Abstract: An example apparatus includes a controller configured to control operation of a salient-type, multiphase motor in accordance with a technique including periodic on and off-times, the motor including a stator and a rotor. The controller is configured to calculate or receive values representing changes in current to the motor during the respective on and off-times or measurements proportional thereto, and calculate an inductance of the motor as a function of the values and a supply voltage to the motor. And the controller is configured to determine a position of the rotor based on the inductance of the motor, and control operation of the motor based on the position of the rotor.

Abstract: An actuation system having a configuration of first and second components, each component having longitudinally extending fingers interlaced with one another. Relative longitudinal movement is permitted between the fingers in a manner to permit the second component to be movable longitudinally with respect to the first component between a first position and a second position. A biasing member is provided within the configuration that biases the second component towards the second position. A wire is wound about the fingers that restrains the second component in the first position. A release device selectively causes the wire to be loosened about the fingers such that the biasing member moves the second component from the first position to the second position. An actuator connected to the second component moves with the second component from the first position to the second position.

Abstract: A multi-stage drive includes a linear actuator configured for linear movement along an actuation axis, and a control surface. The control surface is operatively connected to the linear actuator for rotation about a deployment axis in a deployment stage, and for rotation in a control stage about a control axis that is different from the deployment axis, so that movement of the linear actuator along the actuation axis drives rotation of the control surface in both the deployment stage and in the control stage.

Abstract: A method for evaluating a collective alignment of rotor blades for an aircraft while the aircraft is on the ground is disclosed. The method includes determining an air density altitude, and determining a torque value for each engine of the aircraft, while the aircraft rotor blades are operated at a normal speed and the rotor blades are set to a full down position for ground operations via a collective controller. The method further includes evaluating the collective condition by comparing the torque value to a predetermined flat pitch torque alignment limit for the air density altitude, and providing an indication of the collective condition.

Abstract: A system and method is provided for monitoring aircraft health and status using a situation-aware sensing system. The system includes an independent power source, a sensor that continuously measures a signal of interest to yield sensor data, and a processor that compares the sensor data to threshold data. The processor adjusts an operational parameter of the situation-aware sensing system to conserve power when the sensor data does not exceed the threshold data. The processor further adjusts the operational parameter of the situation-aware sensing system to stop conserving power when the sensor data exceeds the threshold data.

Abstract: Disclosed is a rotor track and balance system for rotorcraft that includes a data processing unit, a tachometer sensor and at least one accelerometer. The tachometer sensor is located remotely from the data processing unit and is mounted proximate to the rotating blades of the rotorcraft. The tachometer sensor is adapted to measure the speed and position of the rotating blades and to wirelessly transmit speed and position data to the data processor. The at least one accelerometer is also located remotely from the data processing unit and is mounted proximate the rotating blades of the rotorcraft. Each accelerometer is adapted to measure vibration anomalies in the rotating blades and to wirelessly transmit vibration data to the data processor. The data processing unit synchronizes the wireless data transmitted from the tachometer sensor and the wireless accelerometer(s) and determines necessary adjustments to be made in order to reduce the vibration anomalies in the rotor blades.

Abstract: Disclosed are systems and methods for retaining and deploying a plurality of canards and canard covers on a projectile. The projectile includes a projectile housing defining an interior chamber and a longitudinal axis, canards rotatably mounted to the housing, canard covers, a bobbin movably disposed in the interior chamber of the housing along the longitudinal axis, and rocker arms. The canards mounted for movement from a stowed position to a deployed position. The canard covers have a hook element and are adapted to cover respective slots formed in the housing. The bobbin has first and second ends and a retaining surface proximate the second end. Rocker arms have a first and second arm end, with a canard retaining slot defined therebetween. The first arm end includes a latch element for engaging with the canard cover element, and the second arm end is positioned proximate the retaining surface.

Abstract: A sensor system for providing control of an electric motor having an inductive angle sensor system including a first inductive coil configured for affixation to a rotor shaft of the electric motor wherein rotation of the rotor shaft causes corresponding rotation of the first inductive coil. A second inductive coil fixedly mounted in spaced relationship to the first inductive coil. An evaluation circuit coupled to the second inductive coil and to the electric motor operative to determine a rotor shaft angle for the rotor shaft of the electric motor through evaluation of an induced magnetic field between the first and second inductive coils.

Abstract: An aircraft sensor system including a primary module configured to be attached to an aircraft portion and operative to transmit electrical power wirelessly. A secondary module configured to be attached to an aircraft component, the secondary module operative to receive electrical power wirelessly from the primary module. At least one sensor configured to be operatively attached to a portion of the aircraft component and electrically coupled to the secondary module, wherein the at least one sensor is operative to measure a desired parameter of the aircraft component.

Abstract: A reflector target includes a reflector defining a tapered reflector surface. The reflector includes an apex opening and an opposed base opening, wherein the base opening has a larger perimeter than the apex opening. The tapered reflector surface extends between the openings forming a tapered passage there-between. The tapered reflector surface is configured to resist the accumulation of surface bubbles on the reflector surface by movement of bubbles along the reflector surface out through the apex opening.

