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This paper presented an engineering review on the state of the art in the research and development of vehicle-trailer handling dynamics and stability controls. The issues and potential technical solutions were identified in various areas and the unique characteristics of vehicle-trailer as a combined system were investigated and compared to a single-unit vehicle system. Many approaches taken in modeling, analysis, simulation and testing were examined, and various control methods, actuations and control implementations were evaluated. As a result of this study, further research areas were also identified. While it is important to maintain the stability of a trailer, thus the stability of a vehicle-trailer combination, it remains one of the major challenges in designing an appropriate control law to balance effectively the requirements between stability and handling performance, which often set conflicting objectives.

This paper presents a visual simulation method for vehicle ride comfort evaluation. First, a 3D vehicle virtual prototyping model is built using ADAMS. With totally 596 degrees of freedom, this model incorporates every major factor that influences the vehicle ride comfort. Based on the virtual model, time domain simulations on random road inputs are further carried out and the vehicle dynamic characteristic parameters are obtained. Then, referencing a real proving ground, a ride comfort testing graphics database that contains road surfaces, rivers, grass, houses, trees, cordilleras and so on, is developed. After setting and programming resources such as graphic frame buffer, channel, scene, light, camera facility, a virtual proving ground that is able to simulate the real world, real color, and light is established. Finally, OpenGVS SDK program tool is used to call virtual proving ground and vehicle model database.

For stability control on a vehicle-trailer combination, the coupling between vehicle and trailer as two pivoted rigid bodies has been investigated, in view of concerns that the coupling strength varies as vehicle-trailer parameters change, and thus plays an important role in the design and robustness of the stability controller. Analyses through root locus and time-domain response have been conducted and several observations have been made, which are valuable for the controller design. A preliminary stability controller with state feedback has been designed and simulated to further verify the studies above.

Dynamic behavior of a partly-filled liquid cargo vehicle subject to simultaneous application of cornering and braking maneuvers is investigated through computer simulation. A three-dimensional quasi-dynamic model of a partly-filled tank of circular cross-section is developed and integrated into a comprehensive three-dimensional model of an articulated vehicle to study its directional response under varying steering and braking inputs, fill volumes and road surface friction. The liquid load movement encountered under combined steering and braking is expressed in terms of variations in the instantaneous c.g. coordinates and mass moments of inertia of the liquid bulk, assuming negligible influence of fundamental slosh frequency and viscous effects.

A generic tank cross-section is formulated to describe the geometry of currently used tanks in transportation of fuel oils and bulk liquids, and to explore optimal tank geometry for enhancement of roll stability limit of tank vehicle combinations. The tank periphery, composed of 8 circular arcs symmetric about the vertical axis, allows more design flexibility in view of the roll stability limits than the conventional tank shapes. A shape optimization problem is formulated to minimize the overturning moment imposed on the vehicle due to c.g. height of the liquid load, and the lateral and vertical movement of the liquid bulk within the partly filled tank. Different optimal tank cross-sections are proposed corresponding to varying fill conditions, while the total cross-sectional area, overall height and overall width are constrained to specified values.