Advanced In-cycle and Cycle-to Cycle On-line Adaptive Control for Thermoforming of Large Thermoplastic Sheets

This paper presents a control system for the thermoforming of large sheets. The system has three main purposes: Its primary purpose is for cycle-to-cycle control of the sheet temperature map as predicted by the thermoforming simulation. Its secondary purpose is to tune the simulation to the actual process through on-line characterization of some of the material and machine characteristics so that the simulation's predictions are reconciled with the machine sensors outputs. Lastly it can characterize on-line a number of independent and fast acting sub-models that allow for in-cycle control of some process parameters.