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The depletion of non-renewable energy, emissions of harmful gases to the atmosphere and the impact of fuel consumption in road transport of cargo in Brazil, are motivating the study proposed by this work. In order to reduce fuel consumption, field tests were conducted, where tests were performed for three main segments of heavy transport in the state of Rio Grande Sul We used different combinations of engine power and ratio gear. The test vehicles were operated on a test route that has similarity to the main trade routes of the state that is Porto Alegre - São Paulo, where consumption showed differences between the settings, always indicating the best specification, validating the methodology applied.

This paper describes the design and the analysis of a stub axle front suspension developed to a rear-wheel drive of an automotive prototype. The automotive prototype is a vehicle developed for use on public roads with motor and transmission located at the rear and four-wheel independent suspension, with capacity for two occupants. By means of a finite element software, they were analyzed the efforts that acted on the steering and suspension components that interacted with the sleeve axis The stub axle is subjected to various loads in various ways, due to several conditions imposed by the motion that occur due to movement of the vehicle. They were analyzed three situations during the simulations: straight due to the movement of the vehicle, making a turn and during a braking situation. The analysis of the structure in those three situations allowed obtaining some characteristics, such as their strengths and critic regions where those efforts were higher.

This work presents the results of the study of the forces involved in the rubbing friction between the moving parts of the Otto cycle internal combustion engine. In order to study the friction force, a Honda GX 35 engine was modified and a load cell was attached to its chassis. The friction forces among the internal parts of the engine were transferred to the engine chassis, and, by means of a support, to the load cell. Those forces were measured in several situations of the engine, making possible to identify the amount of friction related to each component. The total measured friction power was equal to 112W, representing about 10% of the developed power of the engine. The results obtained by the tests showed the contribution of each individual part of the engine on the friction losses. By the results, it was possible to propose modifications to reduce the total internal friction of the engine, in order to increase its efficiency.

The Laboratory of Automotive Prototypes of ULBRA has developed researches to construct small automotive cars of high efficiency. The principal aim is to develop and apply new technologies that allow increasing the efficiency of electric and gas engine cars. Those cars received the denomination of Camels. This work presents the results of the study and development of a dynamometer employed in the measurement of torque produced by a small brushless DC motor. That motor was applied to drive a small electric car designed and constructed at ULBRA. Due to difficulties in finding a load cell to measure loads smaller than 20 N, a ring-type load cell was constructed to measure static force in uniaxial direction, range from 0 to 20 N. The load cell had strain gages connected to a data acquisition system. The acquisition system was connected to PC via USB. The measurement system consisted of an analog digital converter (A/D), model MyPCLab, produced by NOVUS.

This paper consists in a definition and analysis of rear suspension geometry to an off-road vehicle. The suspension selection was accomplished through the study of its geometric characteristics to design its dimensions and position of installation in the vehicle according to the expected behavior. The current suspension of the vehicle, on the front and rear axles, was analysed for understanding its dynamic behavior. The vehicle submitted to analysis was a “Mini-Baja”, off-road prototype, which is used to run nationals competitions between engineering colleges. Its top speed is 50 km/h and its turn diameter is 8.2 m.