Millions of Steps Across

Össur ensures the quality of its high-tech prosthetics with coordinate measuring machines from ZEISS.

Icelandic company Össur would like to enable people who are missing a limb to live without limitations. Therefore, the prosthetics developed and manufactured in Reykjavik are true high-tech products. To ensure the perfect interaction of the numerous components, Össur uses measuring machines from ZEISS.

Challenge: demanding geometries

A prosthetic leg carries its wearer one million steps every year. To ensure that this is not only possible, but also comfortable, the generally small and light components of the prosthetics must be very strong. This also makes the tolerances very tight: just 10 micrometers for some of the components of computer-controlled knees. Quality Assurance requires precise measuring tools to ensure compliance with the strict specifications. These instruments must also be able to correctly display complex geometries. The artificial knees, for example, feature concave and convex surfaces and cannot be correctly measured manually.

Solution: two coordinate measuring machines

For random sampling measurements, Össur relies on two measuring machines from ZEISS: the ZEISS CONTURA coordinate measuring machine and the ZEISS O-INSPECT multisensor measuring machine. "When all machine tools are running in production, we use them to measure at least 17 different parts every hour," says Ásgeir Páll Gústafsson, Quality Manager and expert in coordinate measuring machines at Össur. The measuring technicians prepare the measurement programs and clamping devices so that their colleagues can position their workpieces properly on the coordinate measuring machine and select the corresponding measuring program. The sensor then automatically scans the workpiece and determines the defined form and location data. Össur has drastically reduced the number of measurements with manual measuring equipment since the acquisition of its first coordinate measuring machine in 2004.

Benefit: production and measurement of complex components

Complex knee components with curved surfaces that Össur had to purchase for a long time are now made by the company. Furthermore, employees had to invest a considerable amount of time for the manual measurements. Moreover, ZEISS PiWeb analysis software that has been in use since 2013 has simplified more than just documentation. Trends in data sequences can be quickly recognized and visualized, enabling employees to quickly draw conclusions about machining processes. The insights provided by the measurement data thus also contribute to the improved quality of the final product. It is this quality that helps Össur's customers stand on two legs. "Just because you lose a leg, doesn't mean you have to stop living," says Gústafsson. "This is what we strive for."

About the company

Össur Kristinsson, a young man from Iceland, was dissatisfied with his cumbersome artificial leg and wanted a better solution. He opened a small workshop in Reykjavik in 1971 and quickly invented the silicon liner, a new type of connection between the body and prosthetic, that is now known around the world. In the space of just two decades, the tiny workshop became a global player listed on the Copenhagen stock exchange and with a current workforce of 2,3000 people In Reykjavik and 17 other sites all over the world, it develops, produces and distributes prosthetics and other orthopedic products for people suffering from arthrosis or injuries.