| 摘要 |
PURPOSE:To enhance positional detection accuracy, by mounting a means for estimating and operating the error of a present position due to a dead reckoning means and a means for determining the present position based on whether the present position due to a radio navigation means is within a possible present-position-presence range. CONSTITUTION:In a radio navigation means 11, a present position is calculated by operating the navigation radio wave obtained through a receiving antenna 12 by a receiving position operator 14. In a dead reckoning means 15, for example, the output data of a distance sensor 16 measuring the number of rotations of a wheel and that of an azimuth sensor 17 for measuring an advance azimuth are operated by a dead reckoning operator 18 to calculate the present position as the relative position from the present position determined by a present position determining operation means 20. A possible present-position-presence range operation means 19 estimates and operates the error of the means 15 to calculate a possible present-position-presence range. The present position determining operation means 20 compares and operates the present position calculated by the means 11, 9 and the possible present-position- presence range to synthetically determine the present position. By this method, positional detection accuracy and a response speed can be enhanced. |
