Could 3-D printers undo decades of frame-up circuit board assembly?
Ever since Henry Ford invented the assembly line, automobiles were assembled by first taking a frame, or chassis, and pulling it down a long line while workers bolted pieces and parts onto it until at the end – voilà! – you had an automobile.
So successful and cost-effective was the assembly line concept that virtually everything from that point forward was built – assembled – that way. And thus our modern day paradigm for manufacturing was established.
In the 1960s a bunch of bright automotive engineers had an idea that they thought would be better. What if you did away with the frame, or chassis, and instead fabricated larger, integrated subassemblies and pulled them along the assembly line? Fewer parts; less weight; faster, and (allegedly) better manufacturing. Thus Chrysler introduced the “unibody” (unit-body construction) design for automobiles. Chrysler, the company with the oldest product offering, worst financial shape, and the scrappiest management, led by Lee Iacocca, eventually did away with the chassis in favor of an integrated unibody construction on all its cars.
Today, almost all motor vehicles, including many trucks and most SUVs, are built without the frame-up design that Henry Ford established. It took longer than those sharp engineers of the ’60s imagined, but the paradigm has shifted, and today building product via bolting parts onto a chassis is long behind us – at least in the automobile industry.
But in many other industries, including high-technology electronics, product is still manufactured based on the frame-up concept from the early 1900s. In our case the chassis is a circuit board, which is then pulled through a surface mount line with components glued, soldered or screwed on until – voilà! – you have an end-product.
Now, I make printed circuit boards so I kind of like this concept. However …
Recently I was visiting a college engineering department and saw what I believe may be the game-changing, paradigm-altering combination that will significantly and permanently alter our industry.
In a large room in the mechanical engineering area sat a 3-D printer. These are really neat inventions that can transform plastics and even metals into finished parts by taking CAD data and directly “printing” a finished three-dimensional part to specified tolerances. Really cool stuff for making mechanical parts. Some sharp young engineers were working on robotic “enhancements” to the machine “center.” Their concept was, “what if” you put an inkjet print head on a robot and “print” electro-conductive ink on the “3-D printed” part? The concept (actually samples) had circuitry on the “printed” part so they could use the intricate mechanical part as a three-dimensional circuit board, thus reducing the number of traditional boards necessary to make the end-product work. In short, do away with the “chassis” (aka the PCB) and turn the product into an electronic circuit. The goal: to reduce weight, size and costs, not unlike how the unibody automobile changed the paradigm in the automobile industry.
There are other interesting similarities. The only way that automobiles could eliminate the chassis was when raw materials, such as steel, aluminum or plastics, became sufficiently strong and light so that body sheet metal could structurally handle parts being connected to it. Equally, assembly techniques had progressed to a point where robots could spot weld efficiently, reducing the number of screws, bolts and weighty fasteners.
The 3-D printer has enabled parts to be created with new composite materials. Equally, the robotic processes now available access tighter spots with greater precision to perform tasks not possible before. Newer material options combined with more precise robotics are potentially enabling a mechanical printing process to replace an electronic, ground-up assembly process.
In Detroit during the 1970s most people were focused on other engineering feats. Safer bumpers, air bags, fuel-efficient engines, etc., were where the consumer and media buzz was. However, it was the behind-the-scenes activities that resulted in a real paradigm shift that enabled greater safety and efficiency. Maybe today, in our industry, we should be paying more attention to some of the bright mechanical engineers in our colleges and universities who are rethinking the basic paradigm. As an industry, the buzz often seems to revolve around things like printed electronics, embedded components, ever smaller vias – enhancements to the existing paradigm of fabricating a panel and then adding parts to create an end-product. However, behind the scenes lie some bright engineers asking why we even need a circuit board at all when we can deposit electro-conductive inks, pastes and chips on “printed” mechanical parts to significantly eliminate size, weight and cost.
Will it take this generation of bright engineers 40 years to change our industry’s paradigm, as it did the guys in Detroit back in the ’70s? I doubt it! The pace of change has accelerated, and tools are more impressive today than way back when. But I do know that the “big” change will come when and from where we all least expect it. And in many ways history does repeat itself; the kids who ask “what if?” without being tethered to the status quo find the answers that change industries and people’s lives.