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The main objective of this paper is to make a prospective analysis about the tendencies of the world wide strategies of commercial vehicles development, in relation of the current local and international scenery. It has been done a research by using the Delphi method, which consists into regulate, systematically, the presentation of questions about a specified problem to a group of specialists. In order to guarantee more representative data, it has been adopted three distinct groups: academics, OEMs managers and Tier 1 suppliers managers. The results showed that the three mentioned groups have similar opinion about the necessity of having a product development in the subsidiaries companies; also it has been pointed the necessity of having more taylor made vehicles, due to the intrinsic characteristics of this industry segment.

One of the major challenges on the automotive industry is how to delineate a set of representative and real road loads, for reliability and efficiency during the validation stage on the development process. While several previous studies presented evaluations and results of the tire inflation pressure influence on the fuel consumption, driver comfort, vertical load and braking and handling performance, the objective of this work is to assess the influence of the tire pressure on the forces applied to a commercial vehicle’s steering system. In this regard, the steering link-rod of a truck has been instrumented and used as a load cell, in order to quantify the forces applied to the vehicle’s pitman arm on different tire inflation pressures. The measurements were performed in a static dry-park (lock-to-lock) maneuver and by decreasing the tire inflation pressure of the vehicle’s front loaded axle (6 tons) from 110 psi (7.6 bar) to 50 psi, in steps of 10 psi.

The main objective of this paper is to present the different methods of pavement dimensioning, applied on the Brazilian roads, in order to compare the loads used in the calculation with a real application. It has been used a 4×2 vehicle with the maximum load distribution allowed in Brazil (6 tons in the front axle / 10 tons in the rear axle). It has been instrumented the rear axle with strain gauges to simulate it as a load cell. Measurements were done on a real urban application (Curitiba city - Brazil). Results showed significant differences between the load used in the Brazilian pavement dimensioning methodology and the dynamic vertical load, which could have a direct impact on the pavement lifetime. This paper was supported by three different agency / companies: UNICAMP, Volvo do Brasil and Meritor do Brasil Sistemas Automotivos Ltda.

Powertrain performance analysis is applied by the automotive industry to verify the dynamic performance of the vehicles, which is an outcome of the combination of the engine, the gear box, the driveline, the carrier ratio and the tire size. On this analysis, the main non powertrain factors are the total combined vehicle weight and the route topography. The total combined vehicle weight is a known factor. It is related to the vehicle application and it is restricted to pre-established limits. In general, the route topography is the unlikely factor, due to the huge coverage of the potential paths. Traditionally, the route topography determination is carry out supported by global positioning system (GPS) devices. Appling this methodology, the full route must be tracked by a vehicle equipped with GPS. Its complexity, time and cost increase in case of multiple routes must be tracked, in places geographically remote each other, as different regions, provinces, states or countries.