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Recent developments in robotics have revealed a strong demand for autonomous out-door vehicles capable of some degree of self-sufficiency. These vehicles have many applications in a large variety of domains, from spatial exploration to handling material, and from military tasks to people transportation (Azouaoui C Hong et al., 2002; Kujawski, 1995; Labakhua et al., 2006; Niegel, 1995; Schafer, 2005; Schilling & Jungius, 1995; Wagner, 2006). Most mobile robot missions include autonomous navigation. Thus, vehicle designers search to create dynamic systems able to navigate and achieve intelligent behaviors like human in real dynamic environments where conditions are laborious. In this context, these last few years small automated and non-pollutant vehicles are developed to perform a public urban transportation task. These vehicles must use advanced control techniques for navigation in dynamic environments especially urban ones. Indeed, several research works have recently emerged to treat this transportation task problem. For instance, the work developed in (Gu & Hu, 2002) presents a path-tracking scheme based on wavelet neural predictive control to model non-linear kinematics of the robot to adapt it to a large operating range. In (Mendes et al., 2003), a path-tracking controller with an anticollision behavior of a car-like robot is presented. It is based on navigation and anti-collision systems. The first system uses a Fuzzy Logic (FL) to implement the path-tracking while the second system consists of estimating the trajectories and behavior of surrounding objects. Another work developed in (Bento & Nunes, 2004) treats also the path following problem of a cybernetic car. The developed controller with magnetic markers guidance is based on FL and integrates an anti-collision behavior applied to a bi-steerable vehicle. Other works use a visual control to achieve a desired task such as the work proposed in (Avina Cervantes, 2005). It consists to develop a visual-based navigation method for mobile robots using an on-board color camera. The objective is the use of vehicles in agriculture to navigate automatically on a network of roads (to go from a farm to a given field for example). Although several investigations on the robot navigation problem have been developed (Avina Cervantes, 2005; Azouaoui & Chohra, 2002; Chohra et al., 1998; Gu & Hu, 2002; Kujawski, 1995; Labakhua et al., 2006; Mendes et al., 2003; Niegel, 1995; Schilling & Jungius, 1995; Sorouchyari, 1989), to date further efforts must be made to apprehend and understand |
