Acoustic Research Tool (ART) - A Simulation Framework with Modelling Library for Acoustic Systems
Copyright (C) 2011 by the authors and their organisations:
Alistair Braden 1)
Wilfried Kausel 2)
Delphine Chadefaux 2)
Vasileios Chatziioannou 2)
Sadjad Siddiq 2)
Clemens Geyer 2)
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
In 2002 Jonathan Kemp published his thesis "Theoretical and experimental study of wave propagation in brass musical instruments" (Univ. of Edinburgh) containing a comprehensive review of the theory of multimodal wave propagation and extending it to include ducts with rectangular cross-section (ready to be implemented).
The basic concepts for the simulation framework of the ART project have been presented at the ViennaTalk 2005 by Wilfried Kausel, who founded the WG2 at the subsequent TCMA meeting in Budapest in order to trigger an international collaboration for the collection of existing and future physical models with the aim of integrating them into a common framework to make them more generally available and useful.
In 2006 Alistair Braden contributed the first C++ code as part of his thesis "Bore Optimisation and Impedance Modelling of Brass Musical Instruments" (Univ. of Edinburgh). He extended the theory of multimodal wave propagation to include bent cylindrical tubes and he implemented straight and bent cylinders and cones, bessel horns, exponential sections and bore discontinuities. His code was ported to Windows by Kausel who also optimised its performance and included local simulation parameters like temperature and boundary loss factor. He also started to create the application interface layer by adding the parameter dependency tree and by implementing the "self- documentation feature" of all available models and parameters.
During an internship at the University of Music in Vienna Delphine Chadefaux added branch elements (tone holes) and she implemented the "matrix accumulation concept" as an optional alternative to the "impedance back-propagation concept" which turned out to be numerically more stable and which allows to cache the system matrix of a bigger section of the bore profile (e.g. the bell) when this is not to be modified during series of impedance recalculations. She also improved the model for the speed of sound in air taking relative humidity and carbon dioxide content into account.
In 2009 Vasileios Chatziioannou became a member of the acoustic research team at the University of Music in Vienna and he is now in charge of the simulation kernel. He improved the code significantly by fixing many remaining bugs, straightening out and documenting the code. He also added the thermo-viscous loss model of straight tubes to the bent tube and cone sections which were lossless before.
Since March 2011 Sadjad Siddiq has been working on the programmers' interface. He implemented the caching algorithm, integrated the expression parser, introduced the wave objects and models interface and compiled the documentation.
Clemens Geyer, a master level student at the University of Music in Vienna, is currently checking and reestablishing the GCC- and Linux compatibility and is going to add time domain processing to the simulation core.