| 摘要 |
PROBLEM TO BE SOLVED: To inform a driver of the number of turns to be done until the driver arrives at a destination, thereby solving the tension and the uneasiness of the driver in a car navigation system. SOLUTION: Upon request of a route calculation, the navigation system begins a route calculation to obtain an optimum guide route from the present position of a car to a designation, based on present position data of the car, the destination and map data (S10-S40). Subsequently, the system extracts all 'turn points coordinates TP1, TP2,..., TPN' (S50) locating on the guide route from the present position of the car to the destination, calculates the total of the extracted turn points i.e., 'turn point number S' (S60), and indicates the turn point number with a numeral on e.g. the right upper corner so as to avoid deteriorating the guide route indication on the display, together with the present position of the car, a guide route and a map (S90). |
