Determination of the vibrating phase by a time-averaged shadow moire method.

Area of Science:

• Optics and Photonics
• Mechanical Engineering
• Vibration Analysis

Background:

• Traditional time-averaged shadow moire methods primarily capture the amplitude distribution of object vibrations.
• Determining the phase distribution of vibrations using these methods is challenging.

Purpose of the Study:

• To present a modified time-averaged shadow moire method for determining the vibration phase at any point on an object.
• To enable comprehensive vibration analysis beyond amplitude.

Main Methods:

• The reference grating's illumination angle is periodically oscillated at the same frequency as the object's vibration.
• This synchronized oscillation causes stationary contour fringes to shift into vibrating regions.
• The phase of the illumination angle oscillator is used as a reference signal to determine the vibration phase.

Main Results:

• The modified method successfully determines the vibration phase of arbitrary positions on a vibrating object.
• Stationary contour fringes are observed to shift in response to in-phase oscillations of the illumination angle.
• The vibration phase can be accurately measured by analyzing the signal phase added to the illumination angle oscillator.

Conclusions:

• The proposed time-averaged shadow moire technique effectively measures vibration phase, complementing amplitude information.
• This advancement offers a more complete understanding of object dynamics under vibration.
• The method provides a valuable tool for vibration analysis in various engineering applications.