Estimation of material characteristics using video imaging technology

This presentation describes the use of video imaging to estimate material properties of a structure within a region of interest. The first technology examined is video magnification, which is a technique that magnifies motions that are mathematically present in a video but often not visible to the human eye. The second technology examined is digital image correlation, which uses two angled cameras to track and quantify all components of the three-dimensional vibration field that are present in the plane of the video. Several recent papers have shown that video imaging may be used to derive quantitative information about vibration without contacting the structure. In the present work, a mechanical excitation is applied to the center of a region of interest on a structure. The excitation is concentrated in space and time. The response of the structure is captured at high temporal and spatial resolution by a video camera focused on the area of interest. Material properties are then estimated by adjusting values in a model of the region until agreement is obtained throughout the temporal and spatial responses in the video. The present work allows one to understand physical mechanisms and improve numerical models. Results will be presented.This presentation describes the use of video imaging to estimate material properties of a structure within a region of interest. The first technology examined is video magnification, which is a technique that magnifies motions that are mathematically present in a video but often not visible to the human eye. The second technology examined is digital image correlation, which uses two angled cameras to track and quantify all components of the three-dimensional vibration field that are present in the plane of the video. Several recent papers have shown that video imaging may be used to derive quantitative information about vibration without contacting the structure. In the present work, a mechanical excitation is applied to the center of a region of interest on a structure. The excitation is concentrated in space and time. The response of the structure is captured at high temporal and spatial resolution by a video camera focused on the area of interest. Material properties are then estimated by adjusting val...