Locomotion

Capture Point

The capture point is the location on the ground where a bipedal robot must step to bring itself to a complete stop, derived from the linear inverted pendulum model by Pratt et al. (2006). Formally the instantaneous capture point combines center-of-mass position and velocity scaled by the pendulum's natural frequency, and it generalizes to the divergent component of motion (DCM) used in modern humanoid controllers. Stepping controllers track it to recover from pushes.

Why it matters for physical AI

Capture-point reasoning underlies push recovery and footstep placement in humanoid stacks, and remains a key model-based safety layer beneath learned locomotion policies deployed on real bipeds.