To gain insight into how the tire industry perceives the tire of tomorrow, Rubber & Plastics News surveyed a handful of major tire makers, asking about a number of game-changing aspects of tire design.
Bridgestone Americas Inc.; Contintental Tire the Americas L.L.C.; Cooper Tire & Rubber Co.; Goodyear; Hankook Tire USA; Michelin North America Inc.; Pirelli Tyre S.p.A.; and Sumitomo Rubber North America responded. An abbreviated version of the tire makers' answers to our questions appeared in the June 11 print issue of Rubber & Plastics News. The manufacturers' full responses to the questionnaire are being presented online as a three-part series.
This is part three of that series.
Q: Cyber tire? How widespread will integrated tire/vehicle technology be? What performance characteristics will be monitorable? Urgency from OE partners to develop in this direction?
BRIDGESTONE: As the only components of a vehicle to connect with the road surface, tires will become an important source of information for vehicles of the future. Everything from inflation pressure and tread depth to road conditions and the environment a vehicle is in will be monitored and reported as part of a connected vehicle ecosystem, and this information can be shared among vehicles and fleets.
You can expect to see automated sensing technology and the insights it produces leveraged first in the commercial tire segment. In fact, Bridgestone has been integrating sensors into its off-the-road tires for some time. The Bridgestone B-TAG system and TreadStat Tire and Rim Management technologies work together to monitor tire pressure and temperature and report that data to OTR customers in real time. This real-time reporting allows customers to make informed decisions and proactively address potential issues before encountering costly down time.
Bridgestone also is at the forefront of developing and implementing passenger tire technology that can determine road surface conditions based on the concept of Contact Area Information Sensing (CAIS). CAIS technology uses the tire's contact patch to analyze changing road conditions and share that information with the driver, helping to promote driving safety.
In the future, the industry will build on today's technology to develop intelligent tires with sensors that provide the autopilot with road condition information for safe operations in autonomous vehicles.
CONTINENTAL: Continental is introducing two tire technology concepts that will make for even greater road safety and comfort in the future. The two systems enable continuous monitoring of the tire's condition, as well as situation-matched adaptation of tire performance characteristics to prevailing road conditions. The technologies, called ContiSense and ContiAdapt, made their public debut at the 2017 Frankfurt Motor Show (IAA), accompanied by a tire study.
ContiSense is based on the development of electrically conductive rubber compounds that enable electric signals to be sent from a sensor in the tire to a receiver in the car. Rubber-based sensors continuously monitor both tread depth and temperature. If the measured values are above or below predefined limits, the system at once alerts the driver. If anything penetrates the tread, a circuit in the tire is closed, also triggering an immediate warning for the driver — faster than the systems used to date, which only warn the driver when the tire pressure has already begun to fall. In the future, the ContiSense system will feature additional sensors that can also be utilized individually. Thus information about the road surface, such as its temperature or the presence of snow, can be "felt" by the tire and passed on to the driver. The data can be transmitted to the vehicle electronics or via bluetooth to a smartphone.
ContiAdapt combines micro-compressors integrated into the wheel to adjust the tire pressure with a variable-width rim. The system can thus modify the size of the contact patch, which under different road conditions is a decisive factor for both safety and comfort. Four different combinations allow perfect adaptation to wet, uneven, slippery and normal conditions. For example, a smaller contact patch combined with high tire pressure make for low rolling resistance and energy-efficient driving on smooth, dry roads. By contrast, the combination of a larger contact patch with lower tire pressure delivers ideal grip on slippery roads. The system also permits very low tire pressures of below 1 bar to be set, to help ease the vehicle out of a parking space in deep snow, for example, or traverse a dangerous stretch of black ice.
ContiSense and ContiAdapt are joined by a concept tire that enables the benefits of both systems to be fully leveraged. The tire design features three different tread zones for driving on wet, slippery or dry surfaces. Depending on the tire pressure and rim width, different tread zones are activated and the concept tire adopts the required "footprint" in each case. In this way, the tire characteristics adapt to the prevailing road conditions or driver preferences.
Continental considers both these tire technology concepts promising solutions for the mobility of the future as tires are adapted to meet the needs of automated driving and electrification. Low rolling resistance, for example, makes it possible for electric cars to cover greater distances on a single charge. At the same time, the tires can be adapted to suit the driver's personal preferences or in response to sudden changes in the weather.
These concepts are the logical next step in the future-oriented development of the REDI sensor, brought to market by Continental in 2014, which was instrumental in establishing smart communication between vehicle and tire. The new tire technology concepts follow on from the two established mobility technologies ContiSeal, for the automatic sealing of punctures, and ContiSilent, for a tangible reduction in tire/road noise. Able to draw on more than a century of experience in tire technology and with in-house expertise in the fields of vehicle electronics and automotive IT, Continental is systematically aligning its products with the future requirements of autonomous driving and electric mobility.
