Determination of alignments in existing roads by using spline techniques

This paper presents a quick, simple and automatic approximation method that allows the alignments in a road (straights, curves or clothoids) and their respective curvature values to be identified from an approximation point set given by its UTM (Universal Transverse Mercator) coordinates obtained from field data.The method reconstructs the geometry of the road by a smoothing variational cubic spline, computes the curvature function of this spline and approximates the curvature function using a polygonal function formed by trapezoids on the abscises axis. This method permits to obtain alignments that can be used to study any road system that has certain characteristics.