Martin Stein has studied mathematics and physics at Leibniz University Hanover, Germany, and finished his Ph.D. in 2012. He’s been heading the working group for gear and thread metrology at Physikalisch-Technische Bundesanstalt (PTB) since 2014. One of that group’s main research areas is metrology for large gears as used in wind energy systems. Martin Stein is an active member in national standardization bodies for gear metrology of the VDI/VDE and DIN. He is a lecturer at TU Braunschweig for the MSc course on Metrology and Measurement Technology.