Automatic aircraft collision avoidance system and method

摘要

The invention is a system and method of compressing a DTM to be used in an Auto-GCAS system using a semi-regular geometric compression algorithm. In general, the invention operates by first selecting the boundaries of the three dimensional map to be compressed and dividing the three dimensional map data into regular areas. Next, a type of free-edged, flat geometric surface is selected which will be used to approximate terrain data of the three dimensional map data. The flat geometric surface is used to approximate terrain data for each regular area. The approximations are checked to determine if they fall within selected tolerances. If the approximation for a specific regular area is within specified tolerance, the data is saved for that specific regular area. If the approximation for a specific area falls outside the specified tolerances, the regular area is divided and a flat geometric surface approximation is made for each of the divided areas. This process is recursively repeated until all of the regular areas are approximated by flat geometric surfaces. Finally, the compressed three dimensional map data is provided to the automatic ground collision system for an aircraft.

主权项

1. A method for using three dimensional map terrain data in an automatic ground collision avoidance system for an aircraft, comprising the steps of:
accessing the three dimensional map terrain data on a computer system; selecting the boundaries of the three dimensional map terrain data to be compressed; dividing the selected boundaries of the three dimensional map terrain data into regular geometric areas; defining each regular geometric area with a corresponding free-edged, planar geometric surface; approximating the three dimensional map terrain data within each regular geometric area using the planar geometric surface so that each regular geometric area is defined by a an independent planar geometric surface; checking the terrain approximation for each regular geometric area to determine if the terrain approximation is within user selected tolerances; dividing the regular geometric areas outside the users selected tolerances into smaller regular geometric areas and approximating terrain data as described above for each of the smaller regular geometric areas; recursively repeating the checking and dividing the steps until all terrain approximations for regular geometric areas fall within tolerances; and, outputting final compressed three dimensional map data to the automatic ground collision system for an aircraft.