A monitoring device of a robot system includes: an external force detecting portion configured to detect external force acting on a robot; an area determining portion configured to determine whether or not a predetermined portion of the robot is located within a predetermined area; a force monitoring portion configured to detect collision of the robot based on a first monitoring criterion including at least monitoring of the external force acting on the robot, and when the area determining portion determines that the predetermined portion of the robot is not located within the predetermined area, detect the collision based on a second monitoring criterion not including the monitoring of the external force; and a stop signal generating portion configured to, when the force monitoring portion detects the collision, generate a stop signal of the robot 2 and supply the stop signal to the control device.

A monitoring device of a robot system includes: an external force detecting portion configured to detect external force acting on a robot; an area determining portion configured to determine whether or not a predetermined portion of the robot is located within a predetermined area; a force monitoring portion configured to detect collision of the robot based on a first monitoring criterion including at least monitoring of the external force acting on the robot, and when the area determining portion determines that the predetermined portion of the robot is not located within the predetermined area, detect the collision based on a second monitoring criterion not including the monitoring of the external force; and a stop signal generating portion configured to, when the force monitoring portion detects the collision, generate a stop signal of the robot 2 and supply the stop signal to the control device.