Figure 17.

The deviation between the experimenter’s actual walking trajectory and the reference trajectory in NTV phase space when $\lambda$ varies, the meaning of each part of the figure is as follows: (a) Actual gait trajectory when $\lambda =0.02$; (b) actual gait trajectory when $\lambda =0.2$; (c) actual gait trajectory when $\lambda =2$; and (d) multi-cycle walking trajectory error.