Stephen P Robinson

US Patent:

60322195, Feb 29, 2000

Filed:

Aug 1, 1997

Appl. No.:

8/904638

Inventors:

Stephen C. Robinson - Olathe KS
Darin J. Beesley - Kansas City MO
Thomas H. Walters - Gardner KS

Assignee:

Garmin Corporation

International Classification:

G06F 1200

US Classification:

711 1

Abstract:

A system for buffering data has a processor connected to a memory for storing mass data, connected to a single buffer having a plurality of buffer storage locations in a chain, and connected to a plurality of counters, wherein each counter corresponds to one of the buffer storage locations. The processor selects a sector of memory containing desired data associated with an open file, scans the buffer storage locations to determine whether the data is in the buffer and, when the data is not within the buffer, reads the data from the selected sector of memory into a selected buffer storage location that is unallocated to an open file. The processor then points to that allocated buffer storage location, so that the data can be retrieved from the buffer for processing. As additional data is desired that is not found in the buffer, the buffer storage location allocated to the open file is de-allocated and, if not allocated to any other open files, moved to the beginning of the chain of buffers. The sector of data containing the desired data is then read into a selected buffer that is not allocated to an open file, preferably the last unallocated buffer in the chain of buffers.

US Patent:

62526057, Jun 26, 2001

Filed:

Aug 1, 1997

Appl. No.:

8/905297

Inventors:

Darin J. Beesley - Kansas City MO
Stephen C. Robinson - Olathe KS
Thomas H. Walters - Gardner KS

Assignee:

Garmin Corporation

International Classification:

G06F 1500

US Classification:

345441

Abstract:

A system and method for constructing an R-Tree index structure, and packing spatial data in the structure to permit parameters of the R-Tree to be constructed to be selected, within provided ranges, by an operator of the system. The spatial data features to be packed into the R-Tree constructed, are sorted, according to fractal geometry, and placed in a table of records. Each record is individually selected from the table, and data associated with each record is temporarily stored in one of a plurality of buffer storage locations according to a plurality of packing algorithms. The data in a buffer storage location is split, into first and second groups of data, upon the occurrence of one of a plurality of predetermined conditions. Data is selectively removed from the buffer for placement in the R-Tree being packed, such that data representing nearby geographical areas is most optimally clustered together. A portable electronic device such as a navigational aid, has a processor, a display, an input, and a memory, all housed by a housing, wherein the memory has spatial data indexed by an R-Tree index embedded therein.

US Patent:

61889555, Feb 13, 2001

Filed:

Dec 30, 1998

Appl. No.:

9/223553

Inventors:

Stephen C. Robinson - Olathe KS
Darin J. Beesley - Overland Park KS
Thomas H. Walters - Gardner KS

Assignee:

Garmin Corporation

International Classification:

G06F16500

US Classification:

701200

Abstract:

A method and device implementing a three-level hierarchy for storing, recalling and processing navigational and graphical data. A vehicle is equipped with an electronic navigation thoroughfare planning device capable of calculating the distance to a desired thoroughfare. To calculate a distance, a driver inputs a plurality of variables, including cartographic data and a final desired destination, as well as several potential additional variables. Upon receiving the driver inputs, the navigation device implements a three-level hierarchy for storing, recalling and processing cartographic data. After the cartographic data is stored in memory, the navigation unit can calculate distance to a thoroughfare utilizing a cascading search method beginning with searching the most specific first level and progressing to the broader second and third levels until a common network between the two locations is established. The navigation device can also utilize the three level hierarchy to display cartographic data as a graphical map on the unit utilizing the same cascading method to display detail on the display screen and locate the specific details on any coordinate on the screen. Therefore the navigation unit utilizes the same three level hierarchy to calculate distance to a desired destination and to display a graphical representation of the map.

US Patent:

59959703, Nov 30, 1999

Filed:

Aug 1, 1997

Appl. No.:

8/904642

Inventors:

Stephen C. Robinson - Olathe KS
Darin J. Beesley - Kansas City MO
Thomas H. Walters - Gardner KS

Assignee:

Garmin Corporation

International Classification:

G06F 1202
G06F 9302

US Classification:

707101

Abstract:

The storage space required for representing geographic features is reduced by determining an optimum number of bits that can be used to store coordinate data along each separate axis. Any coordinate change that cannot directly fit within the optimum bit size is subjected to an escape sequence made up of one or more special values and a normal value that fits in the optimum bit size. The special values are obtained by a predetermined calculation for each bit size. If all changes for one axis are in the same direction and special values are not needed, a global sign can be used to further enhance use of the available space on the storage medium.