An adaptive inspection carriage for inspecting the rails of a railroad by one or more detectors supported by the carriage. The carriage includes a frame having a generally rectangular configuration with oppositely disposed side members and transverse members. The side members may be in an operative position extending parallel to a respective rail to be inspected. The transverse members may be in an operative position extending in a direction transverse to the rails. Each transverse member may be connected at one end with a side member by means of a swivel coupling having one swivel axis perpendicular to the plane of the generally rectangular frame and another swivel axis parallel to the side member, and connected at the other end to another side member by a swivel coupling having one swivel axis perpendicular to the plane of the rectangular frame and no swivel axis parallel to the second side member.

An apparatus and method for rail inspection include a inspection carriage that moves atop a rail and carries a rail height sensor directed toward the rail. The rail height sensor generates a signal correlated with a vertical position (height) of the rail relative to the carriage as the carriage moves along the rail. A signal processor converts the rail height signal to a log of rail heights along the rail. Further processing of the log, e.g., in the signal processor, identifies crushed head defects in the rail.

A method for estimating a variation in a preload applied to a linear guideway of a machine tool includes steps of: a) obtaining, via each of vibration sensors, first and second vibration signals that are generated according to detection of vibration of a table disposed on the linear guideway respectively at first and second time instants; b) determining, via the computation module, first and second natural frequencies based on a theoretical mode shape and respectively on the first and second vibration signals; and c) determining, via the computation module, the variation in the preload based on the first and second natural frequencies.

A method and system for inspecting a rail by guided waves, the rail being instrumented by sensors. The method comprises the steps of receiving elastic wave measurements from one or more sensors, as a train passes, releasing energy as guided waves into the rail; and of determining a function representative of the impulse response of the rail and the sensors. Developments describe how to determine the existence, position and characterisation of a defect in the rail (e.g. fracture, incipient fracture, etc.), the use of inter-correlation analyses, correlation of the coda of correlations, Passive Inverse Filter, imaging techniques. Other aspects are described for exploring rail defects: sensor position and movement, acquisition time, sampling frequency, frequency filters, amplifications, techniques for learning during successive train passes, signal injection by transducers. Software aspects are described.

A method and system for inspecting a rail profile include using ultrasonic phased arrays. Determined anomalies, such as material flaws like volumetric defects and cracks, in a fluid-immersed rail profile are detected by employing one or more phased array probes located proximate the rail profile. Electronic delays and beam steering and focusing can be employed to tailor the inspection to the rail geometry.

An ultrasonic inspection apparatus for an ultrasonic inspection system for inspecting a railway track, the ultrasonic inspection system for attaching to a bogie for pulling over the railway track, comprising a framework for attaching to the bogie, a sled for inspecting a rail, the sled carrying an array of ultrasonic transducers for detecting flaws in the rail, the system further comprising a water subsystem for ensuring fluid coupling between the sled and the rail, automatic lateral position rectification subsystem for keeping the sleds centered over the railway tracks as the train moves along the track, the ultrasonic transducers in data communication with a computing system in a wagon over the bogie for analyzing and mapping the flaws in the rail, wherein at least one pair of ultrasonic transducers is mounted in the same housing thereby shortening the length of the sled to be irrigated.

A method detects the presence of a vehicle on a railway track using a sensing processor monitoring a sensing system for detecting vibration into ground installed along the railway track. The sensing system includes a detection module for detecting a vehicle on the railway track. The method includes an initialization step which includes the sub-steps of emitting a first signal to be received by the sensing processor through the sensing system, sending a first message to the sensing processor, monitoring the sensing system, and configuring the detection module in function of the received first signal and configuration data received in the first message. The configuration data can include location of the initialization device, intensity/magnitude of the first signal, emission time of the first signal, and/or type of object corresponding to the first signal.

Methods and apparatus, including computer program products, are provided for nonlinear ultrasonic testing. In one aspect there is provided a method, which may include generating at least one ultrasonic wave to enable the at least one ultrasonic wave to propagate through a solid; detecting the at least one ultrasonic wave propagating through the solid; and determining a stress of the solid based on at least one of an imaginary component of a wavenumber, a wave amplitude, a wave strength, a statistical moment in a time domain, or a statistical moment in a frequency domain of the at least one ultrasonic wave.

A railway inspection system for monitoring defects of a rail, including an inspection vehicle configured for traversing the rail, a sensor disposed on the vehicle configured for obtaining rail condition data, a memory disposed on the vehicle and storing previous rail condition data from a previous traversal of the rail, a display device disposed on the vehicle, a processor disposed on the vehicle and a non-transitory computer-readable medium disposed on the vehicle and containing instructions, which when executed by the processor, cause performance of the following steps in real-time as the vehicle traverses the rail, namely obtaining current rail condition data from the sensor, displaying on the display device representative images of the current rail condition data, retrieving the previous rail condition data from the memory, and displaying on the display device representative images of the previous rail condition data.

In some example implementations, there is provided a method. The method may include generating, by an air-coupled transducer, a first ultrasonic guided wave to cause the generated ultrasonic guided wave to propagate into a rail being tested for one or more defects, wherein a frequency of the first ultrasonic guided wave is controlled by at least changing the frequency of a voltage sent to the air-coupled transducer generating the first ultrasonic guided wave; receiving, by a receiver, a second ultrasonic guided wave, wherein the second ultrasonic guided wave is received from the rail; and analyzing a signal representative of the received second ultrasonic guided wave to detect the one or more defects in the rail. Related systems, methods, and articles of manufacture are also provided.