Patent ID: 7152022
Filing Date: 2006-12-19
Classification: G01C,G06T

Abstract:
1. A method of determining straight line segments, circular arcs and clothoidal arcs that form a complex curve comprising: providing data indicating a shape of the complex curve along a length thereof; forming a transform of the shape by determining an angle made with a fixed line by a tangent to the shape along the length thereof to provide a plurality of tangent angles; forming a plot of the tangent angles along the length of the complex curve against the length along the complex curve; determining straight lines that fit said plot; using said straight lines that fit said plot to determine at least one of the line segments and circular arcs that form the shape of the complex curve along the length thereof; and representing said complex curve in a geographic database by storing, in said geographic database, data that indicate the at least one of the line segments and circular arcs that form the shape of the complex curve along the length thereof.