Figure 2From: Biomechanical energy harvesting from human motion: theory, state of the art, design guidelines, and future directionsTypical kinematics and kinetics during a walking cycle. (subject mass = 58 kg, speed 1.3 m/s; cycle frequency 0.9 Hz. In data from [8]: zero ankle angle is defined as 90° between the shank and the foot; zero knee angle is full extension of the knee (straight leg); zero hip angle is with the thigh at 90° with the ground.Back to article page