Control

Compliance

Compliance is the ability of a robot to yield under external forces, the inverse of stiffness, arising passively from elastic mechanical elements or actively from control laws that modulate the relationship between force and displacement. Compliant behavior absorbs impacts, accommodates pose uncertainty during contact, and reduces peak forces in human-robot interaction. It is quantified by stiffness and damping parameters, often specified per Cartesian axis for manipulation tasks.

Why it matters for physical AI

Contact-rich skills succeed on real hardware largely because compliance absorbs the residual errors of perception and learned policies, turning would-be jams and crashes into graceful accommodation.