Design and implementation of PLC using arduino due

Abstract

In this project we will present an Arduino based PLC, the PLC uses Arduino Due board as communication path between the input and output interfaces. A new extension of the Arduino framework was used; it introduces multitasking support and allows running multiple concurrent tasks in addition to the single execution cycle provided by the standard Arduino framework. To design Programmable Logic Controller using Arduino there exist two approaches. The first one is to write the program in ladder logic then use compilers directly and compile it to Arduino board. The second approach is to create a plc library inside the Arduino libraries folder, the library that we implemented in this project take advantage of the digital I/O of the Arduino Due. The plc library was coded using c language; it comprises the Basic functions of the PLC respecting the CEI 61131-3 standards. The development of PLC hardware has been designed and improved. This Arduino based PLC is embedded with I/O module such as normally open push buttons, 24VDC power supply and output interface of 5V Relays with LEDs as indicators. I/O field devices are connected using optocouplers installed in order to protect the PLC from any electrical damages in addition to the Darlington Sink Driver (ULN2803) as current amplifier since the current generated by the Arduino pins is so small to drive a relay. Finally to test the functionality of our plc two applications were implemented, the first one is the single task operating conveyor and the second is dual-task Motor.