COOPER: Related to autonomous fleet vehicles, tire sensors will be a requirement for tires used in this application. Basically, the "smart tire" will become a component integrated with the vehicle system, linked with other components that provide electronic readings.
HANKOOK: Automotive technology has transformed in a similar manner to that of many electronic household appliances through linkage to Big Data and self-driving capabilities. These technical changes enable tires to share information. Manufacturers currently are developing sensor technology to measure tires' internal data and share it with the Cloud. Tire companies are exploring ways to use this collected resource in marketing, R&D and production management.
Unprecedented progress is occurring through Intelligent Tire, uncovering new concepts while maintaining tires' current levels of functionality. Research and development is underway regarding various functions of Intelligent Tire sensors, detecting such factors as tire pneumatics, tire ID function, individual tire load, tire wear level, road surface condition and tire abnormalities.
Pneumatic monitoring techniques and Tire ID function have been commercialized previously. Air pressure monitoring techniques can currently be offered by TPMS, which is now mandated for automobiles released here and overseas. Also, Tire ID function can tell if the equipped tires are appropriate for the automobile or weather by sensing an automobile's operating condition and temperature.
Estimation is the core of Intelligent Tire. This technology estimates load and wear level by measuring presumable contact points between terrain and parts of the sensor. Proper weight control of a vehicle and changing the loading position are possible through commercialization of the technique, by detecting not only weight of vehicle but also the most loaded tire.
OE partners demanded the need for the development of intelligent tires, but intelligent tires are not just equipped on OE and autonomous vehicles. Even if autonomous vehicles and sharing economies are vitalized, drivers will still remain and intelligent tires will not only present the optimum navigational information, but also analyze driving patterns to provide a top-notch driving experience.
MICHELIN: All major OEMs are working in this domain and progressively implementing [automatic emergency braking, adaptive cruise, etc]. Tires are only part of the vehicle touching the road and don't currently have an edge sensor. The beginning of integration will include both tire identification and advanced sensing capabilities. Tire traction, wear, and handling response are all being research actively today.
PIRELLI:
• Application of sensor technologies and the accompanying development of smart, intelligent and cyber tire technologies is one of the most exciting ways in which tires will develop. The move to connected and automated cars requires the collection and processing of data regarding many aspects of the tire performance and road conditions. The same requirements exist for optimizing overall performance, safety and minimizing energy consumption, especially with regard to electric vehicles.
The tire is the only part in contact with the road and so is uniquely placed for gathering much of the crucial information that will be required (e.g. pressure, vertical load, tire wear, etc.).
• Features of sensorized tires are also developed to match current and future OEMs requirements.
SRI/FALKEN: As vehicles become more capable in terms of sensing and controlling how the vehicle moves and stops, the need for integrating more tire performance information into the system is necessary. The integration of tires with vehicles will be greater than today. This does not mean every tire will have sensors built into them within 10 years, but the collaboration between the tire and vehicles systems certainly will increase.
Vehicle makers are already using systems that utilize information about tire performance and years. ABS braking systems are one example, but we will see much more work in this area in the coming decade.
Q: Any developments pertaining to the tire/wheel interface — or integrated tire/wheel — that could influence tire design?
BRIDGESTONE: We are working across our global footprint to deliver solutions for a connected tire and wheel interface, and our recent strategic investment in ClearMotion is one example of this effort.
ClearMotion's active ride road-sensing technology is one way Bridgestone is leveraging our leadership in tire, anti-vibration and air spring technology to develop more advanced, integrated mobility solutions that deliver significant improvements in safety, performance and ride comfort. As the single tire and rubber manufacturer invested in ClearMotion, we believe this type of integrated, forward-looking technology offers tremendous opportunities for growth in automotive mobility.
CONTINENTAL: The current tire/wheel interface has proved its performance and reliability over decades. Workshops all over the world have installed machinery for mounting and dismounting of tires. A significant change in the tire/wheel interface would make this machinery obsolete and is therefore a big hurdle.
COOPER: No response
MICHELN: Working together with wheel maker Maxion Wheels, Michelin has developed a hybrid wheel — dubbed "Acorus" — which incorporates rubber expanders fitted to a slightly narrower wheel that connect the wheel body with the wheel flanges to help the tire/wheel package resist impacts more effectively.
When a vehicle suffers an impact (such as a pothole), the expander extends and safeguards both the tire and the aluminum section of the wheel. This reduces the risk of puncture caused by pinching the tire's sidewalls, and helping drivers avoid punctures will result in fewer premature tire replacements and a reduced need for raw materials.
