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Due to the growing need to reduce the development time of new products, a tendency to rationalize field tests through test benches, in shorter times and with lower costs, has been noted in recent years. During the 90's, such a tendency has generated, in the automotive industry, a great effort to substitute classic field tests, which until recently represented 70% of the development work, for bench tests, with benches well “calibrated” in relation to the traditional methodology. The present work intends to show the development of a test bench to simulate solar radiation and relative humidity effects upon parts and interior lining materials of truck cabins. The traditional test was carried out exposing the cabin to weather conditions in predetermined locations, or in a hot-house, monitoring the cabin interior for temperature and relative humidity variations.

Recent studies in the USA show 2800 passenger casualties/year, due to automobiles and light vehicles impacting against the front structure of medium and heavy trucks at speeds over 45 mph. This same driver or passenger leaves the vehicle and becomes a pedestrian. What is being done in the automotive industry to face this situation? What improvements can be expected in automobiles, trucks and buses in the XXI century? The results obtained in this work show that it is possible and very important for new projects and modernization of commercial vehicles (trucks and buses) to introduce a front bumper concept foreseeing the Passive Safety of third parties (passenger vehicles).

The main objective of engine 3D CFD simulation is nowadays the support for combustion design development. New combustion concepts (e.g. Low Temperature Combustion, HCCI, multiple injection strategies …) could be analyzed and predicted through detailed thermodynamical computation. To achieve this aim many simulation tools are needed: each of them has to be capable to reproduce the sensitivities of combustion design parameters through physically based models. The adopted approach consists of the coupling of different models for 3D-nozzle flow, orifice-resolved spray formation in Eulerian coordinates and combustion. The advantages of the method will be proofed on an operative DI-diesel truck engine case, run with different nozzle geometries.

Heavy trucks are produced with a great variety of vehicle configurations, operate over a wide range of gross vehicle weight and sometimes function in extreme duty environments. Frontal crashes of heavy trucks can pose a threat to truck occupants when the vehicle strikes another large object such as bridge works, large natural features or another heavy-duty vehicle. Investigations of heavy truck frontal crashes indicate that the factors listed above all affect the outcome for the driver and the resulting damage to the truck Recently, a new chassis was introduced for on-highway heavy truck models that feature frontal airbag occupant protection. This introduction presented an opportunity to incorporate the knowledge gained from crash investigation into the process for developing the crash sensor's parameter settings.

New demands for the European Market claimed a new medium duty truck. Aim was not only to comply with new legislations, but also achieve better driving comfort and dynamic characteristics. The development of a new cab suspension was the answer given by means of an international project executed by the Technology Development Center of Mercedes-Benz do Brasil (CDT) with support of other technical divisions of our Development Center in Germany. High-level Teamwork Brazil/Germany at all levels from project coordination down to the plant assembly line was the key to reach an outstanding result with an extra achievement of weight reduction. Complete integration of all involved collaborators in Brazil and in Germany proved to be the main reason to get at the high efficiency shown during the development tasks. This article presents a brief overview of the undertaken development steps together with the challenges and the solutions given to assure the success of the international teamwork.

The logistics process in Brazil and the world represents a significant portion of the cost of manufactured products, either for export or import. The availability of technologies that make the logistic process more efficient directly affects the product’s transportation productivity and makes them more competitive. This paper presents a telemetry model of commercial vehicles integrated with harvest machines in agriculture operations, allowing accurate scheduling of loading and unloading processes at the field. In this study, we introduce a conceptual model of a technological matrix, where the shared topologies of vehicle information processing help predict failures, identification of wear of vehicle and machine’s components. The opportunity is demonstrated to collect data from agricultural machines and combine them with data extracted from trucks. The sharing of information on farm machinery and trucks in real-time establishes an essential change in crop management in the field.

Due to ever soaring fuel costs and even more stringent emission regulations which require more elaborate technical efforts and unfortunately lead to a negative trend on fuel economy as well, todays and future trucking business is extremely challenged. These facts create an urgent requirement for the engine manufacturer to offer an engine with an optimized cost-benefit-ratio for the trucking business. Mercedes-Benz, as the leader in the European commercial vehicle market - of which e. g. high fuel costs, long maintenance intervals and high engine power-to-weight ratios have always been key characteristics - has developed a new class 8 engine for the US market. The MBE 4000 is a 6 cylinder inline engine in the compact size and low weight category, but due to its displacement of 12,8 liters it offers high performance characteristics like heavier big block engines.

Nowadays, the cares with the vibration and the demands with the comfort of self-driven vehicles became basic requirements to the acceptance of a new truck market project more competitive and optimizing solutions that reduce the problems with vibration and comfort. Inside of those, an evaluation of commercial prototype vehicle of medium load will be presented in this work, searching to reduce a flaw still detected on test phase. Measures as change of shock cabin absorber, changes of tires, system of stabilizer bar at the back axis, changes of the front springs and use of linked shock absorber to the mount of the engine will be presented. Evaluations, which were done initially in the vehicle, the diagnosis was the movement happened due to resonance that includes the flexural of the frame, associated to the movement of pitch of the power train and of the cabin.

This work reports the first stage in the experimental optimization of a medium duty truck, equipped with a new engine, with four cylinders and high power, concerning both the noise emission for the environment and the noise level in the passengers' compartment. In the first stage of this work, comparative measurements among the noise levels for vehicles in different configurations were made, in order to identify the most important sources in the vehicle's noise level, as well as to serve as indicative for project improvements. Each system configuration was analyzed separately, in order to obtain a comparative evaluation of the different vehicle configurations along the whole period of measurements.