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In this paper, an algorithm is presented based on using bspline function for optimizing tank cross section. This process minimizes fluid c.g. height and overturning moment and improve rollover threshold of tank vehicles. This algorithm receives tank capacity specifications as inputs and offers fourth order bspline function with 10 control points that has more roll stability, and then optimizes it for different filling conditions. This algorithm is based on the third order bspline function with 8 control points, initially. Therefore, with averaging and optimizing, range of control points is modified and the numbers of control points and degree of bspline function are increased. The results show that, the mutation rate is better to be between 4 and 6%, and the number of individuals in each generation should be at least 40. The algorithm presented in this paper, is a fast and accurate method for optimization of tank cross section in different filling conditions. The Algorithm based on GA maintains simplicity applicable for industries and specially has a rollover threshold of 10% higher than conventional tanks.

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Modeling of a Sport Utility Vehicle as it moves on two wheels studied in this paper. Our major purpose concentrated on developing a general criterion to specify rollover threshold. First, model of vehicle as it sustained on two wheels derived that its results used to develop rollover threshold of Sport Utility Vehicles. In addition, these results could be valuable to design new controllers, which are able to prevent rollover at the best state of vehicle dynamics. After vehicle modeling, appropriate model for tire forces and moments picked up from the most related and available references. Then validation accomplished as final part of modeling section. Stability of presented model studied as an important part of this paper. In order to specify rollover threshold as vehicle moves on two wheels, steady-state equations of motion used and based on steady state analyses a new criterion proposed. Next, by designing some maneuvers, simulations accomplished to show applicability of proposed criterion at different situations. As conclusion, presented criterion is more implementable and efficient than other proposed model for rollover threshold and can prospect rollover threshold at various steering angles and longitudinal speeds as model inputs.