Fault diagnostic device of robot system for judging fault by camera image

A fault diagnostic device of a robot system including a plurality of robots, the fault diagnostic device comprising:

• cameras fixed to at least two parts among
• distal ends of the robots, and
• work tools attached to the robots;
• and
• an arithmetic processing device configured to judge a fault in at least one of the robots supporting the cameras and a peripheral device around the robots, based on images of a diagnosis portion captured by the cameras, wherein
• the arithmetic processing device includes a storage storing
• information of the diagnosis portion,
• positions and postures of the robots when the diagnosis portion is imaged, and
• reference images when the diagnosis portion does not have the fault,
• the arithmetic processing device is connected to control devices of the robots via a network, and is configured to acquire the images of the diagnosis portion captured by the cameras via the network,
• the arithmetic processing device is configured to transmit imaging commands to the control devices of the plurality of the robots so as to cause the cameras to capture the images of the diagnosis portion from directions different from each other after changing the positions and the postures of the robots based on the information of the diagnosis portion, and
• the arithmetic processing device is configured to judge whether or not the diagnosis portion has the fault based on the images of the diagnosis portion captured by the cameras, by
• comparing the images of the diagnosis portion captured by the cameras with the reference images, and
• judging that the diagnosis portion has the fault when there is a difference of shapes exceeding a predetermined judgement amount.