HANKOOK: No response
PIRELLI: The tire/wheel interaction is a very important factor affecting the performance of a tire and therefore is subject of continuous study even by means of virtual modeling, fully integrated in the tire design process.
SRI/FALKEN: The change of tire performance as the tire wears is an area we will see more focus on in the future. As vehicles are built to react to driving situations based on their own computer sensor driven decisions, the change of tire performance as the tire wears will become measured, and work will be done to develop new tire technology to either communicate the change, or to mitigate it.
For example, TV commercials show vehicles braking on their own in emergency situations actually coming to a complete stop on their own, without driver engagement. How hard to apply braking power or when to apply it could change if tires with different capabilities are placed on the vehicle. Likewise, if the tire performance changes beyond a certain range as the tire wears the same issue could result. This could influence tire technology in the future.
Q: Pneumatic vs. non-pneumatic: Will non-pneumatic development catch up to pneumatic? What market niches might lend themselves to non-pneumatics? (eg: Autonomous cars in dense urban settings, where speeds are limited.)
BRIDGESTONE: Designing a practical, reliable non-pneumatic tire solution for consumer and commercial applications is an area of incredible opportunity for the future. As tire manufacturers work to address this need, the market is already seeing non-pneumatic solutions in the UTV segment. Bridgestone has been engineering improvements in non-pneumatic tire technology for a number of years. We believe this area will be increasingly important, particularly as autonomous vehicle technology and the need for durable and reliable tire solutions continues to evolve.
CONTINENTAL: Non pneumatic tires have a systematic disadvantage in rolling resistance, if a defined size of the contact catch is required for the force transmission. Niches, where rolling resistance and/or contact patch size are of lower importance, maybe appropriate for non-pneumatic tires. The need for low energy consumption of most vehicles (and the tire contribution) will hinder the penetration of non-pneumatic tires in the mass market.
COOPER: While some use could be seen for slow speed, in-city specific vehicles, the widespread use of non-pneumatic tires will require changes in vehicle suspension systems.
HANKOOK: Non-pneumatic tires differ from pneumatic tires in that they implement their functions not using tire pressure unlike other normal tires, but instead structurally bearing the vehicle's weight.
Therefore, there is no need for drivers to periodically check their tire pressure. These tires fundamentally prevent accidents stemming from contaminants causing damage or lowered tire pressure. This kind of safety is the biggest advantage of non-pneumatic tires, and it could further change the technology paradigm. Of course, pneumatic tires also are equipped with Sealant Tire, RFID (radio frequency identification), TPMS (tire pressure monitoring system) and sensor technology for safety reasons in case of tire pressure loss, but the key point is that non-pneumatic tires do not require tire pressure at all times.
Many tire companies are doing research on non-pneumatic tires; however, no product has been made public to actually replace pneumatic tires. Of course, some products with similar driving environments such as the lawn mower, golf cart, ATV (all-terrain vehicle) and heavy equipment (skid-steer loader type) have been released in the market.
It is irrefutable that non-pneumatic tires' biggest advantage is safety, but the noise, vibration, aerodynamic functions and safety in extreme situations are all challenges that must be solved. However, just like radial tires — which are used universally at present — took 50 years to settle in the market, non-pneumatic tires will enter the market soon, as their development is booming now.
To fulfill this, technology from other industries needs to be combined with current technology to improve non-pneumatic tire technology. Non-pneumatic tires are starting to be applied to lightweight vehicles, vehicles used in specialized industries, driverless cars and city cars. If material techniques, structural design techniques and hybrid technology are fused together, non-pneumatic tires will be able to replace pneumatic tires. It is certain that non-pneumatic tires' market share will increase, but there are still numerous technology hurdles to resolve until they entirely replace pneumatic tires.
Hankook Tire has led the development of non-pneumatic tires through a tire that uses cutting-edge technology. Named iFlex, the tire shows good durability, hardness and safety and has passed slalom and high speed tests. The iFlex uses urethane UNI-material, an eco-friendly material. The UNI-material consumes less energy in its design and production stages. Recycling is also easy.
MICHELIN: There is interest in robust solutions like Tweel as it relates to new mobility solutions for urban solutions. Tweel systems are currently on the market for vehicles which are not used on the road, but off road. Examples include lawn mowers, skid steer loaders, and UTV's.
PIRELLI: Such solution, today mostly at show tyre/prototype development phase, will need future improvements in design and material performance, and is most likely to first appear on "city" vehicles intended for relatively low-speed.
SRI/FALKEN: I do not believe we will see non-pneumatic tire performance catch up in the near future. Vehicle weights and speeds limit the use of current technology, and consumers are more concerned with cost today than performance, limiting what they will pay. This limits the ability to pass along new material creation costs and research and develop expenses.
As you point out, we may see niche applications, however, it may be quite some time before we see the demise of the pneumatic tire.