Disclosed is a method for estimating the tension of a tension member (1), the method comprising the steps of exciting the tension member (1) such as to induce vibration of the tension member (1), sampling the vibration to obtain a first vibration signal (VS1), modifying the mass and/or the rotational inertia of the tension member (1) such as to provide a modified tension member (1a), exciting the modified tension member (1a) such as to induce vibration of the modified tension member (1a), sampling the vibration of the modified tension member to obtain a second vibration signal (VS2), and estimating the tension of the tension member based on a comparison of the first vibration signal (VS1) and the second vibration signal (VS2). Disclosed is also a system for estimating the tension of a tension member.

Disclosed is a method for estimating the tension of a tension member (1), the method comprising the steps of exciting the tension member (1) such as to induce vibration of the tension member (1), sampling the vibration to obtain a first vibration signal (VS1), modifying the mass and/or the rotational inertia of the tension member (1) such as to provide a modified tension member (1a), exciting the modified tension member (1a) such as to induce vibration of the modified tension member (1a), sampling the vibration of the modified tension member to obtain a second vibration signal (VS2), and estimating the tension of the tension member based on a comparison of the first vibration signal (VS1) and the second vibration signal (VS2). Disclosed is also a system for estimating the tension of a tension member.

A rotor for a turbomachine includes a disc and a plurality of blades fixed to the disc. Each blade of the plurality of blades is fixed to the disc via a lattice structure configured so that a tensile force applied to the lattice structure induces a change in the angle of incidence of the blade. The blades and the lattice structures are configured so that: (i) when the rotor is stationary, the distribution of the angles of incidence of the blades around the disc is aperiodic, and (ii) when the rotor is rotating at a predetermined rotational speed, the angles of incidence of the blades are identical.

A damage diagnosis device is provided with: a detection unit for detecting that, immediately after a vehicle crossing a bridge has exited from the bridge, another vehicle is not crossing the bridge; a determination unit for determining whether the weight of the vehicle satisfies a criterion; and a diagnosis unit that, when the detection unit has detected that no other vehicle is crossing the bridge and the determination unit has determined that the weight of the vehicle satisfies the criterion, diagnoses damage to the bridge on the basis of information representing free vibration generated in the bridge due to the crossing of the vehicle, thereby improving the precision of diagnosis when damage to a bridge is diagnosed on the basis of information representing free vibration generated in the bridge due to the crossing of a vehicle.

A monitoring device includes a process data acquisition unit configured to acquire process data indicating an operation condition of a machine having a rotating shaft, a shaft vibration value acquisition unit configured to acquire a measurement value of a shaft vibration value of the rotating shaft under the operation condition indicated by the process data, a determination model configured to determine a normal value of the shaft vibration value according to the operation condition created on the basis of the shaft vibration value measured during an operation of the machine and the shaft vibration value calculated on the basis of a predetermined shaft vibration calculation model, and a monitoring unit configured to evaluate the measurement value of the shaft vibration value on the basis of the process data, the measurement value of the shaft vibration value, and the determination model.

A self-adjusting static pressured plane guide rail consists of a base, slider provided on the base and an upper pressing plate corresponding to the shoulders on both sides of the slider; wherein: each upper pressing plate's outer edge contacts the base to form a fulcrum and the upper pressing plate's inner edge acts as the force portion and a upper pressing block is set between force portion and the slider's shoulder and a metal wire is set between the upper pressing block's top surface and the force portion's bottom surface of upper pressing plate along the slider's sliding direction; the upper pressing plate is provided with pre-tightening bolt to connect the base in a fixed way. When vibration frequency changes during operation, the oil film gap changes accordingly due to pre-tightening bolt's elasticity of the mutual function and the metal wire's elasticity to always maintain oil film layer's rigidity function.

A self-adjusting static pressured plane guide rail consists of a base, slider provided on the base and an upper pressing plate corresponding to the shoulders on both sides of the slider; wherein: each upper pressing plate's outer edge contacts the base to form a fulcrum and the upper pressing plate's inner edge acts as the force portion and a upper pressing block is set between force portion and the slider's shoulder and a metal wire is set between the upper pressing block's top surface and the force portion's bottom surface of upper pressing plate along the slider's sliding direction; the upper pressing plate is provided with pre-tightening bolt to connect the base in a fixed way. When vibration frequency changes during operation, the oil film gap changes accordingly due to pre-tightening bolt's elasticity of the mutual function and the metal wire's elasticity to always maintain oil film layer's rigidity function.

A technique facilitates the use and application of a distributed vibration sensing system in, for example, a well application. The technique enables selection of a desired gauge length to achieve an optimum trade-off between the spatial resolution of a distributed vibration sensing/distributed acoustic sensing system and signal-to-noise ratio. The optimum gauge length can vary according to specific factors, e.g. depth within a well, and the present technique can be used to account for such factors in selecting an optimal gauge length which facilitates accurate collection of data on dynamic strain.

A fixture for testing stiffness of a vehicle wheel by measuring vibration of the wheel includes a base and a retention member. The retention member is integral to the base. The retention member defines a distal end including a distal diameter and a proximal end being proximate to the base and including a proximal diameter. The proximal end includes a plurality of studs extending upwardly therefrom for being received by lug apertures defined by the vehicle wheel thereby securing the vehicle wheel to the retention member. The distal diameter includes a ratio to the proximal diameter of between 0.6 to 0.8 to one.

System and methods for characterizing a response of a structure-under-test to applied excitation forces using a test fixture. The fixture is selectively coupleable to the structure-under-test and is configured to hold the structure-under-test at a known position and in a known orientation relative to the fixture. A plurality of excitation devices and response sensors are coupled to the fixture. Excitation forces applied to the fixture by the excitation devices are conveyed by the fixture to the structure-under-test and each response sensor measures a dynamic response indicative of a response of the structure-under-test and the fixture to the applied excitation force. A controller receives response sensor data and applies a mathematical coordinate transformation to project the forces and moments corresponding to the applied excitation and the measured dynamic responses to a target point of the structure-under-test and to calculate a system response function based at least in part on the projection.