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To help the Science and Technology Department of Brazilian Army in its task to define the specifications for the next generation of 6×6 armored personnel carriers, an extensive use of 3D Vehicle Dynamic Simulations was done. Among the studies carried on, a specific set of Simulations was run to help define the best axles configuration for this vehicle. Basically three configurations were evaluated and compared: Twin rear axles and a single steering front axle. Three equally spaced axles, steering in the two front ones. Twin front steerable axles, and a single rear one. Besides some specific military simulations, as trench crossing and vertical step capability, special attention was paid to handling and stability performance of each possible configuration. This work covers the steering, stability and handling aspects of such simulations and shows the comparative results of the three possible configurations

The present paper is a summary of the validation work conducted as part of an SUV suspension development for local market. An extensive use of Vehicle Dynamics Simulation was done during this vehicle development, and the SUV model validation was decided on two traditional handling maneuvers, one to evaluate the transient behavior (ISO 3888 Chicane) and the other for the steady state condition (constant radius curve). A prototype was instrumented and all related data was collected at Pirelli Brazil Test Track facilities. Those data were then introduced in the simulation software, in its validation mode, in order to run a simulation at exactly the same input conditions as the real tests. Such simulation results were afterwards compared with the real data and the required adjustments were done in the simulation model. The real vehicle handling data showed a very satisfactory correlation with the simulation model, with adequate precision for development requirements.

The objective of this paper is to present a work conducted aiming to compare the behavior of different types of tires, using Simulations. During the development phase of a new vehicle, it is very convenient to have any prediction of tire behavior, to make earlier design decisions. This paper describes the use of Vehicle Dynamics Simulation as a tool to make a comparison of different tire sizes and constructions in the same vehicle. In this particular case we will present the result in terms of steering and handling of three different tires, with a combination of two different constructions (same basic dimensions) and two different tire sizes (same basic tire design family), in the same vehicle. Several maneuvers were simulated and all result parameters were analyzed aiming to define the best compromise in terms of vehicle overall performance and safety. The final results were used as a guide to drive future design activities in this particular vehicle.

Traditionally, the suspension development of SUV vehicles presents additional difficulties when compared to other vehicle types, like sedans or even light trucks, due to its inherently high CG height from the ground. This situation is even more critical when designing a suspension set-up for developing countries, due to market particularities such as road conditions and vehicle loading and use. When MMC Automotores do Brasil, Mitsubishi Motors representative for Brazil, decided to produce locally a new SUV as part of the localization process, it was decided to develop a specific suspension tuning for Brazilian conditions. The main objective was to increase suspension travel to improve vehicle capability on rough roads, increasing at same time the comfort level on bad surfaces, but without any critical compromise of vehicle stability and handling.