Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : December 22, 2018 - December 24, 2018
In recent years, collapse of large structures has occurred because of aging. Displacement measurement is important for maintenance. There are various methods in the vertical and horizontal directions for displacement measurement of distant objects using optical method. However, there are few methods to measure displacement for a camera direction. In this paper, the authors propose and demonstrate a method to generate a fringe pattern along the depth direction using three-beam interferometry in combination with fringe power analysis. In three-beam interferometry, the fringe pattern along the depth direction appears by superimposing each two-beam interference fringe. Therefore, the power distribution of the fringe pattern appears along the depth direction. This method enables us to directly obtain the three-dimensional (3D) shape and displacement using the fringe pattern along the depth direction. Our method intended for wide application with 3D shape measurements and out-of-plane displacement measurements for the inspection and maintenance of large constructions. As the first step of developing a device for 3D shape and displacement measurement, in this paper, simulation and an experiment were used to confirm that depth directional patterns appeared.
