Displacement and strain measurement with multiple imaging head using PSDHI

Abstract

The development of compact and conventional strain distribution measurement equipment for practical use is required for the evaluation of the health monitoring and the life-lengthening characteristics of infrastructures, such as steel bridges. Phase-shifting digital holography is a convenient method that can be used to measure displacement and strain distributions on the surface of an object. To simplify the optical setup is required for producing more compact equipment. An imaging head with four imaging devices was developed to producing more compact equipment by authors. The optical axis of each imaging sensor was directed to the object. Each imaging device can detects the phase difference distribution on the surface of the specimen. The four phase differences gives three directional displacement distributions and two directional strain distributions. In this paper, a prototype of a displacement and strain distribution measurement system with the multiple imaging devices is developed. The evaluation of the displacement and strain measurement with the prototype are shown.