The high frequency a.c.

Abstract: A PWM switching power supply of the buck regulator type converts an unfiltered rectified d.c. input voltage into a regulated stepped down d.c. output voltage for use by load circuits. The power supply includes a PWM switching regulator which controls the duty cycle of an N-channel field effect transistor (FET) power switch which has its source connected to a Schottky flyback diode. The flyback diode is connected to an LC output filter which generates the stepped down output voltage. The PWM regulator includes a 555 timer operating in conjunction with an RC timing network in a modulated a stable mode. Timer 555 has an output lead electrically connected to the gate of the FET for switching the FET on/off in response to an output voltage modulating feedback input from a feedback path with the source of the FET serving as the “ground” for the PWM regulator.

Abstract: A method and system for advancing the state of commutation of an electronically commutated brushless D.C. motor. Impending motor stall is detected by measuring current flow through the motor windings to ascertain magnetic saturation. Upon such detection, a time sequence is started and if a change of state has not occurred within the time sequence, the state is advanced to the next succeeding state.

Abstract: To allow a displacement sensor to operate independently of changes in the excitation signal to the transducer, a demodulating circuit utilizing a single integrator is provided wherein comparison is made between the excitation signal and a reference signal, the comparison is used to adjust an output generating circuit which generates the output from the transducer. Advantageously, the output generating circuit can provide movement information from output of the transducer which include position, velocity and acceleration.

Abstract: To allow a displacement sensor to operate independently of changes in the excitation signal to the transducer, a demodulating circuit is provided wherein comparison is made between the excitation signal and a reference signal, the comparison is used to adjust an output generating circuit which generates the output from the transducer. Advantageously, the output generating circuit can provide movement information from output of the transducer which include position, velocity and acceleration.

Abstract: A hydromechanical differentiating system for actuator dynamic stiffness enhancement and dynamic load damping. A free floating spool valve receives a pressure signal and moves in opposite directions away from a null position. When the valve moves in response to an increase in the pressure signal it compresses fluid in a chamber connected at the opposite end of the cylinder in which the spool moves and simultaneously connects a source of fluid under pressure to the chamber causing the valve to return to its null position. Conversely, if the pressure signal decreases, the spool valve allows the fluid in the chamber to expand moving the valve away from the chamber and simultaneously connecting system return to the chamber to decrease the fluid pressure in the chamber and cause the valve to return to its null position.

Abstract: The back emf voltage of a motor is extracted from the applied motor voltage and motor current by means of a control system including a back emf sensor, an adaptive motor resistance circuit, and a position integrator. In the back emf sensor a corrected motor resistance signal, iR, a motor inductance signal, L di/dt, and applied motor voltage, V.sub.m, are input to a summing junction. The summing junction subtracts the motor resistance signal and the motor inductance signal from the applied motor voltage to compute the back emf voltage. To correct for variations in motor resistance, the adaptive motor resistance circuits demodulates and integrates the back emf voltage from the summing junction and the motor position signal input to the system. By integrating the back emf voltage from the back emf sensor in the position integrator a motor position output is obtained as a signal for servo position loop closure.