Case study of a bottle labelling conveyor automated with an Industrial Shields Arduino based PLC. A rotary encoder on the conveyor goes to two interrupt inputs, a photocell detects each bottle, and two stepper motors with pulse, direction and enable drivers move the label roll and the conveyor. The label motor accelerates to line speed at the moment the label touches the bottle, so the labelling follows irregular gaps and a changing line speed.

The PDF covers the challenge, the line speed and label cycle loops, the system architecture with the signal list and the hardware used. Interactive version: bottle labelling case study online.