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Object-oriented programing has been around for more than 50 years and has changed the way we develop computational algorithms. Although the concept of objects in programming was introduced with a physical systems modeling tool, most modelling is done today with procedural programming. This paper aspires to show the benefits of object-oriented programming in contrast to procedural programming. This was done by taking a case study in which we analyze the model of the vehicle electric system. The system was partially modelled using Simulink for procedural programming and using Simscape for object-oriented programming. As a result, the object-oriented model was simpler to read and understand. It also provided an interface that facilitates expansion, whereas the procedural model needed to be rebuilt to accommodate changes in the structure and presented higher complexity.

Since in 1978 the Robert Bosch GmbH first started with series production of anti-lock braking systems over 150 million of their units have been installed world-wide. The current ABS generation 8 is a modular system which permits ABS, TCS and ESP® braking control systems to be implemented as an integrated product family. Although the benefits of ABS in road traffic safety by significantly improving steerability and car control while braking are well known in Europe, USA, and Japan, there are still weak installation rates in emerging markets like Brazil: For vehicles sold in 2006 in the Brazilian market, the installation rate is about 14%. Major reason for this situation is the cost of ABS unit influenced by development and application work, which usually has to be carried out for each car individually. To address this Bosch is considering a cost optimized system in between today's full performance ABS and a standard braking system without modulation.

Although quench factor analysis has been used by many researchers in predicting the performance of a quenchant to strengthen aluminum, it has rarely been applied to steel quenching. However, quench factor analysis posses a number of advantages over current empirical methods or more recently employed finite element thermophysical property modeling. For example, quench factor analysis can address the non-Newtonian cooling process involved with many processes utilizing vaporizable quenchants. Quench factor analysis predictions of as-quenched hardness can be successfully performed with an Excel Spreadsheet calculation. Finally, quench factors can be easily utilized in constructing databases for quenchant characterization and selection.

A mathematical model and computational system were created for Diesel engine cooling system analysis. Interdependent mathematical models describe the whole cooling system. Computational program inputs were taken from Mercedes Benz tests and the global heat transfer coefficient of the radiator, engine heat flux, radiator heat flux and fan power consumption outputs were calculated during the test. Cooling system analysis and optimisations may be obtained, reducing fuel consumption, gas emissions and engine wear for several conditions, vehicles and designs.

The aim of this paper is introduce an original and innovative technique called performance charts to obtain the performance of heavy vehicles during braking process. Several performance charts are shown for an example heavy vehicle and are discussed the results obtained, that include values of stopping distance, maximum and average deceleration, efficiency and others obtained during the braking process of the example vehicle. As well is shown the importance of the application of this technique on the braking system definition process of heavy vehicles, on the orientation of the users of these vehicles or fleet-owner and on the verification of legal requirements established by regulations of braking performance of these vehicles.

The time and the distance traveled during the acceleration and the velocity retaking are parameters used for the comparison and the project of vehicles. In this paper equations for the calculation of those parameters are presented. Several criteria are presented for the shift gears. It is also verified the occurrence or not of total slip during the acceleration of the vehicle. The theoretical models were implemented in a developed computational system. Such system was applied in a Mercedes-Benz do Brazil sample vehicle, in order to facilitate comparisons between the simulate values and the experimental road tests.

The heat treatment used in manufacturing process of automotive parts are very important, and among them, particularly the quenching of steels. In this heat treatment the quenchant capacity of heat extration is a very critic parameter, and once specified, its cooling features must be preserved to ensure the maintenance of the mechanical properties of components, which will determine the project functionality and durability. The best way to control the quenchant during quenching is through the continued control of the quenchant cooling curve of the and its respective cooling rate. In this work was utilised a computer controlled data acquisition system, which allow in actual time, to get values of temperature and time during the cooling phenomena. This data are processed to give immediately values of the cooling rate. This system is applied to different quenchants, such as: water, polymeric solutions and oils.

The study, design, optimization, verification and forecast of the braking process of road vehicles normally uses discrete positions of gravity of the loaded vehicle. Generally these are positions of the centre of gravity (c.g.) for the conditions of operational weight and maximum total weight (full load). The performance limits of the vehicle are thus obtained in these two weight conditions in a discrete form. The present work developes an alternative form for the above mentioned calculations, using the “static balance” or “centre of gravity envelope” technique used in Aeronautical Engineering (Roskan, 1972).