Development of an Automated System for the Monitoring and Control pH and Conductivity of a Dampening Solution

Abstract

The influence of dampening solution parameters on the final printing quality has been remarked on many researches during the last decades. There are many parameters that need to be controlled on a fountain solution as pH, conductivity, temperature, and water hardness to obtain a good printing quality. Two of the most important parameters are conductivity and pH level. Conductivity and pH variations can lead to problems due to a disturbed ink / water balance, increased wear of printing plates, and more. This project focuses in the design of an automated control to keep conductivity and pH of the fountain solution in a Heidelberg Press in control. The most challenging topics in modern control theory is non-linear control and pH and conductivity shown a non-linear characteristic. It was recommended after evaluate control theories a Model-Free Adaptive control was selected over PID control, pH fuzzy logic control, and PID error square control. Key Terms: Conductivity Control, Fountain Solution (Dampening Solution), Model-Free Adaptive Control, pH Control.