Illuminating the Path to a Software-Defined Future

Matthaeus Artmann, Project Manager Advanced Systems & Technologies, ZKW

Through this article, Matthaeus Artmann, Technology Manager Advanced Technologies at ZKW, shares his insights on the evolving landscape of exterior automotive lighting. He discusses the transition to LED-based lighting, the challenges of thermal management and the advancements in LED technology. Artmann highlights the importance of integrating high-power drivers and high-bandwidth interfaces to overcome current limitations and the shift towards centralized architectures for software-defined vehicles. He emphasizes the need for automotive suppliers to innovate and collaborate with OEMs to ensure a smooth transition and enhance the functionality and sustainability of exterior lighting systems.

Looking at the automotive industry for exterior lighting, it is clear, that light-emitting diodes (LED) have become the main photonic element utilized for all known applications, no matter if it's for road illumination or signalling.

More than a decade ago, LEDs started to succeed in well-established light sources such as halogen bulbs and HID lamps. LASER was in vogue for a while, but over time became only a niche technology for very specific use cases in exterior lighting. ZKW played an important role in bringing the first full-LED-equipped headlamp and also in developing a LASER-based application.

With this big shift to LEDs, some challenges occurred down the road which are still valid nowadays in my opinion. Technology-wise, it was clear from the beginning that LEDs need specific thermal management to optimize lifetime since a headlamp comprises a very harsh environment with high-temperature conditions causing degradation to semiconductors.

Thermal solutions now look very similar to those from the early beginnings, like FR4-based PCBs on heatsinks with a cooling fan on the back, but advancements like insulated metal substrate (IMS) and copper inlays brought greater flexibility. I see movements that the materials used could change as a matter of sustainability and environmental health requirements, but not soon.

Changing to new materials seems tempting but in my humble opinion needs a global approach, as the automotive industry with its very specific requirements on grade and quality has less power to make it happen.

"The transition to LED-based exterior lighting in the automotive industry presents both challenges and opportunities. While advancements in thermal management and miniaturization are ongoing, the integration of high-power drivers and high-bandwidth interfaces, along with a shift towards centralized architectures, will be key to unlocking the full potential of software-defined vehicles."

Function-wise, flexibility scales up with the number of LEDs and their size used as OEMs are demanding it and pushing. Headlamps and rear lamps with several hundreds of tiny LEDs are state-of-the-art, but no one knows or sees them. And the trend goes on, with micrometre-sized LEDs on the horizon for much more flexibility. But this comes at the cost of complex LED drivers and interfaces, as well as weight caused by a lot of wires used.

My observation here is that the introduction of smaller and integrated high-power drivers accompanied by high bandwidth interfaces such as CAN-FD and 10Base-T1S is the key to getting rid of these problems. As usual, costs from a BOM perspective are crucial in the beginning, but this argument could be counterbalanced by the fact, that fewer cables and wires are used which reduces overall weight.

The industry-wide shift to centralized architectures to enable software-defined vehicles (SDV) already affects the design and electrical components for exterior lighting as mentioned before, but more in a second step from my perspective where ADAS, Infotainment and Connectivity are the frontrunning domains.

I see a chance for automotive suppliers such as ZKW among other competitors to already prepare their products in a way, that the transition of exterior lighting to SDV will be smooth. Software has been already an integral part of exterior lighting products, but even if OEMs are claiming software engineering as their sole competence more and more, there are possibilities as OEMs are not immune from failing. The difficulty in my opinion here is to find an open door and be successful and persuade OEMs by bringing added value which they won’t have. Together with our shareholder LG, we are investigating doing so.

Everyone in the automotive industry is talking about greater functionality with software and updates over time—you can see it at related conferences and media news, but everyone should also take care of the hardware needed to realize all the innovative concepts.

My future perspective here would be to come up with an all-in-one package consisting of use cases, added value, software and hardware on one hand and on the other hand, investigate in exploitation of existing products/technologies by adding modern capabilities. I am looking forward with an open mind to all the future opportunities.