| 摘要 |
PURPOSE:To make weighting of each parameter in the total evaluating relationship variable by making the weight of each parameter in the total evaluating relationship variable or the total evaluating function itself variable corresponding to the local searching state of a route. CONSTITUTION:A digital map data is read out from a map data memory medium 5 in a signal processor 3. The optimum route to make each parameter minimum is searched with the use of a total evaluation function. The total evaluation function sets a plurality of costs, e.g. the distance from a starting point, set, on the road map displayed on the screen, namely, from the current position of a vehicle to the destination on the route, the average running time, the road width, the turning number of times in terms of parameters. By representing the optimum route on the road map displayed on the screen by a special color, for instance, the vehicle is guided to run so that the current position of the vehicle is updated and displayed on the optimum route. The weight of each parameter of the total evaluation function or the total evaluation function itself is changed in a predetermined manner corresponding xto the local searching state of the route in order to properly search each time. |
