Abstract: A method and apparatus for video imaging of a tire ground contact patch or tire footprint is presented. A digitized image of the footprint is generated as an array of pixels. Each pixel is attributed a binary value of one or zero, to present a two-valued image. Contact areas within the image are attributed a first value, while void or noncontact areas are attributed a second value. The image is then dilated and eroded in an appropriate sequence to eliminate all white pixels from the image and to eliminate surface anomalies or the like which are not of interest in the tire analysis. An image of the footprint, accurate in size and dimensions, is thereby generated and, from such footprint, total area, contact area, and void area can be determined, as well as measurements of width, center line length, and other desired lengths at various lateral width locations. This data may be used to analyze the tire construction, operation, noise generation, and performance.

Abstract: A heavy duty radial tire includes at least one radial carcass extending from one bead portion to the other bead portion and using inextensible cords and a belt arranged outwardly of the radial carcass for reinforcing a tread of the tire. The tire comprises, during expanding of the tire from 5% to 100% of a normal inner pressure, a first profile portion expanding radially outwardly in a tread zone, a second profile portion depressing axially inwardly of the tire in a radially outer zone of a sidewall from one end of said tread to a tire maximum width position when filled with the normal inner pressure, and a third profile portion expanding axially outwardly of the tire in a radially inner zone of the sidewall from the tire maximum width position when filled with the normal inner pressure to a parting point of the sidewall from the rim, thereby properly distributing strains occurring in the tire in filling with the normal inner pressure.