Which statement about impedance control in safety-critical human-robot collaboration is true?

• A. Position control is compliant
• B. Impedance control provides compliant interaction
• C. Cobots use force sensing
• D. Impedance control makes motion rigid

Answer: (C)

Impedance control is about shaping how the robot’s motion responds to external forces, effectively making the end effector behave like a mass–spring–damper system. By choosing appropriate stiffness and damping, the robot yields to human contact in a controlled, safe way, which is why it provides compliant interaction. This is the core idea: compliance is built into the interaction dynamics, not into simply reaching a position.

Position control, in contrast, drives to a fixed pose with high stiffness, which is not inherently compliant. Saying impedance control makes motion rigid is the opposite of what it does. Cobots often use force sensing to detect contact and help regulate the interaction, but that detail isn’t what defines impedance control; the defining feature is the controlled, compliant relationship between force and motion that impedance control establishes.