Transients in circular symmetry; estimation of transverse wave propagation velocity

Author

Axmon, Joakim ; Hansson, Maria

Author_Institution

Dept. of Appl. Electron., Lund Univ., Sweden

fYear

2000

fDate

2000

Firstpage

212

Lastpage

216

Abstract

The response of a tree trunk to a hammer blow, measured by sensors positioned around the excited cross section, consists of two kinds of transient mechanical waves: longitudinal P- and transverse S-waves. The aim of this paper is to extract the velocity of the S-waves, using a filtering structure that emphasizes the waves heading in one of the directions along the circumference. By this approach, a more robust estimate of the delay between the channels, compared to, e.g., using the pure discrete Radon transform, is obtained. The method is applied to recordings of a large number of trees, and estimated velocities are reported

Keywords

array signal processing; delay estimation; elastic waves; filtering theory; forestry; transients; circular symmetry; decay detection; delay estimation; filtering structure; forestry industry; hammer blow; longitudinal P-waves; nondestructive testing; pure discrete Radon transform; transient mechanical waves; transients; transverse S-waves; transverse wave propagation velocity estimation; tree trunk; Clocks; Delay estimation; Force sensors; Forestry; Mechanical sensors; Mechanical variables measurement; Position measurement; Pulse measurements; Robustness; Sparse matrices;

fLanguage

English

Publisher

ieee

Conference_Titel

Sensor Array and Multichannel Signal Processing Workshop. 2000. Proceedings of the 2000 IEEE

Conference_Location

Cambridge, MA

Print_ISBN

0-7803-6339-6

Type

conf

DOI

10.1109/SAM.2000.878000

Filename

878000