Mild hybrid, plug-in hybrid, battery-electric drive, permanent internet connection, sensor-supported 360-degree environment monitoring, and safety-relevant assistance functions are just a small selection of what is now and soon will be “docking” to automotive on-board networks. On the one hand, this is a great opportunity for drivers, who can now supplement their own personal digital revolution (smartphone) with the benefits of digitization in their cars. On the other hand, it presents a huge challenge for wiring system specialists like us, as we deal with an extreme growth in data traffic and have to map an almost impenetrable variety of functions and variants into the wiring system.
Given the dimensions of this growth, one thing is clear: current wiring systems can’t handle it. This is not simply my personal opinion; it is based on facts. Intedis – a joint venture between wiring system specialist LEONI and electronics specialist Hella – has conducted a study in which 34 wiring system architectures (from real vehicles as well as pre-development projects and concept studies) were thoroughly analyzed in terms of their viability for future use. This study and its results will be virtually presented in detail at the Wiring Systems Conference (Landshut) on September 22, 2020 and the 8th International Conference on Automotive Wire Harness and Electronic Distribution Systems (Ludwigsburg) on September 30, 2020.
Countering complexity with new ideas
The first insight was that approximately half of the wiring systems did not meet future requirements for robust power supply, fault tolerance, and practical functionality. The second insight was that the analyzed architectures can be divided into three categories.
The first category is a minimum-risk approach, using a successive expansion of existing architectures. Because of the enormous need for expansion, this approach will probably end up in “overkill,” as on-board networks become too complex, too expensive, and too heavy.
The second approach involves moderate integration and allocation of functions in larger ECUs. This reduces the number of ECUs and thus the complexity of the wiring system, which seems more practical.
The third approach is more disruptive. It consists of a completely new architecture, with a few large central computers into which most of the functions for data and power distribution are integrated. In addition, smaller zone controllers regulate data traffic and energy management in the vehicle periphery. Such a concept is probably the best way out of the complexity trap.