26 Meters of Flex!

Estimated reading time: 3 minutes

Barry Matties spoke with Philip Johnston, managing director of Trackwise Designs, about the company’s patented length-unlimited multilayer printed circuits aimed at replacing conventional wire harnesses. Originally created for the aerospace industry, Trackwise has since seen growing interest from a number of different industries. Jake Kelly, managing director and chairman of Viking Test Ltd., also joined the conversation to discuss the importance of having a flexible equipment supplier when dealing with such a unique technology.

Barry Matties: For our readers, can you give us an overview of Trackwise Designs?

Philip Johnston: Trackwise Designs was formed in May 1989. We just celebrated our first 30 years this month. It was started as a PCB design bureau, hence the name. Soon after, we moved into manufacturing, and in the mid-1990s, we were asked to make a nine-foot-long PCB, which was one of the early mobile phone base station antennas. The company developed a means of making long PCBs, and that was originally the main USP.

Now, as the frequency of the mobile telephony has gone up, by the laws of physics, the size of the circuits has come down. Our original USP has morphed into the manufacturing of antennas using printed circuit technology, and we export these all over the world—about 70% of our product goes to export. We’ve retained our large format manufacturing capability, which is still needed for some niche applications like aircraft guidance radars and long, linear scales for silicon chip manufacturing machines. A few years ago, a large U.K. aerospace engine manufacturer came to Trackwise and said they were looking to replace the wire harness inside of their aerospace engine with flexible PCBs to save weight and space. And because aerospace engines are big, these PCBs were going to be big. They knew that we manufactured these big boards, so they came to see us.

One of the requirements was that the roughly eight-meter-long run should be manufactured as a single piece rather than a daisy chain of interconnected sections. The rest of the world’s manufacturing communities said, “No, that can’t be done.” We had to think about it, and we came up with a means of making length-unlimited multilayer flexible printed circuits. That was the innovation that we first produced a proof of concept sample for and have continued to develop. This patented technology, which we call Improved Harness Technology™, has been granted in the U.K., the U.S., and China, and is in the process of being granted in the EU, Brazil, and Canada—all of the main airframe manufacturing locations. The technology has been focused on the aerospace industry primarily because of its ability to save weight and space.

This is not a new technology. Flex PCBs have been around for the best part of 100 years, and the reason we can get a cellphone in your top pocket is that all of the wire inside has been replaced by flexible printed circuits. It’s now a multibillion-dollar worldwide industry usually used inside of a phone, laptop, or an avionics box. Trackwise is now able to offer box-to-box wiring, so those proven benefits of weight, space, reliability, and precision can now be achieved at the fuselage or wing level instead of just inside of a box.

Our original approach/intent was for the aerospace industry, but I think we are seeing an interesting macrotrend. In all industries—including industrial, aerospace, automotive, and medical—everybody wants more functionality into either the same or less weight or space. If you are trying to do that with wires, it’s impossible.

A large business jet manufacturer has been in touch with Trackwise too. They’ve given us an analysis that shows that the wire content in their business jets is increasing by 25% every five years because more and more functionality is desired. Operators want to fly jets with this greater functionality with as many passengers as they can; therefore, the issues of reducing harness weight and space are becoming ever more significant. As I said earlier, we are seeing tremendous demand from across the industrial spectrum for this new technology, and we’re all about length-unlimited multilayer flexible printed circuits.

Matties: A single- or double-sided length-unlimited PCB might be simple, but when you start adding in multilayer, that sounds like quite a challenge.

Johnston: The longest we’ve made to date is 26 meters long with shielded power cables. The challenges have been many and varied. One of the challenges is to find equipment and machining manufacturers willing and able to modify their equipment for the particular needs of making length-unlimited. Viking Test Ltd. has been a big part of that journey for Trackwise.

To read this entire article, which appeared in the July 2019 issue of Design007 Magazine, click here.