Abstract
The authors previously developed a dynamic model based accurate pipe length measurement system using stationary waves generated spontaneously or by hitting the pipe. However, two problems rise when the system is applied to the length measurement of steel pipes at factories. The first is that a considerably large noise is continuously generated around the measuring spot and thus it causes low SN ratio in the observation. The second is that high order modes of the stationary wave cannot be available because the diameter of the steel pipes is relatively large compared to the pipe length. This paper thus proposes an accurate length measurement of a pipe under noisy environment by considering the selections of an optimal sensor location and an optimal data window.
