Bugatti Veyron transmission technologies revealed by Ricardo at Berlin’s CTI-Symposium

The 7-speed Dual Clutch Transmission (DCT) system developed for the 406km/h, 987bhp Bugatti Veyron sportscar will be shown for the first time by Ricardo at the 4th International CTI-Symposium held in Berlin this week. The twin-clutch gearbox of the Bugatti Veyron combines the dynamic advantages of a manual gearbox with the convenience of an automatic to an as yet unparalleled level of perfection. One significant differentiation criteria compared to the classic automatic gearbox is that no torque converter is used as a moving-off element. Instead, the gearbox has a twin clutch that is composed of two wet-running multi-disc clutches.

Delegates at this prestigious international event, which highlights some of the world’s most innovative automotive transmission technologies, will have a one-off opportunity to see this advanced DCT unit on which Ricardo has collaborated with Bugatti Engineering GmbH in both its development and manufacture. Under the highly confidential arrangements surrounding the technical collaboration between the two companies, this is the only public gathering at which Ricardo will show the specially produced display exhibit.

In addition to the Veyron’s DCT transmission, a range of further technologies will be featured by Ricardo at the symposium’s parallel exhibition, including:

A new version of the Ricardo’s highly successful Torque Vectoring concept that uses conventional actuation technology in conjunction with the company’s patented gear arrangement to achieve unparalleled packaging advantages

The Ricardo shift actuation concept, successfully deployed in the Chrysler ME Four-Twelve sportscar, which will be demonstrated in the form of an actuator test rig showing Ricardo’s patented shift rail selection & actuation system

New transmission CAE simulation technologies; Ricardo experts will be demonstrating the Ricardo Transmission Library soon to be available in the Modelica object-oriented modeling language for use in Dymola dynamic simulation environment, an ideal solution for development of plant models for all automated transmission systems

In addition to the exhibition displays, Ricardo will co-present a paper with Bugatti Engineering GmbH entitled "The 7-speed DSG Transmission and Active Driveline for the Bugatti Veyron - Design, development and Control System".

The twin-clutch gearbox of the Bugatti Veyron combines the dynamic advantages of a manual gearbox with the convenience of an automatic to an as yet unparalleled level of perfection. One significant differentiation criteria compared to the classic automatic gearbox is that no torque converter is used as a moving-off element. Instead, the gearbox has a twin clutch that is composed of two wet-running multi-disc clutches.

The twin-clutch gearbox is arranged longitudinally ahead of the mid engine in the all-wheel drive Bugatti Veyron. The 1001 h.p. 16-cylinder engine itself is located directly ahead of the rear axle. Both the gearbox and the engine are designed as dry sump units – something that is particularly important in terms of achieving a lower centre of gravity. In order to distribute the power between the front and rear axles, Bugatti uses a Haldex transmission unit integrated behind the front-axle differential. The rear-axle differential also features a multi-disc transverse lock.

The DSG of the Bugatti Veyron impresses with its extremely short gearshift times and maximum gearshift comfort. The gearbox is shifted in manual mode using gearshift paddles behind the steering wheel or using a joystick-like lever in the centre console. It goes without saying that, even in fully automatic mode, the exemplary short gearshift times and incomparable gearshift method are still available.

The seven-speed DSG in the Bugatti Veyron represents a new high point for this gearshift technology.