Provided is an exciter device for fatigue testing of a blade of a wind turbine, including a actuator for generating a periodic excitation force and a coupling device for coupling the actuator to a blade to be tested. The exciter device includes a pretensioning device applying a pretension such that the excitation force only acts in a pulling or pushing direction over the whole period.

The present invention relates to a full-field vibration measurement method based on microwave sensing, which is characterized by comprising the following steps: step 1, repeatedly transmitting linear frequency modulated continuous wave microwave signals by means of one or more transmitting antennas; step 2, receiving reflected signals from targets and/or measurement points by means of a plurality of receiving antennas, and performing frequency mixing on received signals and local oscillator signals to obtain multi-channel intermediate frequency baseband signals; step 3, acquiring intermediate frequency baseband signals in various channels, and resolving and positioning targets and/or measurement points within the full field based on a joint range and angle dimension; and step 4, extracting vibration displacement time-domain information of targets to be measured and/or measurement points. By means of the full-field vibration measurement method based on microwave sensing provided in the present invention, synchronous vibration information measurement of targets and/or measurement points within the full field is achieved by positioning and resolving the targets and/or measurement points within the full field based on a joint range-angle dimension and tracking phase evolution, thereby solving the difficulties in the prior art that full-field vibration measurement and interference suppression cannot be achieved.

An example test system includes a tray to hold devices, where the devices include devices to be tested or devices that have been tested; a motor that is controllable to cause vibrations; and a component that couples the motor to the tray to cause the tray to vibrate in response to the vibrations of the motor.

A data compression process reduces the amount of machine spectral data transmitted over a network while maintaining the details of spectral peaks used for machine health analysis. The data compression process also provides for the calculation of various types of spectral parameters, such as spectral band parameters, with negligible loss of accuracy.

An anomaly detecting device includes: a singular value decomposition unit configured to perform singular value decomposition of a variance-covariance matrix of a measured value matrix y.sub.0 composed of measured values acquired by a plurality of sensors in a time period considered to be normal, to thereby calculate a singular vector U and a singular value matrix S; an anomaly determination unit configured to apply the singular vector U and the singular value matrix S to a measured value matrix y.sub.t to be evaluated and which is acquired in an arbitrary time period to determine whether an anomaly is present from a result of application; and an anomalous part identification unit configured to, when the measured value matrix y.sub.t is determined to be anomalous, identify an anomalous part based on a diagonal element of a matrix obtained in association with the measured value matrix y.sub.t.

Systems and methods are provided for evaluating a device design to reduce audio speaker generated vibrational energy transfer between adjoining components of a device. The method performs a system-level modal analysis on the design to extract a natural frequency and a mode shape and thereafter create an analysis monitoring point on the design between two adjacent components defining a relative distance. Simulation inputs are fed into a linear dynamics finite element analysis (FEA) solver to solve system equations for a relative displacement of the two adjacent components at the analysis monitoring point, and if the solved relative displacement causes the relative distance to be equal to or less than a zero-relative distance value, then the device design is modified by at least one value of an element from one of the two adjacent components.

A device for real-time monitoring and early warning a bridge based on foldable triboelectric nanogenerators, comprising a signal generator, a data acquisition and transmission module, and a data processing and early warning module sequentially connected. The signal generator comprises an internal unit and an external unit, and the external unit comprises a lower sleeve, a device sidewall and a lower magnet; the lower magnet is fixed at the bottom of the lower sleeve; the internal unit comprises a cover plate, an upper magnet, an upper sleeve and a flexible multilayer triboelectric nanogenerators; the flexible multilayer triboelectric nanogenerators is inserted into the gap between the lower sleeve and the device sidewall; the cover plate is located at the upper end of the flexible multilayer triboelectric nanogenerators; the upper sleeve is inserted into the lower sleeve; and the upper magnet is fixedly provided at the bottom of the upper sleeve.

Provided is an additive manufacturing system capable of performing in-process, layer-by-layer non-destructive testing, the additive manufacturing system including: a plate for producing a part thereon; a transducer attached to the plate and configured to induce vibrations in the part; and a laser vibrometer configured to detect a vibrational response of the part to determine whether defect and/or anisotropy exists within the part.

A vibration control device, while applying Gaussian vibration that matches a target vibration physical quantity PSD to a test piece, makes a corresponding vibration physical quantity non-Gaussian. Using a response vibration physical quantity PSD and a target vibration physical quantity PSD, a control vibration physical quantity PSD calculation generates a control vibration physical quantity PSD for generating a drive signal. A PSD conversion converts the control vibration physical quantity PSD into a control corresponding vibration physical quantity PSD of another dimension. Using the control corresponding vibration physical quantity PSD, a control corresponding vibration physical quantity waveform calculation calculates a control corresponding vibration physical quantity waveform that is non-Gaussian. At least based on the control characteristics and the control corresponding vibration physical quantity waveform, a drive waveform calculation generates a next drive waveform such that vibration that matches the control corresponding vibration physical quantity waveform is applied to a test piece.

An elastic material vibration test apparatus includes a lower support plate having an upper surface on which an elastic material to be tested is placed, an upper support plate disposed above the lower support plate to be spaced apart from the lower support plate, a pillar connecting the lower support plate and the upper support plate, a pressing rod configured to pass through the upper support plate and ascend and descend in a vertical direction, an air bearing installed on the upper support plate and supporting an outer surface of the pressing rod in a non-contact state, a pressing plate coupled to a lower end of the pressing rod to press an upper surface of the elastic material, and one or more weights coupled to the pressing rod above the air bearing.