Abstract: A method for determining preselected performance characteristics of a tread of a tire consists in dividing the tread in a grid of cells forming piles of cells which are full, empty or partially full; identifying a group of piles of cells in each contact area; determining longitudinal stiffness values cxj and transversal stiffness values cyj for each pile; identifying families of discrete areas and transversal strips in each contact area; determining, for each strip, forces per unit of length by means of cxj and cyj, longitudinal stiffness values per unit of length cpx and transversal stiffness values per unit of length cpy and by means of cpx and cpy and a preselected state of deformation; determining total forces associated with all contact areas by means of single forces associated with the discrete areas, and evaluating their pattern so as to establish whether the arrangement of full and empty cells optimizes the performance characteristics of the tread.

Abstract: A method and a device for reducing the internal noise of a vehicle produced during the rolling of the tire are described The device comprises a plurality of elements made from open-cell expanded materials, for example expanded polyethylene, or from fibers of the mineral or textile type. These elements are introduced into the tire during its mounting on the corresponding rim and are placed in the absence of restraints in the annular cavity delimited between the tire and the rim. As a result of the rolling of the wheel, the various elements, under the action of the centrifugal force, are moved and pushed in a random way towards the inner surface of the tire, producing a ragged surface whose presence, in combination with the open cells of said elements, modifies and damps the acoustic waves generated inside the tire during the rolling of the tire.