Route search method and traffic information display method for a navigation device

• US 7,512,489 B2
• Filed: 02/05/2004
• Issued: 03/31/2009
• Est. Priority Date: 02/05/2003
• Status: Active Grant

• Current Assignee: AutoNavigare LLC
• Original Assignee: Xanavi Informatics Corporation (Hitachi, Ltd.)
• Inventors: Amaya, Shinichi, Sumizawa, Akio, Endo, Yoshinori
• Primary Examiner(s): Nguyen; Cuong H
• Application Number:
  US10/771,743
• Publication Number:
  US 20040225437A1
• Time in Patent Office: 1,881 Days
• Field of Search: 701207-209, 3409951-995, 340/995.19
• US Class Current: 701/209
• CPC Class Codes: G01C 21/34 Route searching; Route guidance
• CPC Class Codes: G08G 1/096716 where the received information does not generate an automatic action on the vehicle control
• CPC Class Codes: G08G 1/09675 where a selection from the received information takes place in the vehicle
• CPC Class Codes: G08G 1/096775 where the origin of the information is a central station

Abstract

A recommended route is searched by the use of traffic information collected in the past. A map/statistical traffic data storage device 3 stores map data including link data of respective links constituting roads on a map, and statistical data including travel time or moving speeds of the respective links determined by statistical values of traffic information collected in the past. Said statistical data is classified every condition of collection of traffic information. A navigation device searches a recommended route from a departure position to a destination by using the map data stored in the map/statistical traffic data storage device and statistical data corresponding to a day type and a weather type which constitute conditions of search, out of statistical data stored in the map/statistical traffic data storage device 3.

Claims

1. A computer-implemented route search method for a navigation device, wherein

the navigation device includes a storage device which stores map data including link data of respective links constituting roads on a map, and statistical data including travel time or moving speeds of the respective links determined by statistical values of traffic information collected in the past, said statistical data being classified according to differing predetermined environmental conditions existing during collection of the traffic information, and the route search method comprises:

setting step which sets a departure position, a destination, and environmental conditions for searching; and

recommended route searching step which searches a recommended route from the departure position to the destination, by using the map data stored in the storage device and statistical data corresponding to the environmental conditions set in the setting step out of the statistical data stored in the storage device;

wherein, in the route searching step, the statistical data corresponding to the environmental condition of respective candidate links constituting a recommended route, is used.

2. The computer-implemented route search method according to claim 1, wherein

the statistical data includes travel time or moving speeds of the respective links every time zone, and

the recommended route searching step searches the recommended route by using, as travel time of respective first candidate links constituting the recommended route, travel time corresponding to a time zone including a departure point of time at the departure position included or travel time obtained from moving speeds corresponding to the time zone concerning and, as travel time of respective (n)th (n≧

2) candidate links constituting the recommended route, travel time corresponding to a time zone including an expected arrival point of time at the termination node of a (n−

1)th candidate link contiguous to the (n)th candidate link or travel time obtained from moving speeds corresponding to the time zone concerned.

3. The computer-implemented route search method according to claim 1, further comprising:

travel time calculating step which calculates travel time or an expected arrival point of time for the recommended route by using travel time of respective links constituting the recommended route used in searching the recommended route in the recommended route searching step, and

travel time displaying step which displays travel time or an expected arrival point of time for the recommended route which is calculated in the travel time calculating step.

4. The computer-implemented route search method according to claim 3, wherein

the statistical data includes a degree of dispersion in traffic information being a source of travel time or moving speeds of the respective links,

the travel time calculating step calculates an error in travel time for the recommended route by using degree of dispersion in traffic information being a source of travel time or moving speeds of respective links constituting the recommended route, said travel time or moving speeds being used in searching the recommended route in the recommended route searching step, and

the travel time displaying step displays travel time or an expected arrival point of time for the recommended route which is calculated in the travel time calculating step, and an error thereof.

5. The computer-implemented route search method according to claim 3, wherein

the statistical data includes a degree of jam every time zone of the respective links,

the travel time calculating step determines a degree of jam in respective sections which are obtained by dividing the recommended route into a plurality of the sections, by using a degree of jam in a time zone corresponding to travel time or moving speeds of respective links constituting the recommended route, said travel time or moving speeds being used in searching the recommended route in the recommended route searching step, and

the travel time displaying step displays travel time for the recommended route which is calculated in the travel time calculating step, and a degree of jam in the respective sections of the recommended route.

