Sensoric subsystem of automated guided vehicle: TCP communication between SIMATIC S7 PLC and Arduino

The cheap work with high precision is very necessary in industry for a long time. Research in robotics gives us opportunity for development of automatically guided vehicle controlled by PLC, which can be easily used for supplement transport inside factory, or even for human transport. Main aim of this work is to show, how to replace expensive industrial sensors with integrated communication interface by simple cheap open-source technology. Our solution is focused on TCP communication between Arduino and PLC. The Arduino is extended to Ethernet shield. It makes possibility to connect third-party devices to PLC and save I/O PLC modules. The Arduino pre-process data from ultrasonic and line-following sensors and combine them into one data packet which is send over the network to PLC server.