Segment Erection Using a Linear Combination of Force and Displacement as the Control Variable

Abstract

Usually segments are set up by a segment erector which is controlled manually. Recently a few segment erectors which can be controlled automatically have been developed to minimize the set up time. In the automated erectors, segment displacement is controlled, that is, a segment is hauled and fitted to the existing segments controlling the displacement. By this method, it is well known that the very accurate control is necessary.
This results in a comparatively expensive control system and also very careful maintenance schedule.
In this paper, the authors discussed on an applicability of control method where a linear combination of force and displacement is chosen as the control variable. By this method, segment is controlled as the conventional displacement control method as far as the segment is not contacted to the existing segments. However, after the contact, force is taken into consideration as the control variable and excessive force is minimized.
The computer simulation revealed that by this control method, a segment is hauled and fitted to existing segment smoothly. Also small scale model experiment is carried out successfully and the results support the calculated one.