Q&A: Print Your Next Wiring Harness
Imagine your next-generation vehicle wiring harness printed in electrically-conductive ink on a thin, stretchable and flexible substrate with sensors embedded into the molded substrate. Known as flexible hybrid electronics (FHE), this technology uses a combination of high-precision printing technology and advanced electronics. The result is lightweight, package-efficient and physically flexible circuitry, first used by Ford on a limited trial basis in the overhead console of the 2013 Fusion.
“FHE is basically printing the circuits on a large roll of film,” explained Dan Lawrence, program manager at the IQM Research Institute, an advanced-technology incubator that is promoting FHE within multiple industry sectors. He noted that FHE can be “incorporated into any substrate—an injection-molded door inner panel or the physical structure of the vehicle.” Headliners, the centerstack HMI, the roof panel incorporating photovoltaics and RFID antenna, to name a few applications.
Automotive Engineering spoke with Lawrence at IQM’s Ann Arbor, MI, offices.
Was the impetus behind FHE vehicle electrification, connected car and autonomy trends?
Yes, all of them. Because it allows you to do things that incumbent harness technology can’t. And every kilogram you can shave off a car has tangible fuel economy benefits. The military land-vehicle systems folks at U.S. Army TARDEC and the commercial-appliances sectors are also interested. We’re working with companies across the industry. It’s up to them to take those learnings and apply them to their own projects for commercialization.
We’re not looking at vehicle programs 15 years down the road—we’re looking at the next 2 to 5 years. FHE is a platform that’s basically ready now. We’re also looking to add some laboratory and demonstration capability to this area as well including prototyping and small-scale batches of actual products. We’re (IQM) here to evangelize and collect the industry’s wants and needs and show what’s possible so that the designers, engineers, purchasing departments can say, ‘Hey, this has value, let’s bring this technology forward.’
The technology would be a disruptor to incumbent harness technologies supplied by the Yazakis and Delphis of the world, yes?
FHE can be a distruptive technology because the wire harness manufacturer, the headliner manufacturer and whomever else is in the supply chain up to the OEMs, in the sense that it has potential to add value. If you’re only making headliners, FHE offers the chance to make them far more functional. We’re not here to steal anyone’s business; we’re here to help them grow.
How does FHE incorporate electronics hardware such as circuit boards?
Circuit boards will remain with us for the forseeable future but in terms of manufacturing they’re rate-limited by pick-and-place machines. FHE is basically printing the circuits off a large roll of film. My background’s in the printing industry—it’s amazing how fast and in what large volumes the product comes off the press. Being physically flexible in and of itself is not really the selling point—it’s where you can put that flexibility, including package and manufacturing flexibility. A key benefit is we can make hundreds of thousands and also do customized ones. We use high-speed production and a change of printing plates won’t break the bank.
You can use an entire door panel as electronics, for example. You can’t do that with a printed circuit board. Or for any user interface for example. On an appliance control panel, if you have a hard circuit board and have your switches populated and your lighting populated, it starts to get pretty expensive. We’ll probably still need some microcontrollers depending on the design rules but going forward we’ll need less and less of them.
Does the ink contain a magnetic constituent?
You can have magnetized ink for a coil and dialectric ink for a capacitor and semi-conducting ink for a transistor. If you disassembled your laptop and looked at its board, a decent amount of the content can be replicated with the printing process.