Table 1.

FSM transitions

	Trigger
0 1	Thigh sufficiently behind user (indicated by angle) and not steep-slope walking
0 2	Steep slope walking and leg unloaded
2 0	Leg loaded
1 0	Thigh not sufficiently behind user prior to toe off
2	Leg unloaded
2 3	Knee angle trajectory velocity negative
3 0	Leg loaded or knee reaches full extension

Note. The conditions that identify steep-slope walking are described in the text.