Off-road trail recording method and apparatus for navigation system
An off-road trail recording method and apparatus for use with a navigation system for recording an off-road trail when a vehicle travels in an off-road area to safely return to the original road. The off-road trail recording is achieved without regard to on/off settings of the off-road trail recording function by the user. The navigation system automatically detects that the vehicle has left the road and starts recording the off-road trail in a background mode without display the off-road trail. When the user turns on the off-road trail recording function later, the navigation system prompts the user to decide whether the off-road trail recorded in the background should be recovered in a normal mode. The navigation system provides various means for recording the off-road trail with reduced resolution when the memory capacity is exhausted or insufficient.
1. An off-road trail recording method for navigation system, comprising the following steps of:
detecting whether a user or user's vehicle (hereafter “vehicle”) has left a road and entered an off-road area where no road segments data are available;
recording off-road trail data in a background recording mode without displaying the off-road trail in response to vehicle's travel in the off-road area when detecting that the vehicle has left the road;
prompting the user to select whether to recover or delete the off-road trail data recorded in the background recording mode indicating the off-road trail connecting the road left off and a current vehicle position when a normal recording mode is activated; and
recording off-road trail data and displaying the off-road trail data on a screen of the navigation system in the normal recording mode in response to vehicle's travel in the off-road area;
wherein the background recording mode is activated automatically when detecting that the vehicle has left the road, and the normal recording mode is activated by the user by turning on an off-road trail recording function of the navigation system.
2. An off-road trail recording method as defined in claim 1 , further comprising a step of displaying the off-road trail connecting the road left off and the current vehicle position on the navigation system when the user selects to recover the off-road trail data recorded in the background recording mode.
3. An off-road trail recording method as defined in claim 1 , wherein said step of recording the off-road trail data in the background recording mode includes a step of storing the off-road trail data in an unused memory area of an off-road trail data storage continuously.
4. An off-road trail recording method as defined in claim 1 , wherein said step of recording the off-road trail data in the background recording mode includes a step of recording the off-road trail data with resolution lower than standard resolution when a memory capacity of an off-road trail data storage is exhausted or insufficient.
5. An off-road trail recording method as defined in claim 4 , wherein said step of recording the off-road trail data with lower resolution includes a step of thinning out the off-road trail data when storing the off-road trail data in the off-road trail data storage.
6. An off-road trail recording method as defined in claim 5 , wherein said step of thinning out the off-road trail data includes a step of determining whether to thin out newest points of the off-road trail data or oldest points of the off-road trail data.
7. An off-road trail recording method as defined in claim 5 , wherein said step of thinning out the off-road trail data includes a step of determining a method of thinning out the off-road trail data based on parameters including a distance of the off-road trail, a time of the off-road trail or a combination thereof.
8. An off-road trail recording method as defined in claim 5 , wherein said step of thinning out the off-road trail data includes a step of determining a method of thinning out the off-road trail data based on parameters including straight or curvature of the off-road trail or surface roughness of the off-road trail.
9. An off-road trail recording method as defined in claim 1 , wherein said step of recording and displaying the off-road trail data in the normal mode includes a step of recording the off-road trail data with resolution lower than standard resolution when a memory capacity of an off-road trail data storage is exhausted or insufficient.
10. An off-road trail recording method as defined in claim 9 , wherein said step of recording the off-road trail data with lower resolution includes a step of thinning out the off-road trail data when storing the off-road trail data in the off-road trail data storage.
11. An off-road trail recording method as defined in claim 1 , wherein said step of recording and displaying the off-road trail data in the normal mode includes a step of selecting whether to delete existing off-road trail data or thin out the existing off-road trail data when a memory capacity of an off-road trail data storage is exhausted or insufficient.
12. An off-road trail recording method as defined in claim 10 , wherein said step of thinning out the off-road trail data includes a step of determining whether to thin out newest points of the off-road trail data or oldest points of the off-road trail data.
13. An off-road trail recording method as defined in claim 10 , wherein said step of thinning out the off-road trail data includes a step of determining a method of thinning out the off-road trail data based on parameters including a distance of the off-road trail, a time of the off-road trail or a combination thereof.
