Robot controller to stop the robot by detecting the contact force between the human

A mass of the workpiece gripped by the gripping portion to provide a robot controller for stopping the robot is different from the mass of the desired workpiece. A robot controller comprises a mass parameter setting section for setting a weight parameter, and a stop command unit which transmits a stop instruction of the robot. Small second upper limit value than the first upper limit value and the first upper limit value is set about the external force. Stop command unit, the robot is stopped when an external force estimated exceeds the first upper limit. Further, the stop command unit is a robot in a stopped state when the average value of the external force exceeds the second upper limit. .FIELD 8