System, method and apparatus for searching geographic area using prioritized spatial order

• US 7,363,121 B1
• Filed: 03/30/2007
• Issued: 04/22/2008
• Est. Priority Date: 01/07/2003
• Status: Expired due to Term

• Current Assignee: Garmin International, Inc. (Garmin Limited)
• Original Assignee: Garmin International, Inc. (Garmin Limited)
• Inventors: Chen, Susan S., Barber, Clayton E.
• Primary Examiner(s): To; Tuan C
• Application Number:
  US11/694,457
• Time in Patent Office: 389 Days
• Field of Search: 701/9, 701/301, 340/961, 340/995.14, 340/970, 340/945, 342/26.B, 342/179, 244/180
• US Class Current: 701/9
• CPC Class Codes: B64D 45/04 Landing aids; Safety measures to prevent collision with earth's surface
• CPC Class Codes: G01C 23/00 Combined instruments indicating more than one navigational value, e.g. for aircraft; Combined measuring devices for measuring two or more variables of movement, e.g. distance, speed or acceleration
• CPC Class Codes: G01C 5/005 altimeters for aircraft G01C5/02, G01C5/06 take precedence

Abstract

A spatial data search method, system and apparatus for identifying particular data of significance around a reference vector through the spatial data. The method involves determining a reference vector within a spatial region for which spatial data exists, loading a portion of the spatial data including the data around the reference vector into a memory buffer, and searching the spatial data in a prioritized order. The method, system and apparatus have particular utility in searching geographic data for a terrain awareness and warning system (“TAWS”) and display in an aircraft. Embodiments of the present invention provide advantages over existing sequential and radial search methods, significantly reducing the processing and calculations required and providing faster alerts to pilots.

Claims

1. A terrain awareness and warning system (TAWS) for an aircraft, the TAWS comprising:

a terrain information database configured to store elevation information for a terrain region;

a terrain buffer configured to receive and store elevation information for at least part of the terrain region for an alert cycle;

a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural warning; and

a processor coupled to each of the terrain information database, the terrain buffer, and the look-ahead warning generator, the processor configured to receive at least one signal representative of at least an altitude of the aircraft, a position of the aircraft, and a direction of travel of the aircraft, select data representative of elevation values for a part of the terrain region corresponding to the aircraft position and direction of travel, store the elevation values in the terrain buffer, and search data cells of the terrain buffer in a predetermined prioritized order, the search being dependant upon the vertical velocity of the aircraft and independent of the flight path angle of the aircraft.

2. The TAWS of claim 1, wherein the processor is further configured to maintain an alert list of each data cell of the terrain buffer for which a projected aircraft safety altitude is less than an elevation value for the cell.

3. The TAWS of claim 2, wherein the processor is further configured to calculate an alert status indicator for each data cell in the alert list when a number of cells in the alert list reaches a predetermined number.

4. The TAWS of claim 1, wherein the processor is further configured to monitor movements of the aircraft and responsively modify the predetermined prioritized order.

5. The TAWS of claim 1, wherein the processor is further configured to provide data to the visual display representing the elevation information for the terrain region in relation to a flying altitude of the aircraft for display in conjunction with the terrain clearance alerts.

6. The TAWS of claim 5, wherein the visual display is configured to display the terrain data in a form that also identifies the terrain clearance alerts.

7. A terrain awareness and warning system (TAWS) for an aircraft, the TAWS comprising:

a terrain information database configured to store elevation information for a terrain region;

a terrain buffer configured to receive and store elevation information for at least part of the terrain region for an alert cycle;

a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural warning;

a processor coupled to each of the terrain information database, the terrain buffer, and the look-ahead warning generator, the processor configured to receive at least one signal representative of at least an altitude of the aircraft, a position of the aircraft, and a direction of travel of the aircraft, select data representative of elevation values for a part of the terrain region corresponding to the aircraft position and direction of travel, store the elevation values in the terrain buffer, and search data cells of the terrain buffer in a predetermined prioritized order, the search being dependant upon the vertical velocity of the aircraft and independent of the flight path angle of the aircraft;

wherein the processor is further configured to maintain an alert list of each data cell of the terrain buffer for which a projected aircraft safety altitude is less than an elevation value for the cell; and

wherein the processor is further configured to provide data to the visual display representing the elevation information for the terrain region in relation to a flying altitude of the aircraft for display in conjunction with the terrain clearance alerts.

8. The TAWS of claim 7, wherein the processor is further configured to calculate an alert status indicator for each data cell in the alert list when a number of cells in the alert list reaches a predetermined number.

9. The TAWS of claim 7, wherein the processor is further configured to monitor movements of the aircraft and responsively modify the predetermined prioritized order.

10. The TAWS of claim 7, wherein the visual display is configured to display the terrain data in a form that also identifies the terrain clearance alerts.

11. A terrain awareness and warning system (TAWS) for an aircraft, the TAWS comprising:

a terrain information database configured to store elevation information for a terrain region;

a terrain buffer configured to receive and store elevation information for at least part of the terrain region for an alert cycle;

a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural warning;

a processor coupled to each of the terrain information database, the terrain buffer, and the look-ahead warning generator, the processor configured to receive at least one signal representative of at least an altitude of the aircraft, a position of the aircraft, and a direction of travel of the aircraft, select data representative of elevation values for a part of the terrain region corresponding to the aircraft position and direction of travel, store the elevation values in the terrain buffer, and search data cells of the terrain buffer in a predetermined prioritized order, the search being dependant upon the vertical velocity of the aircraft and independent of the flight path angle of the aircraft;

wherein the processor is further configured to maintain an alert list of each data cell of the terrain buffer for which a projected aircraft safety altitude is less than an elevation value for the cell;

wherein the processor is further configured to calculate an alert status indicator for each data cell in the alert list when a number of cells in the alert list reaches a predetermined number;

wherein the processor is further configured to monitor movements of the aircraft and responsively modify the predetermined prioritized order;

wherein the processor is further configured to provide data to the visual display representing the elevation information for the terrain region in relation to a flying altitude of the aircraft for display in conjunction with the terrain clearance alerts; and

wherein the visual display is configured to display the terrain data in a form that also identifies the terrain clearance alerts.