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Model-Based Effects Screening of Stringed Instruments

  • R. VialaEmail author
  • V. Placet
  • S. Cogan
  • E. Foltête
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)

Abstract

Luthiery is a secular art of craftsmanship, consisting in the selection of the best pieces of wood chosen for their texture, tone, and appearance. These pieces are then carved and assembled according to traditional methods, transmitted from master to apprentice. Instrument makers, as well as scientists, have always been interested in the complex vibratory and acoustic behavior of these assemblies and have sought to understand the physical interactions between the bow and the strings of violins. Nowadays, virtual prototyping enables researchers to study complex structures in aerospace, industry, automotive domains, and is used since the late 1970s to study musical instruments, either to predict their behavior or to explore new shapes and materials for their construction. In this study, we have modeled an unmounted violin composed of numerous solids. As violins are made of wood, the inherent orthotropic properties have been implemented for the principle parts of the instrument. The modal behavior of the assembly has been computed and an effects screening analysis performed to rank the influence of the different material properties of each part with respect to their impact on the modal behavior of the whole instrument.

Keywords

Effects screening Violin Modal analysis Orthotropic material Wood 

Nomenclature

[S]

Compliance tensor

Sij

Component of compliance tensor in i,j directions

{σ}

Stress tensor

{ε}

Strain tensor

σij

Stress component in i,j directions

εij

Strain component in i,j directions

Ei

Young’s modulus in i direction

νij

Poisson’s ration in i,j directions

Gij

Shear modulus in i,j directions

ρ

Density

MC

Moisture content

RH

Relative humidity

[Yi]

Modal matrix of i set of mode

{yji}

Eigenvector j of i set of mode

L

Longitudinal

R

Radial

T

Tangential

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Copyright information

© The Society for Experimental Mechanics, Inc. 2016

Authors and Affiliations

  1. 1.Department of Applied MechanicsUniversity of Bourgogne Franche-Comté, FEMTO-ST InstituteBesançonFrance

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