Abstract: A system and method for generating a tachometer signal from a vibration sensor is disclosed in which an approximately idealized band pass filter is used along with a fast Fourier transform (FFT) to create a sufficient analytic signal to derive the tachometer signal for a shaft or other rotating component. In addition, jitter in the generated tachometer signal, or any tachometer signal, can be reduced by using an approximately idealized low pass filter and then transforming the filtered signal using a real FFT. These processes can be performed using a smart vibration sensor, which facilitates improved vibration analysis on rotating equipment where in the past the addition of a tachometer would be prohibitive due to cost, weight, certification requirements, or physical impracticality.
Abstract: Assessing and removing jitter from tachometer signals enhances the performance of condition monitoring systems where accurate tachometer signals are needed. A system as disclosed herein can be designed and configured to have a low order of operations, so as to allow for implementation on low cost microcontrollers, which can be important for bused, distributed monitoring systems in which the tachometer zero crossing data is collected at a tachometer sensor and then broadcast to other remote sensors needing that information for vibration or other advanced analysis. Moreover, for monolithic architecture systems (e.g., a centralized processing and control architecture), the low order of operation and small software code base allows the system to be a simple/low cost addition to existing monitoring systems.
Abstract: A helicopter rotor blade performance system (BPS) allows for accurate determination of blade track height and blade track phase while reducing size, weight, and complexity of the system. The BPS uses sensing technology that is scalable to adapt to a variety of helicopters and is readily and unobtrusively installed. The BPS includes a bused smart system methodology that can directly measure track height, while phase can be estimated using the time synchronous average of the magnitude or range of the return signal from a radar wave. The BPS includes a rotation monitor, radar tracker, and control unit, that allows for a determination of the track errors and consequentially whether a track rebalancing should occur.