Apparatuses, systems, and methods that provide a delayed output signal with reduced sampling error are described. Embodiments include a clock circuit that generates a sample clock signal having a predetermined sample clock period. A sampling circuit may generate samples of a received signal during each sample clock period. An interpolation circuit may estimate a value of the received signal at times between the samples of the received signal based on at least a first sample and a second sample of the received signal. The interpolation circuit may estimate a time that the received signal crosses a threshold, and determine a time delta between the first sample and the estimated time that the received signal crosses the threshold. A delay circuit to generate a time delay substantially equal to the time delta is also included. An output signal changes state after the generated time delay.

An abnormality determining device includes: a current value detecting unit configured to detect a current value which is a value of a drive current of a motor; a variance ratio calculating unit configured to group time-series current values detected in time series by the current value detecting unit at a predetermined time interval, to calculate a variance value of the current values of each group, and to calculate a variance ratio of each group by dividing the variance value of the current values of the corresponding group by a variance value of a reference current value of the motor when a reduction gear is normal; and a determination unit configured to determine that the reduction gear is abnormal when the variance ratios calculated by the variance ratio calculating unit for all the groups are equal to or greater than a threshold value.

An abnormality determining device includes: a current value detecting unit configured to detect a current value which is a value of a drive current of a motor; a variance ratio calculating unit configured to group time-series current values detected in time series by the current value detecting unit at a predetermined time interval, to calculate a variance value of the current values of each group, and to calculate a variance ratio of each group by dividing the variance value of the current values of the corresponding group by a variance value of a reference current value of the motor when a reduction gear is normal; and a determination unit configured to determine that the reduction gear is abnormal when the variance ratios calculated by the variance ratio calculating unit for all the groups are equal to or greater than a threshold value.

A propulsion system is described that includes an electrical bus, a generator configured to provide electrical power to the electrical bus, a plurality of propulsory configured to provide thrust by simultaneously being driven by the electrical power at the electrical bus, and a controller. The controller is configured to synchronize a rotational speed of an individual propulsor from the plurality of propulsory with a rotational speed of the generator after the individual propulsor has become unsynchronized with the rotational speed of the generator by controlling at least one of the rotational speed of the generator, nozzle area of the individual propulsor, or a pitch angle of the individual propulsor.

A system for monitoring the health of one or more bearings of a journal assembly is provided. The system includes a split spacer, one or more vibration sensors, a speed sensor, and a controller. The split spacer is configured to be disposed on a shaft of the journal assembly, the shaft is configured to support the bearings. The vibration sensors are configured to detect vibrations emitted by the bearings. The speed sensor is configured to measure the rotational speed of the bearings. The controller is configured to electronically communicate with the vibration sensors and the speed sensor and calculate a health status of the bearings. The split spacer includes two portions that define a cavity configured to abut the shaft so as to allow the vibration sensors to be disposed inside the split spacer and next to the one or more bearings.

A system for monitoring the health of one or more bearings of a journal assembly is provided. The system includes a split spacer, one or more vibration sensors, a speed sensor, and a controller. The split spacer is configured to be disposed on a shaft of the journal assembly, the shaft is configured to support the bearings. The vibration sensors are configured to detect vibrations emitted by the bearings. The speed sensor is configured to measure the rotational speed of the bearings. The controller is configured to electronically communicate with the vibration sensors and the speed sensor and calculate a health status of the bearings. The split spacer includes two portions that define a cavity configured to abut the shaft so as to allow the vibration sensors to be disposed inside the split spacer and next to the one or more bearings.

Embodiments relate to a position sensor comprising a magnetic target. The magnetic target includes a magnetic multipole configured to generate a magnetic field. The magnetic field has three mutually-perpendicular components at a first region. Sensor elements can be configured to measure these field components at the first region. In embodiments, comparing the amplitudes of the components can be used to determine a global position, and the instantaneous values of these components can be used to determine a local position.

A speed sensor for detecting a speed of a magnetizable object. The speed sensor (100) can be supplied with an electric alternating signal with a first frequency by an electric signal source. The speed sensor including: a primary coil for generating a magnetic alternating field with the first frequency; first and second secondary coils. The first and second secondary coils can each be magnetically coupled to the primary coil via a magnetizable object. First and second electric signals induced in the first and second secondary coils respectively by the generated magnetic alternating field; a Goertzel filter bank detects first and second amplitude values of respective spectral components of the induced first and second electric signals in the event of a second frequency which differs from the first frequency. A processor determines the speed of the magnetizable object depending on the detected first amplitude value and the detected second amplitude value.

An angular velocity sensor includes an angular velocity sensor element, a drive circuit, a detection circuit, and a reference potential supply circuit. The angular velocity sensor element has a monitor electrode, a drive electrode, a sense electrode, and a weight. The reference potential supply circuit supplies a reference potential to the angular velocity sensor element. The reference potential supply circuit has a first CV converter, a second CV converter, a comparator, and a reference potential adjustment circuit. The first CV converter is connected to the monitor electrode. The second CV converter is connected to the sense electrode. The comparator compares a frequency of a signal being output from the first CV converter with a frequency of a signal being output from the second CV converter, and outputs a signal depending on a result of the comparison.

A method for calibrating a radial acceleration sensor of a wheel of a vehicle including the following steps: acquisition, by the sensor, of signals S.sub.i, each signal S.sub.i being acquired during a predetermined time window W.sub.i when the vehicle is in motion, the windows W.sub.i being different from one another; detection, for each time window W.sub.i, of local extrema of the signal S.sub.i associated respectively with phase values and detection instants; determination, for each time window W.sub.i, of a frequency F.sub.i of the rotation of the wheel of the vehicle as a function of the phase values and of the detection instants for the local extrema detected; low-pass filtering of the signals S.sub.i, so as to obtain, for each time window W.sub.i, a filtered value Z.sub.i; calibration of a constant error E.sub.c of the radial acceleration sensor as a function of the filtered values Z.sub.i and of the frequencies F.sub.i.