Phase Demodulation in Angular Vibration Measurements
نویسنده
چکیده
The paper deals with the problem of angular vibration measurements in time history of rotation angle, angular velocity or angular acceleration. The source of information about angular vibrations is an encoder producing an impulse signal. It is supposed that the impulse frequency is changed proportionally to the rotational frequency. A time record of an impulse signal is transformed to an analytical signal using Hilbert transformation. The unwrapped phase of the analytical signal gives the rotation angle, which is employed to evaluation of angular velocity and angular acceleration.
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