The future of tires (according to someone who knows)
Tires have evolved dramatically in the last few decades, thanks to research and investment by tire manufacturers, academics and innovators. From high-performance and all-season to run-flats and tires made with dandelions and orange oil products, the industry is constantly seeking out bigger and better ways to improve on a product that first emerged more than 100 years ago.
So how has the industry changed and what does the future hold for the not-so-humble tire? Traction News asked one man who is undoubtedly an expert in the field, Center for Tire Research (CenTiRe) managing director Dr. Ron Kennedy.
With a doctorate in mechanical engineering and 37 years’ experience working in research for Firestone, Bridgestone, and Hankook Tire, Kennedy took up his current role as managing director two years ago. Here he talks to Traction News about the greatest innovations to date and predicts the rise of the “intelligent” tire.
Tires have evolved immensely; can we really improve them much more?
Engineers, chemists, and scientists at the tire companies have done a tremendous job improving the performance of tires over the years. Tires today are more fuel efficient, more durable, provide better traction and are quieter than they were 10 years ago. However, there are continuing demands for additional performance improvements driven by customer needs and desires, government regulations, tire labeling requirements and the tire industry’s own desire for product differentiation and improved market share. These will continue to drive the improvement of tires.
In the U.S., government Corporate Average Fuel Economy (CAFE) requirements are specifying a large improvement in vehicle fuel economy by 2025. Although it is a vehicle mandate, the requirements are providing a push for significant rolling resistance improvements in tires. Of course, the tire companies cannot ignore other tire performance such as traction (dry, wet and snow) in their pursuit of improved rolling resistance. All phases of tire performance must be maintained, if not improved. This makes technical improvements in tires a given.
This improvement in tire performance to meet the needs of customers, government regulations, labels and company marketing cannot be done by only one aspect of tire design. Continuous improvements in tire materials, compounding, construction and tread design must be made.
The tire does not act alone in providing the desired handling, traction or noise performance. Interactions with the vehicle are important and so tire and vehicle manufacturers are working together to improve the compatibility and integration of their products to give the best overall performance. Cooperative, synergistic work between a tire company and vehicle company will continue to be important going into the future.
What’s changed in tire research and development during your career?
I started my career in the tire industry in 1977 as the radial tire was making strong inroads into the U.S. market. At the time the tire industry was going through the learning curve on how to best manufacture the tires and take advantage of the performance improvements that could be made with the radial construction.
Over the years the materials and compounding have evolved with better understanding of the chemistry to modify or add to the polymer molecular chains, introduce fillers so they enhance the compound performance more effectively and reduce the emission of volatile gasses. Chemists and scientists at the tire and materials supply companies have expanded beyond their lab experimental studies to performing computer modeling and simulation at the molecular level to study and make improvements in the materials and compounds. This allows them to investigate and probe in ways that are not possible in the lab.
Tire simulation, doing virtual design and testing on the computer, was in its infancy when I started my career in the tire industry. It was a big deal to be able to simulate rim seating, inflation and static loading against the ground. Now engineers perform simulations of the tire design and manufacturing process, and the full range of tire performance testing. For example, the simulation of various tire design candidates on a vehicle traversing a handling course is routinely done before any tires are manufactured. Ongoing research work is being done to make these simulations more realistic and accurate to enhance the tire engineers’ ability to make evaluations of potential designs before molds are ordered and tires manufactured.
Since I started in the tire industry in the late 1970s, the biggest innovation in tire design that has made a significant and lasting dent in the tire market has been the run-flat tire. The development of the run-flat tire went through many evolutions in design approaches (e.g., inner support rings versus sidewall inserts) and refinements over almost 20 years before it gained acceptance as an OE fitment in the mid-1990s. It required the development of specialized materials, design concepts, manufacturing techniques and testing procedures to make it a viable product.
What’s been the most important development in tire design in the past 50 years?
The most important development in tire design has been the dual improvement in rolling resistance and traction, as improvements in these are traditionally mutually exclusive. This has allowed the meeting of fuel savings requirements while improving the overall safety of the vehicle. This was accomplished through work on all aspects of tire design — materials, compounding, construction and tread pattern.
What innovations can we expect to see in the coming years?
Rolling resistance and traction continue to be a strong customer desire as well as areas of government regulatory interest, and so innovations in materials will be made to address these concerns through development of new polymers and improvements in the interaction between the polymer and fillers. Although the results may appear to be evolutionary increments, there are fundamental scientific investigations being conducted to underpin and guide the improvements.
Technology for intelligent tires is being developed to sense more than inflation pressure and temperature. Sensors within the tires, along with algorithms to interpret and transmit the measured data, will make the tire an integral part of the vehicle’s intelligent system. For example, being able to determine the friction between the tire and road surface via measurement of tire responses can be fed to the electronic stability or traction controller to make the vehicle safer.
Many tire companies have been working on non-pneumatic tire designs over the past decade. The results of this work have led to some currently available products that are focused on low speed, commercial fitments such as fork trucks or similar vehicles. However, work continues on development for automobile applications.
What will be the next big breakthrough in tire design?
I think development of an operational and marketable intelligent tire will be the next important breakthrough. This will contribute to the safety and performance of the tire and vehicle as it is driven through its various driving conditions. It will also contribute to the effectiveness of autonomous vehicles by providing better and more timely information of the conditions between the tire and the road, responses to road surface impacts and anomalies, and sensing of any tire issues since there will be no, or very little, interaction between a driver and the vehicle.