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One of the most important vibration isolators in vehicles is the powertrain mounting system (PMS). It transmits the powertrain vibrations to the body, and the chassis vibrations excited by road to the powertrain. The design of a PMS is an essential part in vehicle safety and in improving the vehicle noise, vibration and harshness (NVH) performances. Many organizations are increasingly relying on design simulation rather than trail-and-error based experiments which are expensive and time-consuming for PMS evaluation. However, design parameters for PMS are always uncertain in actual cases due to tolerances in manufacturing and assembly processes. In this paper, based on a front wheel drive vehicle with a transversely four-cylinder engine, the uncertain characteristics of PMS are studied by interval analysis method.

Connected and automated vehicles (CAVs) can improve traffic efficiency and reduce fuel consumption. This paper proposes a cooperative game approach to merging sequence and optimal trajectory planning of CAVs at unsignalized intersections. The trajectory of the vehicles in the control zone is optimized by the Pontryagin minimum principle. The vehicle's travel time, fuel consumption, and passenger comfort are considered to construct the joint cost function, completing the optimal trajectory planning to minimize the joint cost function. Analyzing the different states between neighboring CAVs at the intersection to calculate the minimum safety interval. The cooperative game approach to merging sequence aims to minimize the global cost and the merging sequence of CAVs is dynamically adjusted according to the gaming result. The multi-player games are decomposed into two-player games, to realize the goal of the minimal global cost and improve the calculation efficiency.

In autonomous driving, variations in tire vertical load, tire slip angle, road conditions, tire pressure and tire friction all contribute to uncertainty in tire cornering stiffness. Even the same tire may vary slightly during the manufacturing process. Therefore, the uncertainty of tire cornering stiffness has an important influence for autonomous driving path planning and control strategies. In this paper, the Chebyshev interval method is used to represent the uncertainty of tire cornering stiffness and is combined with a model predictive control algorithm to obtain the trajectory interval bands under local path planning and tracking control. The accuracy of the tire cornering stiffness model and the path tracking efficiency are verified by comparing with the path planning and control results without considering the corner stiffness uncertainties.

Increased focus on vehicle comfort and ride has led the automotive industry to look into low vibration, noise and hardness alternative designs for powertrain system components. In this paper, the vibration theory and dynamic vibration absorber (DVA) theory is presented. The modal analysis of propeller shaft assembly has been accomplished. Based on dynamic vibration absorber principle, performance parameters of dynamic vibration absorber are matched and structure is also designed. LMS equipment is applied to verify the natural frequency of absorber samples. The matching of stiffness and damping of DVA is presented. The dynamic response of drive shaft system based on the mass ratio of DVA is researched in this paper. Results from simulations and tests indicates that the amplitude of propeller shaft resonance can be effectively reduced by attaching a DVA to the long propeller shaft.