A unique optical tribometer combining two different measurement methods was created by experts from the Faculty of Mechanical Engineering in Brno. The contract was procured by a Japanese lubricant development company. No commercial supplier is able to produce a similar device. This was the third such contract for the Brno scientists, who have previously produced customised equipment for a large Japanese car company and a German university.

A tribometer is, in layman’s terms, a device designed to measure friction and wear between two surfaces. A Japanese company that develops grease lubricants was looking for a specially adapted one. They were unsuccessful on the market, so they turned to scientists from the BUT to build the necessary technology tailored to their needs.

“Our field of tribology is quite narrowly focused. Unlike in Life Sciences, where commercial equipment is available in large quantities and its level is close to the cutting edge of current science, in our field there is a bigger gap between what equipment can be bought commercially and what methods and equipment are used by scientific workplaces,” explains Petr Šperka from the Institute of Machine and Industrial Design at the Faculty of Mechanical Engineering BUT. In other words: if a company wants something extra, it has to have the device made to order.

To develop greases, the Japanese needed a device that could measure friction and wear, but they also wanted to know what was happening to the individual components of the grease and how the process was evolving over time. "A conventional tribometer measures friction and lubrication film thickness, which is of course important. However, a grease is composed of at least two components, each of which has a specific role. Using optical methods, we are able to see what one component and the other can do at and around the point of contact. We can separately visualise, quantify and observe them. For this purpose, we have added another optical method to the device. It was a kind of “two-in-one”, the device contains three cameras in total, one of them high-speed for recording fast events,” explains Šperka, adding that it was the most complex device of this type constructed at the institute so far.

However, this was not the first contract of this kind. In 2016, Brno engineers produced a unique tribometer for a large Japanese car company, and two years later another specific device went to a German university. “You could count the workplaces that could do this on one hand,” says Šperka, who collaborated with his colleagues on the development.

The development of customised equipment always starts with the specification of customer requirements. According to them, scientists design certain components and price the device in development. This is followed by the design of the structure and the production itself. “We buy some of the parts ready-made, such as the microscope and cameras. It is then our task to combine everything into a functional whole; the value lies in the interconnection, our experience and the guarantee that the device will do what we need it to do,” adds Šperka.

The optical tribometer took the researchers several months to develop and has been used in Japan for research and development of lubricants since March. “What I enjoy most is that our work is about solving a specific problem, in this case a technical and structural problem. You are basically building a prototype, but it has to work well,” concludes Šperka.