Abstract: A method of controlling an actuator includes transmitting a drive signal to an actuator motor to move a device, including automatically compensating for and rejecting uncertain and unmodeled torque disturbances of the actuator motor. A controller for an actuator includes a processing device configured to transmit a drive signal to an actuator motor to move a device, including automatically compensating for and rejecting uncertain and unmodeled torque disturbances of the actuator motor to perform the method.

Abstract: An optical sensor includes an optic fiber optically coupled to a cavity. An optical path is defined from the fiber, across the cavity, and reflected back across the cavity back into the fiber. The cavity is an open cavity that is in fluid communication with an environment ambient to the cavity for detection of changes in index of refraction inside the cavity due to whether the environment ambient to the cavity is gaseous or liquid.

Abstract: A thermo-optic coefficient measurement system can include a housing structure configured to retain at least a first plate sample, a second plate sample, and a third plate sample in a stacked, alternating stagger arrangement such that a gap exists between the first plate sample and the third plate sample that is the thickness of the second plate sample. The system can also include a first optical device connected to the housing to output a first laser configured to be coincident with the first plate sample and the third plate sample. The first optical device can be configured to receive a first return signal. The system can also include a second optical device connected to the housing to output a second laser configured to be coincident with the second plate sample, the second optical device can be configured to receive a second return signal.

Abstract: A Fabry-Pérot sensor assembly includes an optical element defining a Fabry-Pérot optical cavity therein. A sensor ferrule is affixed to the optical element. The sensor ferrule is configured to physically connect to an optical fiber, optically aligning and spacing the optical fiber with the optical cavity. The sensor ferrule defines a bore for receiving the optical fiber. The bore extends along a longitudinal axis that extends to the optical element. The optical cavity is a second optical member defined between a first optical member and a third optical member spaced apart from the first optical member along the longitudinal axis. The first optical member includes a curved lens surface facing away from the optical cavity and into the bore, configured to collimate light passing through the first optical member.

Abstract: A liquid level sensing system includes a sensing probe including an axial guided wave (AGW) transducer, the AGW transducer including a sensing element, and a rod operatively associated with the AGW transducer, the AGW transducer operatively connected to a first end of the rod. The liquid level sensing systems includes a liquid tank, such that a second end of the rod extends through an opening in an inner wall of the liquid tank into the liquid tank, the first end of the rod and the AGW transducer being outside of the inner wall of the liquid-hydrogen tank.

Abstract: A Fabry-Pérot sensor assembly includes an optical element defining a Fabry-Pérot optical cavity therein. A sensor ferrule is affixed to the optical element. The sensor ferrule is configured to physically connect to an optical fiber, aligning the optical fiber optically with the cavity. The optical element includes a LaGd doped hafnium or zirconium oxide ceramic or Nd:YAG ceramic or single crystals.

Abstract: A Fabry-Pérot sensor assembly includes an optical element defining a Fabry-Pérot optical cavity therein. A sensor ferrule is affixed to the optical element. The sensor ferrule is configured to physically connect to an optical fiber, optically aligning and spacing the optical fiber with the optical cavity. The sensor ferrule defines a bore for receiving the optical fiber. The bore extends along a longitudinal axis that extends to the optical element. The optical cavity is a second optical member defined between a first optical member and a third optical member spaced apart from the first optical member along the longitudinal axis. At least one of the first optical member and the third optical member includes a radiused surface bounding the optical cavity and spanning across the optical cavity laterally relative to the longitudinal axis.

Abstract: A method includes receiving wavelength domain data for a time step, performing a Discrete Fourier Transform (DFT) to transform the wavelength domain data for the time step into frequency domain data for the time step only for the limited set of frequency bins associated with a frequency of interest, calculating pressure based on the frequency domain data for the time step, and updating the frequency of interest and the limited set of frequency bins. The method includes repeating receiving wavelength data for subsequent time steps, performing a DFT to transform the wavelength data for the respective subsequent time steps, calculating pressure for each subsequent time step, and updating the frequency of interest and limited set of frequency bins for each subsequent time step. The method includes outputting pressure data based on calculating pressure for the subsequent time steps.

Abstract: A laser diode drive system configured to output a drive signal to control a voltage provided to a laser diode can include a circuit sensor system configured to output a sensed signal indicative of a drive current of a laser diode, and a temperature sensor configured to output a temperature signal indicative of a temperature of the laser diode or an ambient temperature of the laser diode. The system can include a temperature compensation system configured to output a correction signal based on the temperature signal to compensate for a temperature dependent factor in the sensed signal.

Abstract: In accordance with at least one aspect of this disclosure, a sensing system includes a sensor mat configured to conform to a component having a central axis, a first sensor cluster disposed on or in the sensor mat configured to sense one or more conditions at a first location on the component, and a second sensor cluster disposed on or in the sensor mat configured to sense one or more conditions at a second location circumferentially spaced to the first location. In embodiments, the second location can be diametrically opposed to the first location.

