A detection system for identifying deterioration in a structure is provided that has acoustic sensors that receive acoustic emission waves. The acoustic emission wave detected by the acoustic sensor is identified as a hit. An analysis circuit is present that identifies an A state, a B state, and a C state. The B state has increased hit activity from the A state where a rate B is greater than a rate A by a factor of f1. The C state has increased hit activity from the B state where a rate C is greater than the rate A by a factor of f2. An alarm is activated when an amount of time that the C state is identified as being present reaches a value of TM, or alternatively when a threshold value based upon of the number of hits and time in the C state is reached.

A detection system for identifying deterioration in a structure is provided that has acoustic sensors that receive acoustic emission waves. The acoustic emission wave detected by the acoustic sensor is identified as a hit. An analysis circuit is present that identifies an A state, a B state, and a C state. The B state has increased hit activity from the A state where a rate B is greater than a rate A by a factor of f1. The C state has increased hit activity from the B state where a rate C is greater than the rate A by a factor of f2. An alarm is activated when an amount of time that the C state is identified as being present reaches a value of TM, or alternatively when a threshold value based upon of the number of hits and time in the C state is reached.

A superficial foreign bodies detecting system for ultrasonic sensor is disclosed. The system comprises a micro controller which comprises a main controlling unit, a driving signal generating unit, a signal receiving unit, and a residual vibration detecting unit. The driving signal generating unit is controlled by the main controlling unit so as to transmit a first sensor driving signal to the ultrasonic sensor, thereby making the sensing head to output an ultrasonic wave. In case of the transmission of the first sensor driving signal is stopped, the residual vibration detecting unit is enabled to apply a residual vibration measuring process to the ultrasonic sensor. Consequently, according to a residual vibration signal received from the residual vibration detecting unit, the main controlling unit is able to judge whether there is at least one foreign body attached on the surface of the sensing head.

A system is described for time synchronizing digitized measurement signals, such as vibration signals. The digitized signals, which are acquired asynchronously by multiple distributed measurement units, indicate the operational condition of a machine or a process. To measure the phase of the digitized signals relative to a pulse tachometer input, the time between the leading edge of the tachometer pulse and the digitized samples is measured. To achieve phase-coherent synchronization across the distributed measurement units, a local synchronization signal is embedded into the data produced by the measurement units. The systems uses the synchronization signal to align the data in post processing, which phase aligns the data and aligns the data in absolute time. The synchronization signal may be encoded with a timestamp to provide additional timing information.

This disclosure provides some implementations of systems, methods and apparatus associated with a drive scheme for ultrasonic transducer pixel readout. In some implementations, a piezoelectric ultrasonic transducer has a first electrode, a second electrode, and a piezoelectric layer disposed between the first and second electrodes. The second electrode is coupled with a sampling node. A sampling diode has an input and an output. The input is coupled to receive a diode bias signal. The output is coupled with the sampling node. Controller circuitry is configured to control the diode bias signal to at least partially drive a voltage at the sampling node. Read circuitry is coupled with the sampling node to read the voltage.

A bolt sensor assembly provides a body adapted for insertion into a hole in a component, the body having a first end and a second end, and a longitudinal axis extending therebetween. The first end includes an attachment means for attachment of the bolt sensor assembly to the component, and the second end mounts a sensor element, such as a strain gauge element. The sensor element is movable with respect to the body in the direction of the longitudinal axis of the body and the sensor element is constrained against rotation about the longitudinal axis with respect to the body.

A bolt sensor assembly provides a body adapted for insertion into a hole in a component, the body having a first end and a second end, and a longitudinal axis extending therebetween. The first end includes an attachment means for attachment of the bolt sensor assembly to the component, and the second end mounts a sensor element, such as a strain gauge element. The sensor element is movable with respect to the body in the direction of the longitudinal axis of the body and the sensor element is constrained against rotation about the longitudinal axis with respect to the body.

A device, system and method for monitoring a cable for a physical disturbance is disclosed. The device includes at least one pair of acoustic transducers, the pair comprising a first acoustic conductor monitoring transducer and a second ambient transducer. The acoustic conductor monitoring transducer is in acoustic contact with an acoustic conductor to be monitored by the device, with the transducers being arranged such that an ambient acoustic signal is common to both transducers. The device further includes a circuit element, with each transducer being connected to an input of the circuit element, the circuit element being arranged to output a difference between the input signals from the transducers. An alarm triggering module is connected to an output of the circuit element, the module being operable to trigger an alarm when the output signal received from the circuit element exceeds a predefined threshold value.

A device, system and method for monitoring a cable for a physical disturbance is disclosed. The device includes at least one pair of acoustic transducers, the pair comprising a first acoustic conductor monitoring transducer and a second ambient transducer. The acoustic conductor monitoring transducer is in acoustic contact with an acoustic conductor to be monitored by the device, with the transducers being arranged such that an ambient acoustic signal is common to both transducers. The device further includes a circuit element, with each transducer being connected to an input of the circuit element, the circuit element being arranged to output a difference between the input signals from the transducers. An alarm triggering module is connected to an output of the circuit element, the module being operable to trigger an alarm when the output signal received from the circuit element exceeds a predefined threshold value.

A monitoring device and a method for detecting mechanical torsional oscillations in a rotor shaft of a turbine-generator system. Specifically, the monitoring device and a method for detecting mechanical torsional oscillations in a turbine-generator system having a plurality of, such as two, three, four, five, six or more, turbines that are interconnected by means of a common turbine shaft.