Figure 4From: Selective control of gait subtasks in robotic gait training: foot clearance support in stroke survivors with a powered exoskeletonSchematic representation of the VMC approach. Z represents the absolute ankle height and Zref the reference ankle height. Lu and Ll represent the upper and lower leg length, and ⊖k and ⊖h the knee and hip angle. Kz indicates the virtual spring stiffness.Back to article page