Design concept of the quasi-passive energy-efficient power-assisted lower-limb exoskeleton based on the theory of passive dynamic walking

Based on the theory of passive dynamic walking, a quasi-passive energy-efficient power-assisted lower-limb exoskeleton (QEPLEX) is developed. The 2D passive bipedal walking model is reviewed and the energy-efficient way to power the model on level ground is presented. Furthermore, the realistic 2D model based on the passive bipedal walking model for the creation of the energy-efficient lower-limb exoskeleton is proposed and the control strategy based on the combination of the hip rotational actuation and push-off compensation actuation is adopted. Eventually, design requirements and mechanical structures of the QEPLEX are outlined.