Modelling and application of a bipedal mechanism

Bipedal walking is considered as one of the most important movements of human-being with full of synchronized relative motions of limbs, joints and muscles of both right and left legs with respect to each other, in changing walking velocities. Bipedal walking system is not only composed of dynamic mechanisms but it is also considered as a combination of these mechanisms with various control, sensory and actuator systems. In this work, basic definitions about bipedal walking are given and based on these definitions, mathematical model of a bipedal walker in sagittal plane is derived. After the solutions for the system dynamics are obtained, model based control of the ankle and hip joint trajectories are achieved by using feed forward compensation methodology and simulation results are carried out. Bipedal walking researches are not limited only with the two-legged walking robots and models. Walking aid devices are also related with these studies. For this reason a walking aid device which is an artificial hybrid leg having a polycentric knee joint is designed in this study. Polycentric knee joint considered here is a four bar mechanism. Theoretical background of the artificial leg model, including kinematic and dynamic analyses of the leg is explained and then an experimental setup is built. Two different trajectory control structures which are the point to point position control and the feed-forward compensation with disturbance rejection strategy are developed and experienced on the experimental setup. Results which show the performance of the control strategies are given at the end of the study