Vehicles of the future are being transformed today to meet the societal challenge of reversing climate change. Meeting zero-emission goals, increasing shared mobility and improving safety are some of the focal points. Car manufacturers and their supply chain are exploring, developing and implementing new technologies to meet the upcoming European regulations on safety. TNO at Holst Centre supports the automotive supply chain by bringing their expertise in flexible electronics to the table. Innovations in flexible electronic materials and processes enable new features in car interiors: transparent displays, safe and programmable interfaces and sensing chairs.
In an article published in the OPE-Journal of 3 March 2021, Lotte Willems explores the technologies behind these new features and how they can enhance comfort and safety in the cockpits of the future. An abstract is given below.
Blind spots become visible
To achieve 'zero road deaths and serious injuries' by 2050, new European regulations dictate that detection of vulnerable road users like pedestrians and cyclists by commercial vehicles should be improved. One of the main topics is reducing or even eliminating a truck's blind spot, where the field of view is limited. A future solution is the use of transparent signage or displays in the window of a truck. This innovation is enabled by the developments of very small pixels, the so called mini-and micro-LEDs in combination with transparent conductors and large-area, low-cost processing technologies.
Flexible LED foil from our fully automated roll-2-roll assembly line.
Another safety aspect of the upcoming European safety regulations is that they require detection of driver fatigue and alertness in all motorized vehicles. With sensor mats invisibly integrated in car seats, it becomes possible to unobtrusively monitor people's physical and emotional state. These sensor mats contain a dense grid of pressure and piezo sensors, allowing direct sensing of physiological parameters. We can now measure a driver's heart rate and respiration rate under driving conditions with a system that passed most automotive tests. We have also optimized the process to directly 'print' piezo and pressure sensors on highly conformable substrates, enabling low-cost, large-area sensors that can be unobtrusively integrated into the car seat. This technology is now on the verge of being scaled up to production level and can seriously contribute to a safer driver's experience.
Safe, personalised dashboard for shared mobility
In the near future, vehicles will be shared by multiple users to increase vehicle utilization and reduce the carbon footprint. These users, often from different generations and backgrounds, have different needs and preferences. Creating one dashboard or interface that meets the needs of all these different people is nearly impossible when physical buttons are used. The result would be an overcrowded console with a multitude of buttons, which would greatly inhibit its usability. That is why there is increasing interest in programmable interfaces. Programmable interfaces are available as conventional glass-based displays such as touch screens, but these typically take up a lot of space and do not allow for a seamless integration in the dashboard, impacting the look and feel of a car's interior. Innovations in technology known as plastronics or in-mould electronics pave the way for the invisible integration of flexible touch screens in dashboards.
Hybrid printed electronics
The core technology that enables transparent displays, safe and programmable interfaces and sensing chairs is 'hybrid printed electronics'. This is the ability to make electronic products by means of an additive manufacturing process where conductive patterns are printed on foils, combined with semiconductor components. Combining printed circuits and devices with traditional electronic components like LEDs and chips enables large-area, flexible and freeform applications that can be manufactured in high volumes using roll-to-roll printing and assembly processes.