CAR NAVIGATON SYSTEM AND MEMORY MEDIUM FOR STORING NAVIGATION PROGRAM

PROBLEM TO BE SOLVED: To determine advance of a vehicle from an intersection or a branch to a road instantaneously and to deal with the situation quickly by recognizing the image of a feature object at a previously registered intersection or a branch and determining the advancing road from the direction of relative movement of the feature object on the image. SOLUTION: When a signal on the outlet side of an intersection is recognized, for example, from an image data picked up by means of a TV camera mounted on a road guide information I/O unit, the control processor in a navigation system acquires the positional coordinates of the signal on the screen at a specified time interval. If the distance between both coordinates on the screen exceeds a specified distance, relation motion direction (vector) of the signal on the screen is determined. A decision is then made whether a vehicle is advancing straight, turning to the right, turning to the left, or not recognizable based on the area where the vector is present with reference to the straight advance direction (shown by an arrow on the table). If the signal recognition position moves to the right as shown on Fig. C, a decision is then made that a vehicle turned to the left.