6. The computer-implemented route search method according to claim 2, wherein

the navigation device has a current position calculating function, and further comprising:

route guidance step which performs route guidance to the destination by using the recommended route searched in the recommended route searching step and the current position calculated by the current position calculating function, and

expected arrival point of time correcting step which corrects an expected arrival point of time at the destination by calculating travel time for a section between the destination and the current position which disposed on the recommended route and is calculated by the current position calculating function, wherein

the expected arrival point of time correcting step calculates travel time for the section, by using, as travel time for a first link constituting the section, travel time corresponding to a time zone including current time, or travel time obtained from moving speeds corresponding to the time zone concerned, and as travel time for respective (m)th (m≧

2) links constituting the section, travel time corresponding to a time zone including a point of time obtained by adding to current time total travel time between the first link and a (m−

1)th link, or travel time obtained from moving speeds corresponding to the time zone concerned, and adds to current time the travel time for the section to obtain an expected arrival point of time at the destination.

7. The computer-implemented route search method according to claim 2, wherein

the navigation device has a current position calculating function, and further comprising:

route guidance step which performs route guidance to a destination by using a recommended route searched in the recommended route searching step and a current position calculated by the current position calculating function, and

re-search judgment step which compares actual travel time for a section on the recommended route from the departure position to the current position, with travel time for the section concerned on the recommended route which is obtained from travel time for respective links constituting the recommended route and used in searching the recommended route in the recommended route searching step, and judges the necessity of searching a recommended route again according to the result of the comparison, and wherein

the route searching step searches a recommended route to the destination set in the setting step again with the current position calculated by the current position calculating function as a departure position and current time as a departure point of time in the case where it is judged in the re-search judgment step that it is necessary to search a recommended route again.

8. A computer-implemented route search method for a navigation device which has a current position detecting function, wherein

the navigation device includes a storage device which stores map data including link data of respective links, and statistical data including travel time or moving speeds of the respective links constituting roads on the map, said travel time or moving speeds being determined by traffic information statistical values collected in the past, and the route search method comprising:

a setting step which sets a destination position,

a present status data obtaining step which obtains present status data including travel time or moving speeds determined by present traffic information of respective links located in a peripheral region of the current position detected by the current position detecting function, from outside, and

a route searching step which searches a recommended route from the current position to the destination by using the map data and the statistical data stored in the storage device and the present status data obtained in the present status data obtaining step;

wherein the present status data obtaining step obtains a general present status data of respective links around a periphery of the current position, and obtains the present status data when a predetermined data of the general present status data and a predetermined data of the statistical data are different from each other.

9. The computer-implemented route search method according to claim 8, further comprising

general present status data obtaining step which obtains general present status data including a degree of jam in respective links located in the peripheral region of the current position, from outside, and wherein

the statistical data includes a degree of jam in travel every link, and

in the case where a degree of jam in respective links located in the peripheral region of the current position, which is indicated by the general present status data, and a degree of jam in respective links located in the peripheral region of the current position, which is included in the statistical data, are different from each other, the present status data obtaining step obtains present status data of respective links located in the peripheral region of the current position, from outside.

10. The computer-implemented route search method according to claim 8, further comprising

general present status data obtaining step which obtains general present status data including a degree of jam in respective links located in the peripheral region of the current position, from outside, and wherein

the present status data includes a degree of jam in travel every link, and

in the case where the general present status data of respective links located in the peripheral region of the current position has been obtained, and a degree of jam in respective links located in the peripheral region of the current position, which is indicated by the general present status data concerned, and a degree of jam in respective links located in the peripheral region of the current position, which is indicated by the already obtained general present status data, are different from each other,

the present status data obtaining step obtains again, from outside, present status data of respective links located in the peripheral region of the current position.

11. The computer-implemented route search method according to claim 8, wherein

the present status data obtaining step does not newly obtain present status data of respective links located in the current position, from outside, until a predetermined period of time has elapsed since the present status data is obtained.

12. The computer-implemented route search method according to claim 8, wherein

the present status data obtaining step newly obtains present status data of respective links located in the peripheral region of the current position, from outside, in the case where a predetermined period of time has elapsed since the present status data is obtained.

13. The computer-implemented route search method according to claim 8, further comprising

traffic restriction information obtaining step which obtains traffic restriction information for roads from outside, and wherein

the present status data obtaining step obtains present status data of respective links located in the peripheral region of the current position, from outside, in the case where traffic restriction information for the peripheral region of the current position is obtained.

14. The computer-implemented route search method according to claim 8, wherein

the route searching step searches the recommended route by using, as travel time for respective first candidate links constituting the recommended route, travel time in the present status data or travel time obtained from moving speeds in the present status data, and as travel time for respective (n)th (n≧

2) candidate links constituting the recommended route, travel time in the present status data or travel time obtained from moving speeds in the present status data, which is provided in the case that a time difference between an expected arrival point of time at the termination node of a (n−

1)th link contiguous to the (n)th link and a departure point of time at the departure position is below a predetermined value, and travel time in the statistical data or travel time obtained from moving speeds in the statistical data, which is provided in the case that the time difference is not less than the predetermined value.

