Embodiments herein provide a system (100) to estimate the amplitude of oscillations in a turbulent flow system (102) that exhibits oscillatory instabilities. The system (100) comprises of a sensor (102A) mounted on the turbulent flow system (102) to detect an oscillatory variable in the system obtaining a signal, a signal conditioner (104) that conditions the signal from the sensor, an amplitude estimator (110) that estimates the amplitude of the limit cycle oscillations, and also predict the proximity of the system to the oscillatory instability, a processor (108) connected to the amplitude estimator (110) to compare the predicted oscillation amplitude with a threshold value. The amplitude is estimated by estimating the spectral measure of the time series signal obtained from the system.

A system and method of monitoring a tubular structure is provided. The method includes: a) sensing one or more parameters relating to the tubular structure at spaced apart positions along the length of the tubular structure using a sensor module array having a plurality of sensor modules disposed in a cable attached to the tubular structure, the plurality of sensor modules producing communication signals representative of the sensed parameter at each position along the length of the tubular structure; and b) using a control unit to communicate with the sensor modules in the array, including receiving communication signals representative of the sensed parameter at each position along the length of the tubular structure, and processing the communications signals to produce information relating to the sensed parameter at the positions along the length of the tubular structure.

Provided is a hammering test system. A hammering test system includes a hammering test device including a target, a traveling mechanism for automatically traveling on a to-be-tested surface, a marking mechanism configured to perform marking on the to-be-tested surface, an adsorbing mechanism for adsorbing to the to-be-tested surface, and a hammering test mechanism configured to conduct a hammering test on the to-be-tested surface, and a surveying instrument capable of performing automatic tracking and distance and angle measurements of the target. A hammering test is conducted by causing the hammering test device to travel to a desired position while adsorbing to a to-be-tested surface by the adsorbing mechanism. When it is determined that there is an abnormality, a marking is marked on the to-be-tested surface. The surveying instrument automatically tracks the target, and when conducting a hammering test, makes distance and angle measurements of the target.

A hammering test system includes a hammering test device including a target, a flying unit, and a hammering test mechanism configured to conduct a hammering test on a test object, a surveying instrument including a scanner for acquiring point cloud data by scanning with scanning light, and configured to be capable of performing tracking and distance and angle measurements of the target, and an arithmetic processing unit including a point cloud data analyzing unit configured to calculate shape data by analyzing point cloud data acquired by the scanner, and a flight plan calculating unit configured to calculate a flight plan of the hammering test device based on the shape data calculated by the point cloud data analyzing unit, and the surveying instrument tracks the target of the hammering test device and makes distance and angle measurements when the hammering test mechanism conducts a hammering test.

A method and system for identifying a cavity position of a structure based on global search includes: step 1: using a structure requiring cavity position identification as a target area, arranging acoustic emission sensors at key positions of the target area, and acquiring actual travel time of signals between the acoustic emission sensors on site; step 2: constructing cavity models for the target area; and for each cavity model, tracking shortest paths of signal propagation between the acoustic emission sensors when each cavity model exists in the target area, to obtain theoretical travel time of the signals; and step 3: respectively calculating deviations between the theoretical travel time and the actual travel time of the signals between the acoustic emission sensors corresponding to each cavity model, and using a position of a cavity model corresponding to a minimum deviation as an identified cavity position in the target area.

The invention relates to a portable device for measuring vertical rail measurements under service to record and report excessive vertical rail movement to prevent a train from derailing. The device may be pivoting with a tilt sensor and light-weight. The device may include a microprocessor, sensors, and a display. The device may be installed on the rail. The device may sense an approaching train, automatically turn on the device, and measure the real-time vertical displacement and the maximum/minimum vertical movement of the rail while the train is operating over the rail at all speeds.

A method to assess the integrity of a structure is provided and comprises the steps of: i) applying a sinusoidally varying force to the structure at a frequency or frequencies below the lowest frequency that could cause resonance in the structure whereby to set up a dynamic response dominated by the stiffness of the structure; and ii) monitoring the dynamic response of the structure. A device to assess the integrity of a structure is also provided.

A structural health monitoring system comprises a first set of sensors operable for coupling to a structure positioned under ground, the first set of sensors further configured to detect an impact upon the structure while the first set of sensors is positioned under the ground; a second set of sensors operable to be positioned on or proximate to a surface of the ground, the second set of sensors further configured to detect an audible event occurring at a distance from the second set of sensors and the structure; and a computer readable memory storing one or more audio signatures that may correspond to the audible event.

A state estimation apparatus 1 includes an acquisition unit 2 that acquires deterioration information indicating a deterioration state of each structural object and a learning unit 3 that learns common information that is common between pieces of the deterioration information and estimation index information that is used for estimating a deterioration state of a target structural object, using the deterioration information as input.

A method of retrieving a mobile platform from a tank at least partially filled with a non-conductive, energetic substance includes configuring the mobile platform to include at least a retrieval system including a buoyant body, an electrically conductive member, and a tether. The tether electrically isolates the buoyant body from the enclosure. The method further includes the steps of releasing the buoyant body to convey the tether toward a surface of the non-conductive, liquid energetic substance; conveying an electrically conductive cable to the electrically conductive member using the tether; electrically connecting a voltage neutralizing end of the electrically conductive cable to a voltage differential neutralizing body in a spark inhibiting ambient condition; electrically connecting a mobile platform end of the electrically conductive cable to the electrically conductive member of the mobile platform while the electrically conductive member is below the surface of the non-conductive, liquid energetic substance.