This is the readme for the "struck_bar_material" PD model of the impact interaction on a modal resonator tuned according to the theory of a clamped bar (see e.g. Morse, P. M. and Ingard, K. U.: Theoretical Acoustics, Princeton U. P. 1968, Princeton, NJ, pp. 175 191).
The decay times are connected to the according frequencies via two friction parameters, external and internal friction. The latter one has been suggested as an approximate shape-independent material characteristic (R. Wildes and W. Richards: Recovering material properties from sound. In W. Richards, editor, Natural Computation, pages 356 363. MIT Press, Cambridge, MA, 1988)
The strategy has been used (K. van den Doel, P. G. Kry, and D. K. Pai. Foleyautomatic: Physically-based sound effects for interactive simulation and animation. In ACM SIGGRAPH 2001, August 2001) and tested (R. L. Klatzky, D. K. Pai, and E. P. Krotkov. Perception of material from contact sounds. Presence: Teleoperators and Virtual Environment, 9(4):399 410, August 2000) before, but is here connected with a physically-based model of impact interaction, instead of simple impulse-input or assumed force-profiles. Increased realism and expressiveness is thus achieved, see also SOb deliverable 6.



The development was part of the activities of the SOb(SoundingObject)-project.



To run the patches, you must use pd version 0.33 or later.
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For questions, comments, suggestions don't hesitate to contact rath@sci.univr.it; examples of realized sounds of whatever (e.g. musical) use are particularly welcome.

Verona, july, 13th, Matthias Rath
