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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).

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 study is carried out through numerical and experimental methods. The finite element method is used to simulate the support mechanical behavior via modal analysis, and for the evaluation of stress concentration regions through pressure and thermoelastic static analyses, and dynamic analysis. The fatigue life is calculated for the presented stresses. Stress, acceleration and temperature data were obtained through dynamic test. For material evaluation, chemical analysis, hardness and metallographic analysis were carried out. For thoroughness, a failed support fractography will be presented. The objective of this study is to correlate the data obtained by numerical method with experimental data, and as a result, the support failure mechanism was identified. A modified support is presented to avoid the failure for the determined loads. The support within the proposed modifications reduces the current maximum stress in 41% and improved the fatigue life in 4.99e5 cycles.

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.

Curauá fiber processing characterization has been performed throughout the different processing steps. Unsaturated polyester has been used as matrix in the production of curauá reinforced composite samples. Compression molding process has been used to prepare the samples. Tensile strength, impact resistance, flexural strength, Young's modulus and elongation at break have been accessed for curauá composites in comparison with fiberglass composites. Mechanical properties were found not to attend the company's internal standards specification. However, the work has shown some alternatives to solve these problems such as the modification of equipment characteristics and resin formulation, the necessity of incorporation of a higher content of fiber and the possibility of using a new type of filler.

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.