Figure 1: A quadruple inverted pendulum model.
From: Effect of intermittent feedback control on robustness of human-like postural control system
A model for a human standing tiptoe in the sagittal plane. Each of four links represent foot (MP–ankle), shank (ankle–knee), thigh (knee–hip), and HAT segments, from the bottom. Joint angles were defined as relative angles between adjacent joints except for joint angle of the MP being relative to the vertical line.
