Series-Elastic Ankle Exoskeleton Energy Return (2D Gait View)

This is the 2D sagittal-plane companion to the 3D series-elastic ankle exoskeleton simulation, isolating the same mechanism: a spring at the ankle that stores elastic energy during controlled dorsiflexion and releases it at push-off. A side-view stick-figure leg walks through the gait cycle while a coiled spring at the ankle visibly compresses and recoils; next to it, a gait-phase clock marks exactly which part of the stride is loading the spring (amber) versus releasing it (cyan), with a marker sweeping around once per stride. The same three real controls — spring stiffness, powered motor assist gain, and walking cadence — plus Rigid / Passive / Hybrid presets let you compare an unassisted rigid boot against a purely passive spring and a powered hybrid unit, with a live readout of the patient's own biological ankle work per stride and the resulting reduction in that work versus the rigid baseline. Drag to pan and scroll or pinch to zoom the view.