Inertially Stabilized Range Estimation Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional methods for estimating range in a moving platform, such as an aircraft, are limited by the need to cast hundreds of thousands of rays for Digital Terrain Elevation Data, making real-time range estimation impossible due to processing limitations.
Innovation Solution
Inertially stabilized range estimation mapping is achieved by creating a world map on an azimuth and elevation grid, generating an address table to relate it to an earth-fixed NED coordinate system, and using a programmable device to associate each pixel with an entry from the table, allowing for real-time range estimation by converting AZ/EL coordinates to NED.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional ray casting methods are used to estimate range for Digital Terrain Elevation Data, then measurement precision is improved, but processing time increases making real-time estimation impossible
Solution Approach 1:
The patent pre-calculates and stores range estimation data in lookup tables before real-time operation. During real-time processing, the system simply queries these pre-computed tables rather than performing complex ray casting calculations, thus achieving both accurate range estimation and real-time performance.
Solution Approach 2:
The patent divides the continuous terrain space into discrete grid cells and pre-computes range information for each cell. This segmentation allows the system to store manageable amounts of data in lookup tables while maintaining sufficient spatial resolution for accurate range estimation.
2Measurement precision
If detailed world map data is stored for accurate range estimation, then measurement precision is improved, but device complexity and memory requirements increase
Solution Approach 1:
The patent extracts only the essential range estimation data from the complete terrain model and stores it in compressed lookup tables. Instead of storing full world map data with all geometric details, only the pre-computed range values necessary for estimation are retained, reducing memory requirements and simplifying the data structure.
Solution Approach 2:
The patent transforms the continuous terrain elevation data into discrete range estimation values stored in lookup tables. By changing the representation from continuous geometric models to discrete parameter tables, the system reduces complexity while maintaining sufficient accuracy for range estimation applications.
Data Source
AI summary
An mechanism for range estimation mapping that includes creation of a world map on an azimuth/elevation (AZ/EL) grid, relation of the grid to an earth-fixed north, east, and down (NED) coordinate system through an address table, and association of each pixel in each frame, by a programmable device, with an entry from the address table in order to determine a range is discussed. The associations may be repeated for each frame while an updated world map and address table are generated. When an updated address table is complete, the process may begin anew using the updated data.