(a) Orbital energy of different gait patterns with external force −5 N
(b) Foot trajectories of different gait patterns with external force −5 N
(c) Orbital energy of different gait patterns with external force −15 N
(d) Foot trajectories of different gait patterns with external force −15 N
(e) Orbital energy of different gait patterns with external force −25 N
(f) Foot trajectories of different gait patterns with external force −25 N
Figure 8: Experimental results of different gait patterns with external force (−5 N, −15 N, and −25 N).