抄録
Wear development with polygonal shape on a rotating elastic body is a kind of pattern formation phenomenon in mechanical vibration. The polygonal deformation occurs gradually, and this causes strong vibration and noise in machine operations. This phenomenon is a kind of self-excited vibration due to time lag and eigen characteristics gives an explanation of the stability of the system. This paper deals with the experimental approach of this pattern formation in order to discuss about the polygonal numbers of the shape, giving the various rotation speed and slip ratio. The effect of the disturbance given as a groove on the surface on the stability is also examined. It is pointed out that the unexpected polygonal number appears during the rotation in the case of the large disturbance.