14. An off-road trail recording method as defined in claim 10 , wherein said step of thinning out the off-road trail data includes a step of determining a method of thinning out the off-road trail data based on parameters including straight or curvature of the off-road trail or surface roughness of the off-road trail.
15. An off-road trail recording apparatus for navigation system, comprising:
means for detecting whether a user or user's vehicle (hereafter “vehicle”) has left a road and entered an off-road area where no road segments data are available;
means for recording off-road trail data in a background recording mode without displaying the off-road trail in response to vehicle's travel in the off-road area when detecting that the vehicle has left the road;
means for prompting the user to select whether to recover or delete the off-road trail data recorded in the background recording mode indicating the off-road trail connecting the road left off and a current vehicle position when a normal recording mode is activated; and
means for recording off-road trail data and displaying the off-road trail data on a screen of the navigation system in the normal recording mode in response to vehicle's travel in the off-road area;
wherein the background recording mode is activated automatically when detecting that the vehicle has left the road, and the normal recording mode is activated by the user by turning on an off-road trail recording function of the navigation system.
16. An off-road trail recording apparatus as defined in claim 15 , further comprising means for displaying the off-road trail connecting the road left off and the current vehicle position on the navigation system when the user selects to recover the off-road trail data recorded in the background recording mode.
17. An off-road trail recording apparatus as defined in claim 15 , wherein said means for recording the off-road trail data in the background recording mode includes means for storing the off-road trail data in an unused memory area of an off-road trail data storage continuously.
18. An off-road trail recording apparatus as defined in claim 15 , wherein said means for recording the off-road trail data in the background recording mode includes means for recording the off-road trail data with resolution lower than standard resolution when a memory capacity of an off-road trail data storage is exhausted or insufficient.
19. An off-road trail recording apparatus as defined in claim 18 , wherein said means for recording the off-road trail data with lower resolution includes means for thinning out the off-road trail data when storing the off-road trail data in the off-road trail data storage.
20. An off-road trail recording apparatus as defined in claim 19 , wherein said means for thinning out the off-road trail data includes means for determining whether to thin out newest points of the off-road trail data or oldest points of the off-road trail data.
21. An off-road trail recording apparatus as defined in claim 19 , wherein said means for thinning out the off-road trail data includes means for determining a method of thinning out the off-road trail data based on parameters including a distance of the off-road trail, a time of the off-road trail or a combination thereof.
22. An off-road trail recording apparatus as defined in claim 19 , wherein said means for thinning out the off-road trail data includes means for determining a method of thinning out the off-road trail data based on parameters including straight or curvature of the off-road trail or surface roughness of the off-road trail.
23. An off-road trail recording apparatus as defined in claim 15 , wherein said means for recording and displaying the off-road trail data in the normal mode includes means for recording the off-road trail data with resolution lower than standard resolution when a memory capacity of an off-road trail data storage is exhausted or insufficient.
24. An off-road trail recording apparatus as defined in claim 23 , wherein said means for recording the off-road trail data with lower resolution includes means for thinning out the off-road trail data when storing the off-road trail data in the off-road trail data storage.
25. An off-road trail recording apparatus as defined in claim 15 , wherein said means for recording and displaying the off-road trail data in the normal mode includes means for selecting whether to delete existing off-road trail data or thin out the existing off-road trail data when a memory capacity of an off-road trail data storage is exhausted or insufficient.
26. An off-road trail recording apparatus as defined in claim 24 , wherein said means for thinning out the off-road trail data includes means for determining whether to thin out newest points of the off-road trail data or oldest points of the off-road trail data.
27. An off-road trail recording apparatus as defined in claim 24 , wherein said means for thinning out the off-road trail data includes means for determining a method of thinning out the off-road trail data based on parameters including a distance of the off-road trail, a time of the off-road trail or a combination thereof.
28. An off-road trail recording apparatus as defined in claim 24 , wherein said means for thinning out the off-road trail data includes means for determining a method of thinning out the off-road trail data based on parameters including straight or curvature of the off-road trail or surface roughness of the off-road trail.