Real-time model-based control system design and automation for gelcast drying process

Gelcasting is a new method for manufacturing advanced structural ceramics for use, for example, in the aerospace industry. The process involves a drying stage, where moisture, which constitutes approximately a quarter of the mass of the part, is removed in a commercial dryer. The control system design for the gelcast ceramic drying process is complicated by the requirement of minimizing the drying time while avoiding cracking during shrinkage of the part. The paper describes the application of Lyapunov theory for finding an exponentially stablizing controller for the nonlinear drying model. A RealSim/sup (T/)Rapid Prototyping model and the MATRIXx/sup (T)/ design automation environment are used for real time control, as well as feedback system implementation. It is shown that the proposed design and testing automation process with a user friendly interactive animation (IA) graphical user interface (GUI) provides an effective and efficient environment for real time control of the gelcast drying process.