Method for managing map data for vehicle

• US 7,440,849 B2
• Filed: 10/12/2004
• Issued: 10/21/2008
• Est. Priority Date: 10/20/2003
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Park, Chang Won, Kim, Young In, Joe, Moon Jeung
• Primary Examiner(s): NGUYEN, TAN QUANG
• Application Number:
  US10/964,417
• Publication Number:
  US 20050085996A1
• Time in Patent Office: 1,470 Days
• Field of Search: 701/208, 701/211, 701/213, 701/201, 701/209, 340/995.1, 340/995.14, 340/995.17, 340/995.18, 340/995.22, 340/995.28, 345/660
• US Class Current: 701/208
• CPC Class Codes: G01C 21/3844 Data obtained from position sensors only, e.g. from inertial navigation

Abstract

The present invention relates to a method for managing map data for a vehicle using a navigation system, wherein upon display of the map data, memory loading for the display of the map data can be quickly performed by reducing the number of access to a physical storage medium with an entire map stored therein.

To this end, when a travel guide map is generated again based on a new location as the position of a vehicle varies, only a certain number of map segments are retrieved from a physical storage medium such as a CD-ROM to generate the travel guide map, thereby making map-displaying speed faster. Further, when the travel guide map is generated again based on the new location as the position of the vehicle varies, map data loading speed can be faster by preventing reusable map segments among map segments loaded on an operation memory from being unnecessarily deleted, retrieved again from the physical storage medium and inserted into the operation memory.

Claims

1. A method for managing map data for a vehicle, the method comprising:

selecting map segments usable for displaying a travel guide map based on a current vehicle location from among a predetermined number of map segments which were loaded in an operation memory in order to display a travel guide map on a display unit based on a previous vehicle location;

designating the selected map segments as properties, and remaining map segments as victims; and

deleting the map segments designated as the victims, retrieving remaining map segments required for displaying the travel guide map based on the current vehicle location from a physical storage medium in which an entire map is stored, and updating the operation memory with the retrieved map segments.

2. The method as claimed in claim 1, further comprising:

loading the map segments in the updated operation memory and the map segments designated as the properties in a screen memory.

3. The method of claim 2, wherein the operation memory comprises a cache memory.

4. The method as claimed in claim 1, wherein selecting the map segments comprises:

calculating coordinates of the current vehicle location using GPS data received by a GPS receiver;

detecting a central map segment including the calculated coordinates of the current vehicle location and a predetermined number of adjacent map segments surrounding the central map segment to display a map with a predetermined size on the display unit; and

selecting map segments, which are identical to the detected central map segment and adjacent map segments from among the predetermined number of the map segments loaded in the operation memory to display the travel guide map based on the previous vehicle location, as map segments usable for displaying the travel guide map based on the current vehicle location.

5. The method as claimed in claim 4, wherein the adjacent map segments are detected based on a degree of proximity to the central map segment.

6. The method of claim 5, wherein the operation memory comprises a cache memory.

7. The method of claim 4, wherein the operation memory comprises a cache memory.

8. The method as claimed in claim 1, wherein the entire map is a map divided into map segments with a predetermined size based on latitude and longitude.

9. The method of claim 8, wherein the operation memory comprises a cache memory.

10. The method as claimed in claim 1, wherein deleting the map segments comprises:

deleting the map segments designated as the victims from the operation memory in a first-in first-out (FIFO) manner, and inserting the map segments retrieved from the physical storage medium into the operation memory.

11. The method of claim 10, wherein the operation memory comprises a cache memory.

12. The method as claimed in claim 1, further comprising:

assigning predetermined marks to the map segments designated as the properties and the victims to identify the map segments before deleting the map segments.

13. The method as claimed in claim 12, wherein the marks are initialized whenever a position of the vehicle varies.

14. The method of claim 13, wherein the operation memory comprises a cache memory.

15. The method as claimed in claim 12, wherein the marks are assigned to the map segments such that a binary bit flag of “

1”

is assigned to the properties while a binary bit flag of “

0”

is assigned to the victims.

16. The method of claim 15, wherein the operation memory comprises a cache memory.

17. The method as claimed in claim 12, further comprising:

managing the map segments designated as the properties such that the properties can be reinserted even though the properties have been deleted from the operation memory in a first-in first-out (FIFO) manner after assigning the predetermined marks.

