Positioning of wire suspension system using CCD cameras

A sensor system for measuring tilting angles of a wire which suspends a swinging mass is developed. Two CCD cameras are placed toward the wire on a horizontal plane, and obtain the images of the moving wire respectively. Through the simultaneously obtained two wire images, the angles between the wire and a vertical line are calculated. By feedback control using wire angles measured by the developed sensor, a mass suspended by a two dimensional crane on a horizontal plane is positioned without residual vibration at a target point. Since the developed sensor system is placed near the upper end of the wire regardless of wire length, it is easy to install the developed system in conventional cranes. By using this sensor system, it is expected to automate heavy object positioning, handling and so on.