Nowadays, the steering system is assumed to be the top safety system in Automotive Industry. Because of its critical role in safety, it was difficult for Iranian automotive manufacturers to work on the design of steering previously. So the main goal of this thesis is to achieve the technology of steering design for heavy and semi-heavy vehicles. The design process is defined here step by step, and in parallel, a steering system has been designed for a new Sweeper car. The chapters of this thesis include the effective parameters on steering and their formulas. Parameters such as the steering components and their types, steering geometry, steering forces, handling and stability of a car are discussed. There is a division in chapters for static and dynamic condition and the results have been verified by softwares such as MSC.ADAMS and also experimental tests. While doing the above, Nissan Junior car and Sweeper car have been studied. It’s led to decreasing the steering error of Nissan and approaching it to zero. The steering system of the sweeper is also newly designed and their components have been analyzed. The steering linkage of the Sweeper car has Ackermann error, and the optimization procedure proposed in this thesis decreased the error by %55. Genetic Algorithm method is used to optimize the mechanism, and neural networks and Taguchi Arrays are used to define the cost function.
