On modelling of curl in multi-ply paperboard

Gianantonio Bortolin, Per Olof Gutman, Bengt Nilsson
2006 Journal of Process Control  
This paper describes a grey-box model for the curl and twist of the carton board produced at AssiDomän Frö vi, Sweden. The main equations are based on classical lamination theory of composite materials, and each constituent ply is considered as a macroscopic homogeneous, elastic medium. The model used data from June to September 2004, and shows a general agreement between predicted and measured curvatures. The data were cleaned from outliers by means of the Hampel filter, a nonlinear moving
more » ... ow filter, and with a model based method. Regularization and backwards elimination were used to cope with the low identifiability of the problem. The model was then complemented with a sub-model of immeasurable/unmodelled disturbances estimated with an extended Kalman filter.
doi:10.1016/j.jprocont.2005.04.012 fatcat:7xceoo3rbfbitnxvpis6tbhhja