Kinematic & Dynamic Models of Human Lower Extremity during the Gait Cycle

Studying the principles of human gait is the center of many research studies. In order to analyze and predict the movement of the human walking, the lower extremity of human body is assumed to be a rigid connecting-rod model due to the physiological structure of human body, and the connecting rods are assumed to be connected by joints. Based on the assumptions, a rigid five-bar connecting-rod model of human body in the sagittal plane is developed, and the five rigid rods represent the torso, left thigh, right thigh, left calf, right calf, respectively. Then, mathematical equations of the kinematics and dynamics for human walk on level ground are derived. Since in this study the model is considered as a planar model, only the motion in the sagittal plane is studied. The results from the experiments are compared with the computer simulation results to verify the rigid five-bar linkage model, and the gait information can be predicted effectively by the kinematic and dynamic models.