A direct-shift gearbox (German: Direkt-Schalt-Getriebe), commonly abbreviated to DSG, is an electronically controlled dual-clutch multiple-shaft manual gearbox, in a transaxle design – without a conventional clutch pedal, and with full automatic, or semi-manual control. The controller for the clutching functionality is housed in the Mechatronic Unit.
The clutches and gearbox units in the DSG are operated hydraulically. This function is performed by the gearbox mechatronics module, housed in the DSG. The term “mechatronics” is derived from combining the words “mechanics” and “electronics”. And this is exactly how the mechatronics module is structured with the electronic transmission control unit, various sensors and the hydraulic control unit all forming one compact entity.