Model-based Control for Three-Roll Bending Process of Channel Bar

Abstract

A three-roll bending process with an automatic control system for producing a bar with a U-shaped cross section is studied. The relationship between the bending moment and the curvature of the workpiece is calculated by an elementary method. The calculated relationship is used to build up a process model combining the geometry of the three-roll bending process. This process model is applied to a real time control system for the process. Experiments are performed with the aid of a control system for obtaining products with a constant curvature as well as with continuously varying curvature. The desired curvatures are obtained with good accuracy.