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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.

This paper presents a study developed in order to improve the aerodynamic performance of an automotive prototype by means of simulations carried out by a software that makes of the finite volume method. The prototype will be built at the Laboratory of Automotive Engineering of the Lutheran University of Brazil - ULBRA. Taking into account the original design of the automotive prototype, three virtual models were generated and analyzed. There were three steps to simulate the aerodynamic behavior on a 3D model: generation of the geometry with the employment of CAD software, generation of the mesh for the faces and volume that involve the car, using specific software, and solving the flow, with a CFD software. The results of the analysis allowed identifying the model with the lowest aerodynamic drag. That model had some modifications on its design, when compared to the original one, like wheels and their housings.

This paper presents a system developed for measurement of force, based on a load cell. The aim was to design a device capable of measuring the components of the force, drag and lift, which acted over automotive spoilers. In order to enable the system to measure the drag and the lift force, it was necessary to develop a system capable of measuring only the components of interest, uncoupling efforts, such as multiple solicitations and vibration. Measurements of force were carried out over an airfoil, employing the measuring system described in this paper. The results showed that the values of the forces that acted over the airfoil were in agreement to the expected. Airfoils are used mainly in automotive racing cars to increase adherence between the tires and ground. Car prepares have made use of theirs experience to determine the best type and angle of attack for the airfoils.

This work presents the results of the development of a small electric car and the study of a Brushless DC Motor, employed to propel the electric car. The aim was selecting a motor with characteristics of operation suited to propel the electric car at a speed from 12 to 20 km/h. The propulsion system has a brushless DC motor and an electronic control unit. The electronic control unit was designed and constructed based on the characteristics of the selected brushless motor. Tests were carried out on the electric car, with the purpose of determining the behavior of the mechanical power required by it, as a function of speed. The results allowed selecting a brushless motor with the following characteristics: 12 V, 5.9 A and 13600 rpm. A theoretical study was developed to determine the suited gear ratio between the speed of the motor and the speed of the wheels of the car.

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.