18. The method as claimed in claim 17, wherein managing the map segments comprises:

deleting the map segments designated as the properties at their turns in the FIFO manner;

adding the deleted map segments to an insertion queue; and

reinserting the map segments added to the insertion queue to the operation memory in a relevant order.

19. The method of claim 18, wherein the operation memory comprises a cache memory.

20. The method of claim 17, wherein the operation memory comprises a cache memory.

21. The method of claim 12, wherein the operation memory comprises a cache memory.

22. The method of claim 1, wherein the operation memory comprises a cache memory.

23. A method for managing map data for a vehicle, the method comprising:

selecting map segments usable for displaying a travel guide map based on a current vehicle location from among a predetermined number of map segments which were loaded in an operation memory in order to display a travel guide map on a display unit based on a previous vehicle location;

designating the selected map segments as properties, and remaining map segments as victims;

deleting the map segments loaded in the operation memory one-by-one in a sequential manner such that the operation memory is filled with the map segments usable for displaying the travel guide map based on the current vehicle location;

determining whether the deleted map segments are map segments designated as the properties or victims;

reinserting the deleted map segments in the operation memory if the deleted map segments are map segments designated as properties.

24. The method as claimed in claim 23, further comprising:

completely deleting the map segments from the operation memory, sequentially retrieving remaining map segments required for displaying the travel guide map based on the current vehicle location from a physical storage medium in which an entire map is stored, and updating the operation memory with the retrieved map segments if the deleted map segments are map segments designated as victims.

25. The method of claim 24, wherein the operation memory comprises a cache memory.

26. The method as claimed in claim 23, wherein the designation of the map segments as properties and the victims is performed using predetermined different marks.

27. The method as claimed in claim 26, wherein the marks are initialized whenever a position of the vehicle varies.

28. The method of claim 27, wherein the operation memory comprises a cache memory.

29. The method of claim 26, wherein the operation memory comprises a cache memory.

30. The method as claimed in claim 23, further comprising:

determining whether the operation memory is full after designating the selected map segments and before deleting the map segments loaded in the operation memory.

31. The method as claimed in claim 30, further comprising:

sequentially retrieving remaining map segments required for displaying the travel guide map based on the current vehicle location from a physical storage medium in which an entire map is stored, and updating the operation memory with the retrieved map segments if it is determined that the operation memory is not full.

32. The method of claim 31, wherein the operation memory comprises a cache memory.

33. The method of claim 30, wherein the operation memory comprises a cache memory.

34. The method of claim 23, wherein the operation memory comprises a cache memory.

35. A method for managing map data for a vehicle, the method comprising:

detecting a predetermined number of map segments required for displaying a travel guide map on a display unit based on a new vehicle location as a position of the vehicle varies, and updating an operation memory with the detected map segments; and

accessing the operation memory instead of a physical storage medium in which an entire map is stored in response to a display request input from a user, and loading the map segments in the updated operation memory in a screen memory.

36. The method as claimed in claim 35, wherein detecting the predetermined number of map segments comprises:

detecting the predetermined number of map segments required for displaying the travel guide map based on the new location as the position of the vehicle varies;

searching the operation memory, and selecting map segments identical to the detected map segments from among a predetermined number of map segments which have been loaded in the operation memory in order to display the travel guide map based on a previous vehicle location;

deleting remaining map segments except the selected map segments; and

retrieving remaining map segments required for displaying the travel guide map based on the new vehicle location from the physical storage medium in which the entire map is stored, and replacing the remaining map segments deleted from the operation memory with the retrieved map segments.

37. The method as claimed in claim 36, wherein detecting the predetermined number of map segments comprises:

calculating coordinates of the current vehicle location using GPS data received by a GPS receiver; and

detecting a central map segment including the calculated coordinates of the current vehicle location and a predetermined number of adjacent map segments surrounding the central map segment in order to display a map with a predetermined size.

38. The method of claim 37, wherein the operation memory comprises a cache memory.

39. The method of claim 36, wherein the operation memory comprises a cache memory.

40. The method of claim 35, wherein the operation memory comprises a cache memory.