Printed electronics technology for ADAS, EVs, AVs

Features - Features

Schreiner ProTech’s president discusses how thin-film technologies support advanced sensors, protect against electromagnetic interference (EMI), and offer communications advances.

thin films
Film heaters reliably keep interior and exterior onboard sensors free of fogging, ice, and snow.
Photos credit: Schreiner ProTech

From electric vehicles (EVs) to fully autonomous vehicles (AVs): mobility is in a state of transformation. The basic need for personal mobility is a growth market, and self-driving EVs that reduce environmental impact combined with crash avoidance are the future. The day will come when we’ll be able to get into a car, tell it where we want to go, and arrive there without taking any action ourselves. Mobility offerings are becoming more extensive and diverse, with innovative technologies affecting how vehicles are designed, constructed, and maintained. EVs have components such as charging systems, new kinds of electronic control units (ECUs), and traction batteries that vehicles with internal combustion engines (ICE) don’t use.

However, like those in gasoline- or diesel-powered vehicles, these components require reliable marking, connecting, and pressure compensation. Alongside electrification, autonomous driving is gaining momentum, which has its own challenges. A basic prerequisite for these technologies is the use of onboard sensors, which must be reliable in all weather conditions.

Advanced driver assistance systems

An example of how the human body works illustrates how AVs operate: our eyes and other sensory organs acquire environmental information and transform it into electrical impulses. Our brain, the human control center, processes these electrical impulses and calculates the required activities. The results of these calculations are transmitted as electrical impulses to our hands, legs, etc. that subsequently perform activities such as braking or steering.

Autonomous driving works similarly: a car must respond to its environment and simultaneously communicate with its surroundings. Sensors in advanced driver assistance systems (ADAS) are indispensable for autonomous driving, and various technologies help cars see the world around them. ADAS can recognize critical situations early on, warn drivers, and if necessary, actively intervene in ways analogous to human intervention. However, they’re superior to humans in this context because, statistically, 90% of all traffic accidents are caused by human error.

Pressure-compensation seals ensure reliable ADAS performance. The highly sensitive measuring and control technology uses pressure transducers to convert applied pressure into a mechanically or electrically measurable signal. These components frequently endure exceptional environmental effects that cause stress. Consequently, the installed electronics require reliable protection against rain, splash water, oil, or salt combined with optimal pressure compensation.

Pressure compensation seals with their membranes are customized to suit specific applications and offer size flexibility.

Protection films

Avoiding damage from electromagnetic waves is another increasingly important issue. The growing number of electronic components installed in automobiles entails greater complexity in the context of ensuring electromagnetic compatibility (EMC). With inadequate shielding, electromagnetic waves and electric fields generate unwanted voltages and currents. Results can include audible humming, impaired performance, and signal interferences (sensors failing to communicate with ECUs). In addition, there’s higher risk of fire due to overloading.

Electromagnetic interference (EMI) shielding films, such as those supplied by Schreiner ProTech, reduce risks resulting from electromagnetic radiation. Films consist of electrically conductive materials, such as metalized films, metallic foils, metalized foam, or metallic fabrics. The radiation frequency is a key criterion for selecting the shielding film: the lower the frequency, the longer the wavelength and greater the penetration depth of the radiation.

New systems

Camera, radar, or light detection and ranging (LiDAR) systems all have one major aspect in common: they must deliver perfect performance in all weather conditions. Cameras and sensors must be de-iced and defogged before driving a vehicle and kept ice- and fog-free while it’s on the road. Only heaters can accomplish these tasks.

Film heaters based on printed electronics can be installed and operated directly adjacent to the sensor. These functional films are lightweight, flat, and flexible, so they can be mounted near the sensor in an extremely small space. The films deliver heat homogeneously or inhomogeneously for reliable de-icing and defogging. The flexibility of the films and variable design of conductive tracks allow film heaters to be customized to suit the shape, size, and curvature of the component.

Pressure compensation seals and film heaters function well, even in inclement weather or on steep inclines. They deliver consistent and accurate sensor signals so human drivers will be able to rely more fully on assistance systems.

Pressure compensation seals ensure reliable pressure equalization in housings and can be applied in space-saving ways.

Antennas for connected driving

Trouble-free communication between vehicles must be ensured for road safety and convenience. This requires antennas for new communication standards such as 5G. Like the film heaters, powerful antennas also can be produced with printed electronics technology.

Radio frequency identification (RFID) technology optimizes tracking and monitoring of safety-related components. Special-purpose RFID labels can also support connectivity with traffic infrastructure, permitting vehicles to enter restricted areas or to display vacant spaces in parking garages. The latter enables convenient and reliable parking facility management.

Infallible sensor technology is a mission-critical aspect of bringing autonomous driving from concept to reality. Ancillary components such as pressure compensation seals, film heaters, and next-generation antennas will play a vital role in bringing this promise to fruition.

Schreiner ProTech

About the author: Thomas Köberlein is president of Schreiner ProTech, a business unit of Schreiner Group. He can be reached at