The 3D Particle Tracking Velocimetry(PTV) offers a flexible technique for the determination of structural motion. In the past decade the research work determinate the structure motion by contact type measurement system. But contact type measurement system contains a basic error by contact equipment. In this paper, we measured motion of circular cylinder type structure using PTV measurement system against the traditional measurement system. And we decided that PTV method is suitable for detection of structural motion through the comparison.
And the results show that each experimental value are good agreement. But theoretical value are bad agreement with experimental value except heave motion. This disagreement was caused by coupled motion of pitch and surge motion.