Series-Elastic Ankle Exoskeleton Energy Return

This simulation isolates one specific mechanism from neurorehabilitation exoskeletons: the series-elastic actuator at the ankle that stores elastic energy during controlled dorsiflexion and releases it at push-off. A 3D leg model walks through the gait cycle while a spring visibly compresses and recoils at the ankle; a phase ring shows exactly which part of the stride is loading the spring (amber) versus releasing it (cyan). 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.