Control

Gravity Compensation

Gravity compensation is the application of joint torques that exactly cancel the gravitational loads on a robot's links, computed from the dynamics model as the configuration-dependent gravity vector, so the mechanism behaves as if weightless. It is the minimal model-based term in nearly every manipulator controller, enabling low-gain compliant behavior, kinesthetic teaching where a human freely repositions the arm, and safe zero-torque-like modes; passive designs use springs or counterweights.

Why it matters for physical AI

Gravity-compensated arms can be physically guided by hand, which is how much kinesthetic demonstration data is collected, and the compliance it permits is foundational to safe operation around people.