This paper presents an experimental approach to the problem of designing and executing walking gaits on a dedicated 2-legged machine. We have oriented all our approach towards the experimental analysis of large pattern of walking gaits. This work has lead to the first experimental results obtained on the Bip anthropomorphic robot. The desired movements are designed off line using a model of the robot and tracked on the real system by means of a simple control law. The success of our approach is due both to an efficient mechatronic architecture and to the way it is used to achieve the goal of experimenting walking. The paper presents the system architecture, from mechanical to software issues and also describes the approach developed for designing and executing locomotion. Several results validate the accuracy of our modelling and exhibit the robustness and the efficiency of our controller architecture. We also present and evaluate one of the gaits realized with Bip, using both robotic and biomechanical criteria.