## The Problem with Rigid Controllers

Most robots trained to imitate human motions have a hidden flaw: they’re **too stiff**. When an imitation-trained humanoid encounters unexpected contact – say it brushes against a table, misjudges an object’s position, or bumps into a person – it treats that deviation as an error and tries to correct it _aggressively_. The result is often _large, uncontrolled forces_ against the obstacle, making the robot’s behavior brittle and potentially dangerous. In ...