Stick, slip... bounce? Influence of violin bow rotational inertia on bouncing strokes

Abstract

Prior perceptual tests using an experimental bow whose moment of inertia (relative to the pivot around the thumb) could be modified by moving small masses along the stick have indicated that violinists exhibit significant sensitivity to this parameter. This sensitivity was particularly notable when playing bouncing strokes like sautillé: some players reported perceiving a shift in the bouncing point, which refers to where the bow naturally bounces. Using the same experimental bow, we wanted to investigate further this influence of the bow rotational inertia. Through modal analysis, we examined the influence of moment of inertia on the bow's dynamic behavior. Additionally, a playing experiment involving motion capture was conducted on one player to explore how his control parameters were affected by a change of moment of inertia. This is of interest for bow makers as they can easily adjust the moment of inertia without affecting the stick's integrity by just varying the weight of the tip plate.