Accurate control of the mold interior surface temperature is critical for quality production of plastic parts. Currently, most of the injection molding machines use open loop control without any direct measurement of the mold surface temperature. The control variables are water temperature and valve settings for the cooling/heating water that is circulated through the mold. Recently closed loop systems with thermocouple measurements have become available, but provide only limited usefulness. This proposal discusses an innovative design for two dimensional temperature monitoring and regulation using an infrared sensor, image processing and robust controller design using modern control theory approaches. Experimental data will be collected during Phase I by Nalge Company, a leading plastics manufacturer, to validate the accuracy of temperature estimation using infrared camera, to identify models for controller design and to verify the performance of the closed loop controller. Phase II will consist of actual on-line demonstration of the system in an operational environment.
