Theoretical and Experimental Studies on 3D Vibration Measurement Based on Displacement-sensitive Fringe Pattern

Abstract

：A novel method for the measurement of structural three-dimensional (3D) vibration based on a displacement-sensitive fringe pattern (DSFP) and a high speed camera is proposed to overcome the simultaneous measurement problem in structural 3D vibration using monocular vision. Based on the established model of the proposed monocular vision measurement system, the measurement principle for structural 3D vibration is illustrated systematically. The relationships between the real 3D displacement and the 3D dynamics parameters obtained from the recorded DSFP image sequence is established. The formulas for calculating each dimensional displacement is also derived. The correctness of the displacement measurement principle and algorithm is verified by using the co-simulation model of structural 3D motion and monocular vision system. The performance and its influencing factors of the measurement system are evaluated by simulation and experiment. The experimental results for known structural 3D displacement and the contrast test results with the 3D acceleration sensor demonstrates the effectiveness of the proposed DSFP and vision based system in structural 3D displacement measurement.