“Technical knowledge wasn’t enough, I needed to see the big picture”

Trumpf is one of Germany’s hidden champions. Even though it’s not a household name, the company builds high-tech machines for clients all over the world, employing more than 16,000 people. Key to the group’s success is that since its founding in 1923, it’s been family-owned. “We work on innovations where we might have to wait five to ten years before we see a return on investment,” says Sebastian Pricking. “If your company is listed on the stock market, looking that far ahead isn’t always possible.”

Pricking’s team works in Trumpf’s laser development department, on solid-state lasers. These include YAG-based disks but also lasers where the active medium is an optical fiber. “We do basic research,” he explains. “While colleagues specialize in the CAD designs and the software, my team takes care of the system interfaces, the fundamental principles and the basic concepts. When designing the optical layout of a new laser, for example, we decide which kinds of mirrors to use, the coatings on the lenses, and so on, based on simulations and lab experiments. The actual mechanical integration is done by another team.”

New features

Typically, Trumpf’s lasers are used in industry to treat metals. “Welding and cutting are some of the main applications,” illustrates Pricking. “One of the biggest industries we serve is automotive. Electomobility in particular is driving growth here. The construction of batteries and electro-motors requires a lot of laser processes. That market is growing significantly now.”

Lasers have been used for a while in those applications, but that doesn’t mean there isn’t more technological development to do. “Parameters like power and beam quality are still improving,” Pricking points out. “We’re also focusing on new features. For example, we develop pulsed lasers. Here, the light isn’t continuous but comes in pulses with a higher peak power. That means that we need to time the pulses exactly right for the customer’s application.”

“We’re definitely capable of offering suitable power levels for all the standard processes,” Pricking says. “Solid-state lasers provide a broad range of power levels with an excellent wall-plug efficiency. One of our designs is a disk laser, which offers up to 24 kilowatts of infrared laser light.”

A disk laser has a thin active medium, which is placed on top of a heat sink. This solves issues around cooling. “In the past, the active medium was often shaped like a rod,” Pricking recalls. “But that caused problems with the cooling because it’s harder to apply proper cooling to get the heat away. There are two possible solutions to this. Either you take the rod and press it into a disk shape, so the heat escapes more easily due to the increased surface. Or you take it and pull it so that it becomes a fiber-based laser. We offer both of these designs to customers.”

Right track

Pricking currently heads a team that’s designing a new fiber-based laser. He only recently took on this position. It prompted him to follow the “Systems architect(ing)” course at High Tech Institute.

“I’m originally an experimental physicist,” says Pricking. “I can do the lab work, I can simulate and calculate all the necessary effects. But when I took over the team, my work changed. I had to collect the requirements from the stakeholders. I had to make chains of tolerances. I had all these interfaces I had to organize. I had to make sure everything fit together. I needed to be a system architect. The issue wasn’t the technical aspects of the job but how to organize the design. This course gave me the tools and the framework that allowed me to see the big picture and make sure I hadn’t forgotten anything. The framework showed me where I was on the right track and where something was missing. It allowed me to close the gaps.”

Among other things, the course taught Pricking how to apply the CAFCR framework. “It allowed me to orient myself. I assume there are other, competing, frameworks, but this one fits our way of working nicely. It confirmed we were on the right track.”

Besides the content, Pricking also liked the way the course was taught. “I liked the mix between the experimental and group work, where you present the group’s results to solve a given challenge, for example, and the theoretical presentations about the model and how it works. The week was filled quite nicely. The whole thing was very entertaining. At the evening dinners, I had the opportunity to exchange experiences with the other students on how they do things in their companies.”

During the course, the teaching team was very responsive to questions from the students. “I asked which software can be used to apply the framework,” Pricking gives an example. “The teacher mentioned that it wasn’t part of the course, but he still offered me a list of software tools we could use, together with the advantages and disadvantages of each.”

Pricking is now applying the lessons learned in his daily practice. “With this new background, I checked everything again. I applied the model to the project. I saw that there were a few gaps, which we closed rapidly. This course helped us improve our laser concept. Our next project will use the framework from the start, for sure.”

This article was written in close collaboration with High Tech Institute. Main picture credit: André Boden/Trumpf