In the last of this year’s series of 30th anniversary look-back articles, TTI technical editor Joe Walter recalls his first encounter with the publication and how he wound up being such a consistent part of its identity.

When Tire Technology International (TTI) appeared on the scene 30 years ago, I arrived in Rome as the newly appointed head honcho of Bridgestone’s European Technical Center. The somewhat inconsistent Italian mail system was such that I would occasionally receive issues of the newly launched Tire Technology International Annual Review followed thereafter by the inaugural magazine – all during my five-year tenure as an Akronite living the dream in the Eternal City.

Continue reading OPINION: Joe Walter recalls his first encounter with TTI at Tire Technology International.

TTI’s technical editor explains why maintaining tire pressure remains a persistent problem in pneumatic tire design.

The persistent problem of the pneumatic tire is the never-ending lowering of internal pressure in otherwise robust components of cord and rubber. Inflation pressure drops continuously by a chemical process known as permeability while a temperature drop reduces pressure without loss of air mass (gas laws of physics). Relatedly, self-inflating tires (which stabilize pressure during roadway service) achieved some recent notoriety with a US$65m jury award to Coda Development against Goodyear in September 2022. The case centered on patents, trade secrets and non-disclosure accords; the Prague-based plaintiff alleged Goodyear stole its ideas for self-inflating tire technology.

Continue reading Opinion: Joe Walter  at Tire Technology International.

Fossil fuels collectively supply about 85% of today’s world energy; of this amount, transportation powered by petroleum produces 25% of man-made atmospheric carbon dioxide – a greenhouse gas contributing to global warming. Consequently, petroleum is facing threats from renewable energy sources, climate change concerns, EV usage and politicians sometimes promoting pseudoscientific environmental policies. It seems that future undertakings directed at decarbonizing transport will be driven mainly by government legislation and mandates, not by consumer preferences or diminished petroleum supplies. The tire industry will not be immune to these pressures, but the movement toward sustainable mobility could be problematic for tire manufacturers and their suppliers.

Continue reading Sustainable tire materials at Tire Technology International.

Pneumatic tires always roll with slip unless traveling straight ahead with their loaded rolling radius coinciding with their effective radius – an infrequent circumstance. Slippage in the contact patch is further exacerbated by vehicle braking, driving and/or cornering. Even tires rolling and turning at low speed on a dry surface will undergo overall longitudinal slip and lateral scrubbing coupled with individual tread element squirm. Such relative motion between tires and roads promotes tread wear. To help minimize unnecessary tire sliding during vehicle cornering, a four-bar linkage with an isosceles trapezoid planform, or Ackermann geometry, is generally used as the foundation for front-wheel steering control.

Continue reading The story of Ackermann steering at Tire Technology International.

The pneumatic tire is a rotating air spring continuously compressed in the region of road contact during each revolution. The pressurized air inside the tire’s toroidal chamber is principally composed of a mechanical mixture of two diatomic gases, nitrogen (78%) and oxygen (21%), plus trace amounts of a whole host of other gases – some quite exotic. Often forgotten is the fact that an inflated tire is a pressure vessel with the compressed air governed reasonably well by the gas laws of physics. Accordingly, air under pressure possesses a large amount of stored energy which, if released instantaneously, can rupture the tire with explosive force.

Continue reading Never forget that a tire is a pressure vessel at Tire Technology International.

Surprisingly, composite and/or laminated materials used in manufactured goods predate the founding of ancient Rome. 
For example, 3,500 years ago, the Egyptians improved the durability of mud bricks by adding chopped straw to a matrix of soft clay prior to molding and drying. Similarly, plywood (adhered laminated veneers of cross-grained wood) has 
had a millennial history. However, it was not 
until the 1930s, with the development and use 
of synthetic phenolic adhesives in place of animal and plant glues, that laminated wood materials emerged as load-bearing, waterproof structures. The British de Havilland Mosquito combat airplane 
of World War II featured such bonded plywood wings, among other components.

Continue reading TTI technical editor Joe Walter discusses how a tire’s design makes it more than the sum of its parts at Tire Technology International.

The likelihood of a car being struck by lightning during a thunderstorm is extremely low, but when it happens, unusual and unpredictable outcomes unfold. Normally, a cloud-to-vehicle lightning bolt will strike either the vehicle antenna or the roofline – although direct hits on tire-wheel assemblies have been reported. The lightning strike could destroy one or more tires, which sometimes ignite or explode as the electric charge passes to the ground. However, vehicle occupants remain safe since automobiles (as well as trains and airplanes) are essentially Faraday cages that protect travelers by safely passing the lightning’s charge through the vehicle’s outer metal shell.

Continue reading Could conductive carbon allotropes be applied in rubbers that can harvest electromechanical energy from electrified tires? at Tire Technology International.