Abstract: A system includes an illuminator. A first end of an optic fiber is operatively connected to the illuminator for transmitting illumination along the length of the optic fiber. An optical sensor operatively connected to the second end for reflecting sensor returns of the illumination back along the length of the optic fiber. A set of fiber Bragg grating (FBGs) is formed in the optic fiber between the first end and the optical sensor. A delay span is included in the optic fiber between the FBGs and the optical sensor. An interrogator is operatively connected to the first end to receive the sensor returns and the FBG returns from the optic fiber. The delay span has a length along the fiber that is configured to create a delay between when the interrogator receives the FBG returns and when the interrogator receives the sensor return.

Abstract: A resistance measurement system includes a plurality of resistors connected in series along a single line. The plurality of resistors includes N resistors. The system includes a plurality of capacitors for at least N?1 of the resistors. Each capacitor is connected in parallel to the single line with a respective resistor to form a respective resistor-capacitor (RC) pair. Each RC pair includes a different time constant such that each RC pair reaches a steady state voltage at a different time. The system includes a current supply connected to the single line to supply a current to the line. The system includes a control module configured to sense a total voltage across the single line and to successively determine resistance of each resistor from the total voltage based on the current, a known total steady state voltage, and known time-to-steady-state-voltages of each RC pair and/or resistors.

Abstract: A smart sensor can include a plurality of analog-to-digital converters (ADCs) configured to receive analog signals from a sensor module, and a plurality of channel modules. Each channel module can be connected to a respective ADC and each channel module can include a limited data processing module configured to provide initial processing. The sensor can include a data control module operatively connected to each of the plurality of channel modules and configured to select a selected channel of the plurality of channels to receive initially processed data from the limited data processing module of the selected channel. The data control module can be configured to interface with external memory to store data to the external memory and/or to read data from the external memory.

Abstract: A smart sensor can include a plurality of analog-to-digital converters (ADCs) configured to receive analog signals from a sensor module, and a plurality of channel modules. Each channel module can be connected to a respective ADC and each channel module can include a limited data processing module configured to provide initial processing. The sensor can include a data control module operatively connected to each of the plurality of channel modules and configured to select a selected channel of the plurality of channels to receive initially processed data from the limited data processing module of the selected channel. The data control module can be configured to interface with external memory to store data to the external memory and/or to read data from the external memory.

Abstract: A heatsink system includes a heatsink plate having a first set of slots defined in a first face thereof and a second set of slots defined in a second face thereof opposite the first face. The first and second sets of slots are configured to house phase change material (PCM) therein.

Abstract: A sensor system can include a sensor configured to output raw sensor data, a plurality of processing modules configured to process the raw sensor data from the sensor to output processed sensor data, a state module for each processing module operative to cause a respective processing module to receive and/or process the sensor data, and a control module configured to receive a coded bitstring and activate or deactivate a predefined set of state modules based on the coded bitstring to control which processing modules process the sensor data and/or an order of processing. The coded bitstring can include a plurality of discrete bits less than the amount of processing modules and/or state modules. A plurality of the state modules and/or processing modules can be associated with at least one discrete bit of the plurality of discrete bits such that each coded bitstring corresponds to a predetermined group of state modules and/or processing modules.

Abstract: In accordance with at least one aspect of this disclosure, a dongle for a sensor system can include a pass-through signal carrier configured to allow signals from a sensor discretely associated with the dongle to pass through the dongle to a data concentrator via a first connection, and a non-volatile memory configured to connect to the data concentrator via a second connection. The nonvolatile memory can include calibration data for the sensor that is associated with the dongle.

Abstract: A Fabry-Pérot sensor assembly includes an optical element defining a Fabry-Pérot optical cavity therein. A ferrule is affixed to the optical element. The ferrule is configured to physically connect to an optic fiber, aligning the optic fiber optically with the cavity. The optical element includes a MgAl2O4 spinel or aluminum oxynitride Al23N27O5. A method of making an Fabry-Pérot optical cavity includes using a ceramic processing etching process to remove material from a first optical member to form the cavity therein, leaving a rim of the optical member surrounding the cavity peripherally. The method includes affixing a second optical member to the rim to enclose the cavity.

Abstract: A method of controlling an actuator includes transmitting a drive signal to an actuator motor to move a device, including automatically compensating for and rejecting uncertain and unmodeled torque disturbances of the actuator motor. A controller for an actuator includes a processing device configured to transmit a drive signal to an actuator motor to move a device, including automatically compensating for and rejecting uncertain and unmodeled torque disturbances of the actuator motor to perform the method.

Abstract: In accordance with at least one aspect of this disclosure, a lens is provided. The lens can be used in an imaging platform of a moving platform (e.g., a projectile or guided munition), for example, in a seeker arrangement. The lens can be configured to optical rotation information of the moving platform to an optical sensor as the moving platform moves in space, for example, following a mission profile.