Online distributed state and parameter estimation for feedback control of a curing process

Radiation-based processes can help realize environmentally sound alternative approaches for curing coating materials. To ensure quality of cure with feedback control, the determination of target cure status remains a difficult challenge, particularly when the radiant source needs to move in space for automating the process. In this paper, the problem is cast as a distributed nonlinear state and parameter estimation problem whereby the system model is simplified and a dual extended Kalman filter is set up. This is then used to estimate the cure status on-line from the distributed temperature information captured by one or more infrared cameras. To demonstrate the use of the estimated cure status information for enabling cure level control, output feedback control is implemented with source intensity and the velocity of the moving radiant source as manipulated variables for altering the irradiance on the target surface.