ROBOT HAND

The robot hand includes a planetary gear unit into which a rotational power is input from a motor, first and second drive shafts to which a rotational power output from the planetary gear unit is transmitted, a finger having first and second joints respectively driven by the first and second drive shafts. The planetary gear unit includes a sun gear, a planetary gear meshing with external teeth of the sun gear, a planetary arm connected to the planetary gear to coordinately move with a rotation of the planetary gear on its on axis. The sun gear is connected to the motor. The planetary arm is connected to the first drive shaft. An internal gear is connected to the second drive shaft. A resistance generating unit is disposed for making the motion resistance of the internal gear lager than the motion resistance of the planetary arm.