15. The computer-implemented route search method according to claim 8, wherein

the route searching step searches the recommended route by using, as travel time for candidate links of respective links constituting the recommended route, travel time in the present status data or travel time obtained from moving speeds in the present status data for candidate links located in the peripheral region of the current position, and travel time in the statistical data or travel time obtained from moving speeds for candidate links located outside the peripheral region of the current position.

16. The computer-implemented route search method according to claim 8, further comprising:

travel time calculating step which calculates travel time for the recommended route or an expected arrival point of time by using travel time of respective links constituting the recommended route used in searching the recommended route in the route searching step, and

travel time displaying step which displays travel time for the recommended route or an expected arrival point of time calculated in the travel time calculating step, and wherein the statistical data and the present status data include a degree of jam in every link,

the travel time calculating step determines a degree of jam in respective sections which are obtained by dividing the recommended route into a plurality of the sections, by using a degree of jam in the present status data for the link for which the present status data are used in the route searching step, and a degree of jam in the present status data for the link for which the statistical data are used in the route searching step, among links constituting the recommended route, and

the travel time displaying step displays travel time for the recommended route calculated in the travel time calculating step, and a degree of jam in respective sections of the recommended route.

17. The computer-implemented route search method according to claim 8, further comprising:

travel time calculating step which calculates travel time or an expected arrival point of time for the recommended route searched in the route searching step by using the statistical data stored in the storage device and the present status data obtained in the present status data obtaining step, and

travel time displaying step which displays travel time for the recommended route or an expected arrival point of time calculated in the travel time calculating step.

18. The computer-implemented route search method according to claim 8, further comprising:

route guidance step which performs route guidance to the destination by using the recommended route searched in the recommended route searching step and the current position calculated by the current position calculating function, and

expected arrival point of time correcting step which corrects an expected arrival point of time at the destination by calculating travel time for a section between the destination and the current position which is disposed on the recommended route, and wherein

the expected arrival point of time correcting step calculates travel time for the section, by using, as travel time for a first link constituting the section, travel time for the link determined from the present status data or travel time obtained from moving speeds for the link determined from the present status data, and as travel time for respective (m)th (m≧

2) links constituting the section, travel time for the links determined from the present status data or travel time obtained from moving speeds for the links determined from the present status data, which is provided in the case that total travel time from the first link to a (m−

1)th link is below a predetermined value, and travel time for the link in the statistical data or travel time obtained from moving speeds for the link in the statistical data, which is provided in the case that the total travel time is not less than the predetermined value, and adds travel time for the section to current time to obtain an expected arrival point of time at the destination.

19. The computer-implemented route search method according to claim 8, further comprising:

route guidance step which performs route guidance to the destination by using the recommended route searched in the recommended route searching step and the current position, and

expected arrival point of time correcting step which corrects an expected arrival point of time at the destination by calculating travel time for a section between the destination and the current position disposed on the recommended route, and wherein

the expected arrival point of time correcting step calculates travel time for the section, by using, as travel time for respective links constituting the section, travel time for links located in the peripheral region of the current position in the present status data or travel time obtained from moving speeds for the links concerned in the present status data, and travel time for links located outside the peripheral region of the current position in the statistical data or travel time obtained from moving speeds for the links concerned in the statistical data, and adds to current time the travel time for the section to obtain an expected arrival point of time at the destination.

20. A computer-implemented route search navigation device which has a current position detecting function, comprising:

a storage device which stores map data including link data of respective links, and statistical data including travel time or moving speeds of the respective links constituting roads on the map, said travel time or moving speeds being determined by traffic information statistical values collected in the past;

a setting unit adapted to set a destination position,

a present status data obtaining unit adapted to obtain present status data including travel time or moving speeds determined by present traffic information of respective links located in a peripheral region of a current position detected by the current position detecting function, from outside, and

a route searching unit adapted to search a recommended route from the current position to the destination by using the map data and the statistical data stored in the storage device and the present status data obtained in the present status data obtaining unit;

wherein the present status data obtaining unit obtains a general present status data of respective links around a periphery of the current position, and obtains the present status data when a predetermined data of the general present status data and a predetermined data of the statistical data are different from each other.

21. A computer-implemented route search navigation device, comprising:

a storage device which stores map data including link data of respective links constituting roads on a map, and statistical data including travel time or moving speeds of the respective links determined by statistical values of traffic information collected in the past, said statistical data being classified according to differing predetermined environmental conditions existing during collection of the traffic information;

a setting device adapted to set a departure position, a destination, and environmental conditions for searching; and

a route searching unit adapted to search a recommended route from the departure position to the destination, by using the map data stored in the storage device and statistical data corresponding to the environmental conditions set in the setting device out of the statistical data stored in the storage device;

wherein, in the route searching unit, the statistical data corresponding to the environmental condition of respective candidate links constituting a recommended route, is used.