Debut V, Antunes J
Instituto de Etnomusicologia, Centro de Estudos em Música e Dança, Departamento de Ciências Musicais, Faculdade de Ciências Sociais e Humanas, FCSH, Universidade Nova de Lisboa, 1069-061 Lisbon, Portugal.
Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal.
J Acoust Soc Am. 2020 Aug;148(2):575. doi: 10.1121/10.0001635.
Extending the previous work done by the authors, this paper develops a time domain synthesis method for the classical guitar based on substructuring concepts and using the Udwadia-Kalaba modeling strategy. Adopting a modal description of the dynamics of the separate flexible subsystems in terms of their unconstrained modes and enforcing coupling constraint conditions for the assembly, the result is an explicit dynamical modal formulation for the coupled system that directly lends itself to time-stepping methods for simulation. The guitar model couples six strings through an experimentally based body model of an actual instrument, includes two string polarizations, and the string geometrical nonlinear effects, as well as the string/fret interaction as the instrument is played. Details are given for putting all the vibrating components together in a satisfying manner, and a specific strategy is explored to allow for a nonrigid fret using flexible-dissipative-inertial constraints. The reliability of the approach is demonstrated with simulation examples that confirm the features one would expect regarding the dynamical behavior of classical guitars. Finally, a pragmatic approach is made to calculate the radiated sound by convolution, combining the computed bridge force with a measured vibro-acoustic impulse response of the instrument, which proved to give satisfactory sounding results.
在作者之前工作的基础上进行拓展，本文基于子结构概念并采用乌德瓦迪亚 - 卡拉巴建模策略，开发了一种古典吉他的时域合成方法。通过对各个柔性子系统的动力学采用基于其自由模态的模态描述，并对组装体施加耦合约束条件，得到了耦合系统的显式动力学模态公式，该公式直接适用于时间步长法进行模拟。吉他模型通过基于实际乐器的实验性琴身模型耦合六根弦，包括两种弦的极化方式、弦的几何非线性效应以及弹奏乐器时的弦/品丝相互作用。详细介绍了以令人满意的方式将所有振动部件组合在一起的方法，并探索了一种采用柔性 - 耗散 - 惯性约束来考虑非刚性品丝的具体策略。通过仿真示例证明了该方法的可靠性，这些示例证实了人们对古典吉他动力学行为所期望的特征。最后，采用一种务实的方法通过卷积计算辐射声，将计算得到的琴桥力与测量得到的乐器振动声学脉冲响应相结合，结果证明能给出令人满意的发声效果。
