DETROIT – Whether it’s at work, home or school, everyone wants a data network that is fast, secure and does not cost too much. Powertrain engineers are no different.
And, like a family with slow cable, a couple of high-definition televisions and a growing variety of mobile devices, engineers are growing impatient with the speed of their current data plan.
The number of sensors, electronic controllers and systems that need to communicate under the hood are skyrocketing, but Ethernet-style, high-speed networks used in homes and offices are not yet practical for vehicles, a panel of experts says at the 2013 SAE World Congress here.
Instead, engineers for the most part are hoping today’s conventional CAN (controller area network) data bus electronic architectures can adapt to the growing challenges.
It will not be easy. Sensors create loads of data, and their numbers are soaring as they are used to gather information to control emissions and monitor more engine functions.
The need for sensors grows even higher for diesels with complex exhaust aftertreatment systems and complicated hybrid-electric powertrains, says Dean Tomazic, vice president-Light Duty Powertrain and Vehicle Engineering, FEV.
What’s more, the number of electronic controllers has grown from four or five per vehicle a few years ago to 20 to 40 now, and they all need to talk to one another, says Gregory Weber, director-Powertrain Controls Engineering, Chrysler.
The data issue can be solved with higher-speed data networks that handle faster back-and-forth communication, but these are cost-prohibitive, says David Helton, chief engineer-Gasoline Engine Management Systems, Delphi.
There also are sophisticated high-speed data networks such as the FlexRay system, but it now is used mostly in critical safety related applications.
“Cost dictates what we can do within the powertrain serial data architecture,” Helton says.
In addition to being costly, he says moving from a CAN system to FlexRay represents a big jump in architecture design and strategy. A more feasible near-term solution is a faster version of the conventional CAN protocol called CAN FD, which Helton likens to a turbocharged version of CAN.
Most panelists reluctantly agree that faster data transfer within the vehicle ultimately will be driven by insatiable customer demands for more convenience items, entertainment and connectivity, not powertrain requirements.
