Fusion of data from differing mathematical models

• US 7,194,389 B2
• Filed: 03/25/2003
• Issued: 03/20/2007
• Est. Priority Date: 03/25/2003
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Damron, James J.
• Primary Examiner(s): Shah; Kamini
• Assistant Examiner(s): Gebresilassie; Kibrom K.
• Application Number:
  US10/395,168
• Publication Number:
  US 20030154060A1
• Time in Patent Office: 1,456 Days
• Field of Search: 703/2, 703/6, 701/200, 382/284, 382/293
• US Class Current: 703/2
• CPC Class Codes: G06F 17/10 Complex mathematical operations function generation by table look-up G06F1/03; evaluation of elementary functions by calculation G06F7/544
• CPC Class Codes: G06T 17/05 Geographic models

Abstract

A procedure automatically resolves vertical differences commonly found when merging and combining Digital Elevation Models (DEMs) from different collection and production systems. These systems may employ technologies used in single pass Interferometric Synthetic Aperture Radar (IFSAR), LIght Detection And Ranging (LIDAR), and photogrammetry, as well as DEMs derived from contour based elevation data and GPS point data. This procedure employs sophisticated software checking routines for automatically identifying horizontal and vertical datums used by the differing systems as well as any geoid models employed by them. Normally, all of these sources use different vertical datums and may use different horizontal datums. A preferred embodiment of the present invention automatically recognizes the vertical datums, including those that are associated with the geoid models and the 3-D datums that conventional GIS does not support at present.

Claims

1. A process employing a computer, said process changing an appearance of a boundary between adjacent first and second sections of a map, said first section constructed with data processed with a first mathematical model and said second section constructed with data processed with second mathematical model, said process employing said computer for automatically merging data from said first and second mathematical models each incorporating at least one each horizontal and vertical datums, at least one of either said horizontal or vertical datums differing between said two mathematical models, at least said vertical datums incorporated in a geoid model, comprising:

importing said first and second mathematical models onto said computer for integrating into a geographic information system (GIS) on said computer accessible via said computer;

automatically determining said at least one each horizontal and vertical datums employed by each said first and second mathematical models;

automatically projecting each said determined datums to a common three-dimensional (3-D) datum;

automatically identifying each said geoid model for each said first and second mathematical models;

automatically determining at least one value of separation between corresponding data points within first and second sets of data points, said first and second sets of data points corresponding to said at least one differing datum in each said first and second mathematical models, respectively;

automatically applying a correction to said first set of corresponding data points of said first mathematical model based on said determination of said at least one value of separation and retaining said second set of corresponding data points of said second mathematical model unchanged, wherein said correction adjusts for vertical offsets between said first mathematical model and said second mathematical model; and

employing GIS commands on said computer, automatically fusing into a third mathematical model data on said computer, said third mathematical model representing said corrected first of said mathematical models with data representing said unchanged second of said mathematical models, wherein said third mathematical model changes the appearance of the boundary between said adjacent map sections to allow a viewer of said map to see a realistic representation of the biographical formations of interest along said boundary between said adjacent sections.

2. The process of claim 1 in which said first and second mathematical models are digital elevation models (DEMs), DEM 1 and DEM 2.

3. The process of claim 2 in which sources of data used to build said DEMs are selected from the group consisting essentially of:

LIDAR, IFSAR, SAR, SLR, ground mapping radar, ground penetrating radar, an infrared spectrum sensor array, an ultraviolet spectrum sensor array, a visible spectrum sensor array, and combinations thereof.

4. The process of claim 2 further comprising automatically implementing an accuracy assessment consisting of:

providing Global Positioning System (GPS) data for a geographic area in which said DEM 1 and said DEM 2 overlap; and

using at least one pre-specified statistical algorithm, automatically comparing said provided GPS data to said third mathematical model.

5. The process of claim 4 in which said GPS data have been collected in accordance with the NOAA Technical Memorandum NOS NGS-58.

6. The process of claim 5 in which said GPS data are provided at an accuracy selected from the group consisting of:

10-cm accuracy, 5-cm accuracy, and 2-cm accuracy.

7. The process of claim 5 in which said GPS data are provided at an accuracy of 2-cm.

8. The process of claim 2 further automatically adding at least one geoid model incorporating ellipsoid heights to said third mathematical model,

wherein said addition of said at least one geoid model facilitates automatically deriving orthometric heights relative to a vertical datum.

9. The process of claim 2 in which determining said separation is accomplished by automatically implementing a difference function defined by DEM 1−

DEM 2.

10. The process of claim 4 in which determining said separation is accomplished automatically by first comparing said DEM 1 and said DEM 2 to said GPS data and then automatically correcting DEM 1 to match DEM 2.

11. The process of claim 4 in which automatically determining said separation is accomplished by first comparing said DEM 1 and said DEM 2 to said GPS data and then automatically correcting DEM 2 to match DEM 1.