Industrie 4.0, modular production processes and machine safety

Working group 1, 'Smart Infrastructure', is working on a dynamic safety concept for simplified, semi- or fully-automatic certification, which will be tested in the Smart Factory KL Industrie 4.0 plant. The concept is based on an industrial Ethernet communication protocol. The whole plant consists of four physically separate production lines that are connected using an automated guided vehicle, the Robotino. If the Pilz PITestop active emergency stop pushbutton is pressed, provided the Robotino is moving freely between modules, only the Robotino is stopped. If the Robotino is docked on to a production line, the E-stop pushbutton stops the connected line. Production on the other lines can continue. This can significantly reduce production downtimes. As a result, for the first time it has been possible to set parameters for the E-stop pushbutton flexibly over individual production lines instead of over the whole plant.

It should also be possible to hot-swap individual modules, without significantly affecting production. Each time a modular production line is modified, new dependencies may arise at the interfaces between the safe plant modules. That is why the whole plant must be reassessed in terms of safety. It is not a matter of simple transferability.

Smart systems are not, therefore, automatically safer, but require the safety aspect to be reassessed. The optimum scenario would be if a simplified, semi- or fully-automated certification procedure could be used for plant expansions or additions. For this reason the working group is developing a system that automatically checks whether a new safety assessment is required after two or more modules are assembled.

If you would like to look at this issue in more depth, Pilz recommends the white paper Safety on modular machines produced by the Smart Factory KL, of which Pilz is a member. Also available is a white paper on Industrie 4.0 from Pilz.