DOF, joints and motors—what is the difference?

A bigger number does not automatically mean a better hand.

Three counts to keep separate

A joint is a mechanical connection. A degree of freedom is an independent motion coordinate. An actuator produces motion or force. Coupling can make several joints move together, so these counts need not match.

Read a specification carefully

Manufacturers use “active DOF” and “total DOF” differently. Check the mechanism and what is independently controlled. In our directory, an unknown value is a dash, never zero.

Try a comparison

Choose two hands. Compare their fingertip reach, sensing and software alongside DOF. Write one task where the extra movement might help—and one where it might not.