SLIP-model-compatible and bio-inspired robotic leg with reconfigurable length

We present a novel robotic leg design with reconfigurable length. The design combines key features from bio-mechanical principles into a novel robotic leg with only two actuated degrees of freedom (DOF). The leg configuration with one rotary hip joint and one prismatic knee joint makes it compatible to the Spring Loaded Inverted Pendulum (SLIP) model and will therefore potentially allow direct transfer of suitable control parameters obtained by the simulation of the SLIP model [3]. We have implemented the first prototype and conducted preliminary hopping experiments based on energy-efficient hopping at optimal frequency in human experiment [1]. We measured the ground reaction force and electrical power consumption of the module over a range of hopping frequencies. Our results suggest that the leg driven at its optimal frequency is more dynamic and energy efficient. The externally measured ground reaction forces are very consistent with the results obtained in [1].