Enhancement of lateral control via vision system for printed electronics

One of the important issues in roll-to-roll process control is the control of lateral displacement of web. The problem becomes more challenging as the roll-to-roll process has been applied to printed electronics. Infrared sensors have been used widely for detecting the edge of web. However, the sensor output usually suffers from noise significantly even when the web is at standstill. We present in this paper the implementation of vision system and image processing algorithm and also the application of fuzzy control logic for the lateral control work. Experimental results show remarkable improvement in the control performance compared to the results of using infrared sensors.