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Driveline control is a challenging area. With traditional fuel metering systems, driveline oscillations may follow load disturbances or changes in accelerator position. This problem, emphasized with increased engine power, together with overall increased performance demands leads to a need for more advanced driveline control. The main contribution of the paper is a strategy for fuel metering with active handling of driveline resonances, reducing wheel speed oscillations. Experiments and modeling using a 6x2 heavy truck lead to a linear model capturing the significant torsional resonances in the driveline. A formulation tractable for analysis, design, and implementation is developed. Field trials show that the engine can be controlled to reduce low frequency driveline oscillations, also when facing engine torque restrictions due to diesel smoke reduction. The system thus improves both performance and driveability.

By using engine controlled gear shifting, a manual transmission can be automated without using the clutch during the shift event. The main contribution of this paper is a novel extension of the existing system using active handling of driveline resonances. The strategy is based on a model of the transmission torque, which is derived by using experimental data from a heavy truck. A key step is the design of a criterion for a controller that drives the transmission torque to zero with damped resonances and with a control signal realizable by the engine. The proposed solution offers a possibility to optimize the time needed for a gear shift, which is important since the vehicle is free rolling when in gear-shift condition. Furthermore, neutral gear can successfully be engaged also when facing initial driveline oscillations and load disturbances.