multitronic

Multitronic is a stepless transmission launched by AUDI AG in late 1999, jointly developed and manufactured by LuK. The capitalization used is multitronic (spelled by Audi with a lower-case leading 'm') and is a registered trademark of AUDI AG.

It is based on the principles of a continuously variable transmission (CVT) popularised by DAF, but differs from other CVTs by using an unconventional type of steel chain consisting of parallel flat chain segments. Unlike the conventional CVT push belt, the Multitronic chain uses tension to transfer forces.

Multitronic is a term originally coined in the original series of Star Trek (see season two, episode 24: The Ultimate Computer).

It offers a stepless automatic transmission in which the ratio between the input shaft and output shaft can be varied continuously within a given range, providing virtually an infinite number of possible ratios. The Multitronic system uses a link-plate chain drive, an oil-cooled multi-plate clutch (initially of six parts, later of seven to enable it to cope better with the high torque outputs of larger turbodiesel engines), and complex electronics, to overcome the traditional shortcomings of CVTs, and allow a CVT transmission to be paired with a more powerful engine.