There is disclosed a device for use in evaluating the integrity of soil behind a wall of an infrastructure. The device generally has a frame having a plurality of rests adapted to be received onto the wall during use; a hammer assembly having an actuator fixedly mounted to the frame and a hammer element having a head movably mounted to the frame, the actuator being actuatable to move the head to strike the wall while the plurality of rests hold the frame in a fixed position relative to the wall; and a sensor configured and adapted to sense vibrations of a portion of the wall resulting from the strike and to generate a vibration signal indicative thereof.

A new vibration test-cell that allows a static load to be applied simultaneously with lateral vibration coupled with in-situ microscopy that allows for the ability to open a fatigue crack up to a desired gap, as well as generate acoustic emission (AE) from vibration excitation, micro-fracture events are captured by the AE measurement while the physical observation of the crack faying surfaces is performed in-situ with an optical microscope embedded in the test cell.

A vibration test jig may include an upper jig frame to which a vibration test object is fixed and a lower base frame mounted to an oscillator, and a plurality of double parallelograms connected between the jig frame and the base frame, for generating displacements in an upward/downward direction and/or a forward/rearward direction. Each of the double parallelograms may include a complex four-articulation link structure and a wire rope isolator. The vibration test jig can simulate a deformation mode due to generation of resonances.

Deriving a clean timing signal from a waveform is disclosed. A sensor-of-interest (SOI) sample set and a waveform sample set that correspond to the SOI sample set in time is collected. The waveform sample set is partitioned into a plurality of waveform sample subsets, and the SOI sample set is partitioned into a plurality of SOI sample subsets, each SOI sample subset corresponding to one of the plurality of waveform sample subsets. A plurality of waveform sample subset angular speeds is determined, wherein each waveform sample subset angular speed corresponds to a different waveform sample subset. An aggregate mean angular speed based on the plurality of waveform sample subset angular speeds is determined. Each SOI sample subset is resampled to the aggregate mean angular speed based on the corresponding waveform sample subset angular speed to generate a plurality of resampled SOI subsets.

Systems and methods for conformal imaging vibrometry capable of real-time measurements of the dynamic motions of any arbitrary two-dimensional or three-dimensional structure. The systems and methods are able to fully characterize the dynamic behavior of an object of any arbitrary geometry. The test object is illuminated with multiple laser beams whose directions conform to the local normal axis of the surface. The approach enables high-speed vibration imaging of whole-body dynamics of arbitrarily shaped structures in real-time, with no multiplexed data capture or synthesized motion reconstruction, as is currently practiced. By measuring the object's vibrations simultaneously at multiple points, the disclosed systems and methods are able to reproduce the structural behavior under operational conditions, which can then be spectrally decomposed to determine the modal, complex modal and transient nature of the true structural dynamics.

A vehicle inspection apparatus includes: an exciter roller (3) configured to apply vibration to a vehicle (6); a control device 5 configured to control the exciter roller (3); and a vibration setting unit (the control device (5)) configured to set a vibration that is input to a wheel (7) of the vehicle (6) when abnormal noise generated in the vehicle (6) is detected. The control device (5) provides a range of vibrations including the vibration set by the vibration setting unit and applies the range of vibrations to the vehicle (6).

An optimization analysis method for joining locations of an automotive body obtains optimal locations of additional joining points or joining portions for use in joining parts assemblies together in an automotive body model and includes: a step of obtaining a deformation form in a vibration mode occurring in the automotive body model 31 by frequency response analysis; a step of determining a load condition to be given to the automotive body model in correspondence with the deformation form in the obtained vibration mode; a step of generating an optimization analysis model in which additional joining candidates are set at locations to be candidates for joining parts assemblies together; a step of setting an optimization analysis condition; and a step of giving the determined load condition to the optimization analysis model to perform optimization analysis and obtaining the additional joining candidates satisfying the optimization analysis condition as optimized joining points.

A rotating system comprising two or more blades 3 mounted on a hub installed on a rotatable propeller shaft 1, each blade provided with a respective sensor 4 arranged to detect response of the respective blade to harmonic excitation; and the system further comprising means configured to compare the response of the respective blade to that of the other blade(s).

A sensor system provides measurement of building interstory drift based on a laser beam impinging on a discrete diode sensor array. The diode sensor array determines the location at which a projected laser bean strikes the array, which provides a direct measurement of interstory drift. The diode sensor array is a two dimensional array of discrete diodes that allow the location of an impinging laser beam to be very accurately tracked as the beam moves back-and-forth across the diode array. Local rotations of the laser source that result from rotations of structural members (e.g. floor beam rotation) are appropriately corrected for. This allows accurate, dynamic measurements of the interstory drift between two floor levels of a shaking building.

An observation system includes an information acquiring section configured to acquire sensor information from a sensor section set in a structure and configured to detect vibration of the structure and a processing section configured to calculate information concerning a peak vibration frequency of the vibration on the basis of the sensor information and determine a surface state of the structure on the basis of the information concerning the peak vibration frequency.