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Heavy vehicles commonly use dual tires on their load and traction axles. As the only vehicle component involved in force transmission to the road, the tire is an important element in the road damage process. In this context, two factors involved are the tire's supported load and inflation pressure. Traditional practical assumptions are that each of the tires in dual arrangement supports the same load, and that the contact patch pressure is very similar to the tire's inflation pressure. To provide data about the load distribution and contact pressure in the tire's contact patch, a lab experimental study was carried out. For that, a lab device was used to determine the static load and pressure in the contact patch, using three different sets of heavy duty radial tires subjected to several combinations of supported load and inflation pressure.

Trucks with semi-trailers are widely used for transportation of goods due their low operation cost, but inherent to these vehicles are some problems such as a poor maneuverability. To minimize the effects of this disadvantage, among other solutions, the incorporation of steerable axles in the semi-trailers has been proposed. This paper presents a steering equation, and a fuzzy-logic controller for a semi-trailer automatic forced-steering system to minimize the off-tracking and the total swept path width, resulting in an improvement of vehicle's maneuverability at low speeds. To accomplish this, the suggested control algorithm considers the articulation angle, and parameters such as vehicle speed and direction. The system was tested on an instrumented experimental semi-trailer during various predetermined test maneuvers.

The tractor-trailer combination is one of the articulated vehicular configurations for road cargo transportation most widely used. Due to the length of these articulated vehicles and the coupling geometrical characteristics, they undergo poor maneuverability. In order to obtain a better understanding of the maneuverability, this paper deals with an experimental one-axle semi-trailer coupled to a light duty pick up truck being used to perform some low speed maneuvers. These test maneuvers include stationary and transient turns, as well as slalom type ones, performed while the semi-trailer axle is set directionally straight or steerable. During each maneuver condition, parameters as planar articulation angle, tractor and trailer yaw rates, and the correspondent steering angles were measured.

The relationship between road geometric design and vehicles moving along it should be in a harmonic way in order to reduce the risk of accident occurrence. As a safety issue, the accident black spot analysis can lead to improvements in traffic signaling and/or to changes to the conflictive roadway section. This paper shows the applicability of the vehicle's dynamic behavior simulation as a complementary tool for evaluating geometrical modifications of roadway sections. A simplified example is described using a typical heavy vehicle, which follows a roadway section under two scenarios, one with an unchanged path and other with some modifications in order to increase safety. Results showed that vehicle's dynamic simulation can offer a detailed perspective of the vehicle's behavior to identify the effectiveness of the proposed changes before they are applied in the practice.

The dynamic behavior of heavy vehicles moving on roads depends on load magnitude and its distribution, and a special concern may be directed to tankers. Liquid cargo at partial filled levels exhibits sloshing during vehicle longitudinal displacement, generating some forces which might alter vehicle's directional response and traction control. To attenuate the sloshing dynamic effect, transversal plates (baffles) are placed inside the container but increasing the structural container mass, arising vehicle's mass center and decreasing vehicle's useful load capacity. An experimental study on the effects of fill level and number of baffles on the sloshing attenuation is presented. For doing so, an instrumented scaled experimental tank of elliptical transversal section is used with water as liquid cargo, and longitudinal sloshing force is measured.