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Based on a half-vehicle model, an algorithm is proposed for a Kalman filter optimal active vehicle suspension system using the correlation between front and rear wheel road inputs. In this paper, two main issues were investigated, i.e. the estimation accuracy of the Kalman filter for state variables, and the potential improvements from wheelbase preview. Simulations showed good estimations from the state observer. However, if the wheelbase preview algorithm is incorporated, the estimation accuracy for the additional states significantly decreases as vehicle speed and the corresponding measurement noises increase. Significant benefits from wheelbase preview were further proved, and the available performance improvements of the rear wheel station could be up to 35 per cent. Because of the feasibility and effectiveness of the proposed algorithm, and no additional cost for measurements and sensing needs, wheelbase preview can be a promising algorithm for Kalman filter active suspension system designs.

A non-linear dynamic model of the passenger car driveline with dual-clutch transmission is proposed by treating the dry dual clutch as a system of multiple rigid bodies for numerical simulation of their engaging behaviours in launch phases. For the synthetic optimal engaging performance and simple optimization procedures, the effects of the friction work, shock intensity, and engine torque are examined and introduced into the objective function. The optimal engagement laws are deduced for the dry dual clutch by finding a compromise between the friction work, shock intensity, and engine torque, based upon the extremum value theorem. Numerical examples are given using the present mathematical modelling for the purpose of comparison of the transient dynamic responses of the dual clutch during engagement in a number of typical working conditions. It is shown that the present control strategy is efficient and promising.

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Theoretical and experimental analyses of torsional vibrations and acoustic noise for a deep hybrid electric vehicle driveline including an electric, continuously variable transmission are carried out. The dynamic and mathematical models with 16 degrees of freedom in a matrix form are developed for the torsional vibration characteristics of the hybrid driveline. On the other hand, the noise sources of the hybrid electric vehicle powertrain excited in the pure electric mode and the hybrid drive mode are tested and measured using acoustic and speed sensors. The noise orders and the frequency domain responses are constructed using signal treatment and torsional vibration analysis. The theoretical predictions for the natural frequencies and the corresponding vibration modes of the hybrid driveline are presented. The noise test results are also given in accordance with the torsional vibration modes of the hybrid driveline in the pure electric mode and the hybrid drive mode. The noise sources due to the self-excited and frequency-multiplied vibrations are found, focusing on the compound planetary gear set in the power-split electric, continuously variable transmission.