Dynamic Line Sag Monitoring Using Image-Based Bézier Curve Fitting

This paper presents an automated system for detecting the sag of overhead transmission lines using image processing. A camera, mounted centrally between two towers, is repositioned using stepper motors to ensure symmetrical alignment with the transmission line. By detecting the lowest point of the line in the image, the system estimates the sag through Bezier curve fitting and converts the pixel-based measurements into real-world dimensions. The proposed system demonstrates high precision and accuracy, providing a reliable method for sag measurement in transmission line monitoring.