Development of an automatic online gap-detection scheme for levitated industrial steel-plate conveyance system

For stabilizing the steel-plate conveyance process, efforts on providing appropriate extra electromagnetic forces at the run-out-table of a steel mill have been extensively investigated. Such objectives can be achieved by implementing fixed poles on top of the rollers at the run-out-table to provide the controllable 2-D lift and propulsive forces, and the movable steel plate can then be driven in the desired directions. To realize the entire process, by considering the operational environment at a steel mill, an image-based online gap-detection scheme with real-time parameter calibration process has been developed. Results show that the system that is implemented with a fine-tuned interfacing/ processing scheme can supply rapid and accurate online 2-D gap profiles and, thus, fulfill the design and on-site operational objectives. Index Terms--Conveyance system, image processing, linear induction motor, optical inspection system, steel plate.