Abstract: Synchronizing at least one wireless sensor includes sending at least one reference message along with a request for acquired data from an access point to the at least one wireless sensor, where the reference message includes a first timestamp indicating when the reference message was sent according to time of a clock of the access point, receiving from the at least one wireless sensor a response that includes the requested data, the first timestamp, and at least one other timestamp corresponding to time of a clock of the at least one wireless sensor, and determining a relative clock offset of the at least one wireless sensor using the timestamps.

Abstract: Synchronizing a wireless sensor includes receiving a first command at the wireless sensor, noting a first timestamp value indicating when the first reply is sent, responding to the first command with a first reply, receiving a second command at the wireless sensor that contains a second timestamp value indicating when the first reply was received and a third timestamp value indicating when the second command was sent to the wireless sensor, noting a fourth timestamp value indicating when the second command was received by the wireless sensor, and determining an offset at the wireless sensor using the first, second, third, and fourth timestamp values. The presence of the first timestamp value may be interpreted as a request to provide timestamp information for synchronization. An access point may communicate with the wireless sensor.

Abstract: Described are techniques for selecting options used with current sensor data characterizing vibration caused by rotating blades. Sets of other sensor data are evaluated to determine a first of the sets of other sensor data that is a best match for said current sensor data. Each of the sets of other sensor data is associated with one of a plurality of option sets. Each option set includes options used in determining one or more adjustments that may be applied to the blades to reduce vibration. The one or more sets of other sensor data are evaluated to determine a first of the sets of other sensor data that is a best match for said current sensor data. A first of the plurality of option sets associated with said first set of sensor data is used in determining adjustment(s) that may be applied to the blades.

Abstract: An actuation system having a configuration of first and second components, each component having longitudinally extending fingers interlaced with one another. Relative longitudinal movement is permitted between the fingers in a manner to permit the second component to be movable longitudinally with respect to the first component between a first position and a second position. A biasing member is provided within the configuration that biases the second component towards the second position. A wire is wound about the fingers that restrains the second component in the first position. A release device selectively causes the wire to be loosened about the fingers such that the biasing member moves the second component from the first position to the second position. An actuator connected to the second component moves with the second component from the first position to the second position.

Abstract: A fin retention and deployment mechanism includes a detent in each of a plurality of fins, a mechanism that engages the detent, and at least one spring clip that maintains each of the fins in a non-deployed position. The mechanism also includes a gas generator, a manifold, coupled to the gas generator and having a plurality of cylinders in fluid communication with gas from the gas generator, and a plurality of pistons disposed in the cylinders. A bottom of each of the pistons is coupled to each of the fins to provide deployment thereof when a corresponding top of each of the pistons is acted upon by gas from the gas generator. In response to the gas generator expelling gas, the pistons may move the fins to a deployed position.

Abstract: A method for evaluating a collective alignment of rotor blades for an aircraft while the aircraft is on the ground is disclosed. The method includes determining an air density altitude, and determining a torque value for each engine of the aircraft, while the aircraft rotor blades are operated at a normal speed and the rotor blades are set to a full down position for ground operations via a collective controller. The method further includes evaluating the collective condition by comparing the torque value to a predetermined flat pitch torque alignment limit for the air density altitude, and providing an indication of the collective condition.

Abstract: A system for reducing reactive components in ullage of a fuel tank, typically the fuel tank of an airplane. The system includes an air driven unit for creating a fluidic motive force to remove ullage from the fuel tank, and a main catalytic unit for receiving the ullage and reducing the reactive components to yield processed ullage for return to the fuel tank.

Abstract: A bearing system for a spin-stabilized projectile including bearing configurations that permit selective relative rotation between a spindle and a body portion and which facilitate automatic centering of the spindle. Each bearing configuration includes a conical bearing surface rotatable with respect to a corresponding conical body surface. One bearing configuration is in a forward portion of the body portion and selectively engages a first body surface upon the projectile experiencing set-back forces to direct forces away from bearing elements, and another bearing configuration is in a rearward portion of the body portion and engages a second body surface upon the projectile experiencing set-forward forces to direct forces away from the bearing elements.

Abstract: An example method includes receiving output voltage data from an array of at least four thermopiles placed around the circumference of a projectile such that for any rotation of the projectile during flight thereof, at least a pair of the thermopile having upwardly-facing fields of view referenced to the earth-fixed coordinate system. The method includes determining the pair of upwardly-facing thermopiles based on the output voltage data from the array, with the respective pair of thermopiles including a thermopile p and next adjacent thermopile p+1. The method includes determining a ratio of the output voltage data from thermopiles p and p+1, and applying the ratio to a function associating, for any pair of thermopiles n and n+1, a ratio of output voltage data from thermopiles n and n+1, and a roll angle ?n of thermopile n referenced to the earth-fixed coordinate system.

Abstract: An apparatus for synchronizing devices includes a central access point node configured to utilize a low latency protocol to transmit a series of synchronization messages to the devices, transmit and receive data acquisition commands and responses from the devices using a high reliability protocol different from the low latency protocol, and calculate and apply relative clock offsets for each device based on the series of synchronization messages. The apparatus may also account for failure in delivery of a portion of the series of synchronization messages by recording timestamp data at the devices to send to the central access point prior to the central access point calculating the relative clock offsets.