Today’s and tomorrow’s feature-rich, highly automated vehicles require a lot of inputs and outputs — for every sensor, actuator, peripheral and display — and they all need their own cables and connectors. OEMs continue to add capabilities that lead to more inputs and outputs, such as radars, cameras, infotainment screens and temperature sensors, to name just a few. But space is limited for cables within a vehicle and for terminations on circuit boards.
Using a zonal architecture helps cut down the total cabling within a vehicle, because connections are consolidated at zone controllers onto power and data backbones. However, that approach leads to dense connections at the zone controllers.
While wireless connections are prevalent among consumer devices, in automotive they are limited to niche applications. Dedicated cables and connectors remain the most cost-effective approach to supporting required functionality for the vast and growing majority of devices, despite the space constraints.
One way to address this crunch is miniaturizing the connectors and shrinking the wire gauges to achieve higher density. Connector sizes are trending toward 0.50mm, down from 1.5mm back in the 1980s when vehicle electronics began to gain momentum. Connectors of this size can accommodate cables ranging from 0.35mm2 to as small as 0.13mm2 and maintain high performance for electrical signaling. Almost anything that needs signaling can use miniaturized connectors, from cameras requiring high bandwidth to turn indicators requiring very little. Even low-power connections can be miniaturized to a point, as long as the gauge can sustain the required current.
Miniaturized connectors present several challenges in automotive — the greatest of which is that they are too small for humans to assemble. Getting such precision demands capital investment in the automation equipment that is needed to cut, strip and terminate bulk cabling. Automated plugging of connectors during vehicle assembly might also be necessary.
Ensuring that the automation equipment is able to handle miniaturized connectors effectively requires crafting the connectors and cables so that they work well with the automation. For example, a twisted-pair cable is oval rather than round, so it has to be properly orientated to get the stripping and trimming right on the shielding. The automated system requires either an optical capability, so that it can see how the oval is oriented, or some kind of mechanical stop in the shielding to signal to the system that the orientation is correct.
Constructing the cabling and connectors to work well with automation — and with each other — is essential to successfully using miniaturization. Cable engineering must collaborate with connector engineering, and design teams must work in lockstep with manufacturing teams to unite product development with process development so that everything is created with automation techniques in mind.
Planning for the future
Another challenge with miniaturization is fragility, so designers have to take into account how the components will be handled and how they should be protected from harm before final assembly. If a miniaturized male connector has terminals that protrude 12mm, for example, it would not take much force to bend the terminals. In that case, a retractable male blade stabilizer might be necessary. The plate of the stabilizer protects the terminals, sliding out of the way when the male connector mates with a female connector.
Other industries, such as IT and telecom, have pioneered the use of miniaturized connectors, and indeed they implement terminals that are even smaller, at 0.40mm. As requirements for denser connections continue to increase, the automotive industry might take a closer look at such smaller sizes down the road.
Aptiv is at the forefront of developing robust connectors that meet the requirements of today’s and tomorrow’s hyperconnected vehicles. We have a comprehensive and unique view of electrical/electronic architectures — as the only provider of both the vehicle “brain,” or compute, and the “nervous system” for power and data distribution. Further, as one of the only suppliers of both connection systems and wiring harnesses, we have a unique perspective on how best to tackle the challenges with miniaturization and automation while optimizing performance and cost. This larger context will continue to increase in importance as the industry evolves.