US 7,398,154 B2 · Method and system for computing road grade data

Abstract

A method of obtaining data for a geographic database is disclosed. Data indicating a plurality of locations along roads including data indicating altitudes at the plurality of locations is provided. Road grade values for a plurality of subsections of the road are computed; each of the subsections is a portion of the road between two of the locations. A plurality of temporary change points are identified as joining two adjacent subsections having road grade values that differ by a value greater than a predetermined amount. Road grade values for each part of the road between adjacent temporary change points are computed. Consecutive parts of the road having road grade values that falls within a predetermined range are grouped into at least one constant road grade section. The geographic database stores data that define the constant road grade section.

Claims17

Dependent claims

A computer-implemented method of representing road geometry for a geographic database comprising:

providing data indicating a plurality of locations along roads, including data indicating longitude, latitude and altitude at said plurality of locations;
computing a horizontal distance between two of said locations;
using a Hough Line Transform to determine a plurality of straight line segments corresponding to a plurality of constant road grade sections along the road, wherein the Hough Line Transform uses data indicating altitudes and said horizontal distance along the road as inputs;
identifying a grade change point corresponding to a location of an intersection of adjacent straight-line segments determined by the Hough Line Transform;
and
storing data that define said constant road grade sections in the geographic database.

3 more elements

Dependencies are inferred from the claim text.

Method and system for computing road grade data

Life of this patent

Method and system for computing road grade data

Life of this patent

Abstract

Claims17