in this paper, concept of cross-bispectrum is used to investigate and model vibration interaction due to nonlinearities in faulted drive shafts in an AH-64 helicopter. Most of the currently available vibration-monitoring tools are built around autoand cross-power spectral analyses which have limited value in detecting frequency correlations higher than first order. Studying higher order correla...

The bearings are the most important mechanical elements of rotating machinery. They are employed to support and rotate the shafts in rotating machinery. On the other hand, any fault in bearing can lead to losses on the level of production and equipments as well as creation an unsafe working environment for human. For these reasons, Condition monitoring and fault diagnosis of these bearings has ...

The task of measuring rotating shafts angular deformation by means ultrasonic vibration meter is considered in the article. Measurement parameters objects an urgent technical diagnostics electromechanical units, turbines, drilling rigs and metal-cutting machines subject to disturbances. measured include their torques arising from torsional vibrations shafting stationary mobile objects. Timely m...

Dynamic behavior of a circular shaft with geometrical nonlinearity and constant spin, subjected to periodic axial load is investigated. The case of parametric combination resonance is studied. Extension of shaft center line is the source of nonlinearity. The shaft has gyroscopic effect and rotary inertia but shear deformation is neglected. The equations of motion are derived by extended Hamilto...

Based on a capacitive angle and angular rate sensor, a sensor measuring the relative angle between two rotating shafts has been developed. Two rotatable electrodes are placed between two sensor plates. The relative angle between the two rotors and the absolute position of the rotor blades are calculated from measurements of the capacitive coupling between different transmitting stator segments ...

This paper provides a broad review of the state of the art in Lissajous curve techniques, with particular regard to rotating machinery. Lissajous figure is a subject too wide-ranging to allow a comprehensive coverage of all of the areas associated with this field to be undertaken, and it is not the authors' intention to do so. However, a general overview of the broader issues of Lissajous curve...