| 摘要 |
PURPOSE: To calculate and display a new recommended route before a vehicle is involved into a traffic jam by starting retrieval successively from a node on the side close to the spot of the traffic jam when the spot of the traffic jam is detected on the recommended route and calculating the recommended route to the destination with the retrieved node as a calculation starting point. CONSTITUTION: When the vehicle starts moving along the recommended route, traffic jam information is received by a traffic information receiver 11 and it is detected whether there is the traffic jam spot on the recommended route in the vehicle advancing direction or not. When there is the traffic jam spot, it is successively retrieved from the side close to the traffic jam spot whether there is a route search object crossing between the current position of the vehicle and the traffic jam spot or not. Then, the new recommended route is calculated by searching the route again with the retrieved route search object crossing as the calculation starting point. Next, the required time in the case of advancing along the new recommended route is compared with the required time in the case of advancing along the original recommended route and when the time difference is within prescribed time, the new recommended route is displayed on a display 8 to perform route guidance. |
