Patent ID: 9671240
Date: 2017-06-06
CPC Classifications: G01C

Claim:
1. A route searching method of a navigation system, comprising: calculating, by a processor, a turning cost from an i-th node to an (i+1)-th node among nodes within a route from a starting point to a destination for a vehicle; calculating, by the processor, a turning cost from the (i+1)-th node to an (i+2)-th node; determining, by the processor, whether the turning cost from the i-th node to the (i+1)-th node is different from the turning cost from the (i+1)-th node to the (i+2)-th node; determining, by the processor, whether the turning direction from the i-th node to the (i+1)-th node is different from the turning direction from the (i+1)-th node to the (i+2)-th node when the turning cost from the i-th node to the (i+1)-th node is different from the turning cost from the (i+1)-th node to the (i+2)-th node; calculating, by the processor, a driving risk degree from the i-th node to the (i+1)-th node when the turning direction from the i-th node to the (i+1)-th node is different from the turning direction from the (i+1)-th node to the (i+2)-th node; comparing, by the processor, whether the calculated driving risk degree is greater than or less than a predetermined reference value; and determining, by the processor, nodes to be excluded from the nodes within the route from the starting point to the destination for the vehicle, based on the comparison, wherein the predetermined reference value of the route between the excluded nodes is increased when the vehicle is driven toward the route between the excluded nodes by comparing an actual driving route of the vehicle with a route provided from the navigation system.