Continuously variable transmissions (CVT) in connection with driveline management gain more and more in importance for modern agricultural tractors. They allow reduced fuel consumption and increased productivity by dynamically optimising the operating points of engine and transmission according to the chosen control strategy (e.g. maximum drawbar pull, lowest fuel consumption, constant engine rpm) and an improvement of the working process by means of possible automation and relief of the driver. Furthermore maximum driving comfort and ease of use are achieved on the road as well as on the field.

Usually tractor CVTs are designed as mechanic-hydraulic power split transmissions; diesel-electric propulsion systems are also seriously taken into consideration to meet the requirements of efficiency, pollution issues, transmission-ratio spread, and power capacity as well as allowing for special features like geared neutral and fast reversing.

If the driveline encloses two CVT units, the engine torque can be distributed individually to the wheels, disclosing many interesting possibilities. A modern, flexible driveline for AWD vehicles can be realized, which, in connection with an intelligent control strategy, will offer great potential in terms of traction, flexibility, efficiency and intransigent on-road/off-road capability.

Together with a partner in the industry, a system like that shall be developed and evaluated at the FTM, working group mobile off-road machinery. Possible structures and control strategies will be simulated and analysed. Especially the tuning of the gear ratios according to the traction situation is a special challenge here.