A salute to " Star Trek " : Audi created a walkable " holodeck " that allows engineers to assess virtually the design of new models at an early stage. Working with supplier Mahle and industrial machine maker Trumpf, Porsche used 3D-printing technology to create pistons for the high-performance engine of the 911 GT2 RS. Below, a laser beam heats and melts metal powder as the piston is formed. march 2021 * shift 25