Printed electronics: more safety and comfort in automobiles

The electronic control systems including several miles of cables that are installed in a premium car weigh about 550 pounds. An end to this is now in sight because the automotive industry is increasingly relying on printed electronics.

“Printing processes can be used to manufacture sensors and many other electronic components, some of which are thinner than a tenth of a millimetre,” said Dr Alain Schumacher, CTO of IEE Luxembourg, Vice Chairman OE-A Europe, and speaker at the 2020 LOPEC Conference.

IEE has evolved from a three-person start-up to one of the market leaders for printed sensor technology in the automotive industry. “In research, development and production, we have relied on printed electronics right from the start,” added Schumacher. In his plenary lecture at the LOPEC Conference, he will discuss the success story of IEE and the diverse applications of printed electronics.

Schumacher: “Printed electronics can be placed in the immediate vicinity of or even exactly where they are needed in the car.” 

There is no need for time-consuming cabling and there are hardly any limits to the design, as, due to their properties—thin, lightweight, flexible, stretchable and transparent—, printed electronics can be integrated into surfaces and components of almost any shape. Another advantage is the cost-efficient production with printing processes suitable for volume production. 

The range of inks, pastes and carrier materials required for this has been expanded enormously over the recent years. In addition to manufacturers and users of printed electronics, material developers and plant manufacturers will be presenting their innovations at LOPEC.

The automotive industry already uses printed electronics as standard, for example in systems reminding people to fasten their seat belts or controlling the deployment of airbags. Printed seat occupancy sensors are integrated into the seat surface and generate an electric signal when deformed. 

“The technology was originally developed to ensure that an airbag is deployed only when someone is actually sitting in the seat,” explained Schumacher. Meanwhile, the sensors even detect child seats and, via integrated antennas, can detect the direction in which a baby seat has been installed.

Seat heaters printed on film with conductive inks also make vehicles safer and more comfortable at the same time. They offer several advantages over the previously common filaments: They are easier to integrate into car seats, warm more evenly and save energy. What is more: “The maximum temperature can be determined through the composition of the ink. Dangerous overheating is thus made impossible,” said Schumacher. 

The heating films are now to be increasingly used in electric cars, as their motors do not produce any significant waste heat for a heat exchanger. Heating films in side panels and other surfaces solve this problem.

With the trend towards autonomous driving, the interior of vehicles is changing fundamentally anyway, because drivers hardly have to concentrate on traffic anymore. The interior is therefore intended to provide relaxation at times and an office environment at others. The visions range from sensor-controlled OLEDs for individual lighting concepts to flexible displays to 3D cinema. There is no way around printed electronics for reasons of weight and space, but above all because they are easy to integrate.