In context: While tires may never steal the spotlight from more glamorous automotive components, their importance and the sophistication of their development should not be underestimated. The marriage of advanced simulation and real-world testing promises to deliver safer, more efficient, and better-performing tires.
In the world of automotive engineering, tires often take a backseat to more exciting components. While car enthusiasts might obsess over horsepower figures and average consumers prioritize smartphone connectivity, it's the humble tire that serves as the crucial interface between vehicle and road. As Chris Helsel, Goodyear's Chief Technology Officer, succinctly put it to Ars Technica, "Without them, no one is going anywhere. At least not very far."
The tire industry has come a long way from the days when tire composition was shrouded in mystery. Today, companies like Goodyear have amassed vast amounts of data, allowing them to create highly accurate simulations that significantly reduce development time.
Helsel, who joined Goodyear in 1996 as part of a small team focused on computer tire simulation, recalls the early days of this technology. "At Goodyear in '96, it felt like almost late to the party in terms of doing what we call finite element analysis, which is basically breaking a large structure down into little parts," he said.
Simulating tire behavior is an incredibly complex task. Helsel described several challenges, including tire deformation, the tire-road interface, tire-rim contact, and the complexity of tread patterns. "A tire deforms 40 percent every time it rotates, so that huge amount of displacement, or change, causes those elements to displace, and that causes numerical instability," Helsel said. He also pointed to the difficulty of solving the friction equation at the point where the tire meets the road and accurately representing the intricate details of tire tread patterns in geometric models.
Over the years, tire simulation capabilities have expanded dramatically. From simply predicting contact patch shapes in the 1990s, Goodyear can now model tires in full fidelity, including various climatic conditions. Simulating snow conditions, for instance, can be very complex, Helsel said. "Snow is connecting, then it's breaking apart. That's a really challenging numerical problem."
Goodyear has taken tire simulation to the next level with the introduction of driver-in-the-loop simulators. It now has two – one in Akron, Ohio, in 2021, and another in Luxembourg in 2024. These advanced systems, similar to those used in motorsports, allow for dynamic tire testing without the need for physical prototypes.
These facilities have dramatically accelerated the tire development process. Helsel notes that in the late 1990s, tire development could require up to 10 physical iterations. With improvements in footprint simulation, this number was halved. The introduction of high-fidelity tire modeling and simulators has further reduced it to just one physical build and test confirmation.
This efficiency gain translates to significant savings in resources. Steve Rohweder, VP of Technology Development at Goodyear, estimates that the new process eliminates the need for approximately 13,000 tires and 60,000 miles of test track driving for each development cycle.
"We've done variation in studies with sizes when we're setting targets working with the manufacturer before they start the vehicle development," Rohweder explained. "Tire dimension is easy to adjust. Compound, major design changes – when you have the data and you prepare it, you can go into the simulator environment and quickly move around in the design space to find out what the driver feels is most effective and best for shooting on that target."