Method for confirming inceptive direction in dead reckoning

Abstract

The invention discloses a method for determining initial directions in dead reckoning. The method comprises the following steps: selecting effective GPS locating points; selecting two GPS locating points, between which the distance is larger than or equal to a threshold and the distance deviation is within a tolerance range, from the effective GPS locating points to determine the initial direction line segment; and calculating the initial direction according to the initial direction line segment. The technical scheme adopting the method for determining the initial direction in the dead reckoning ensures that the determination of the initial direction is more accurate.

Description

technical field [0001] The invention relates to the technical field of navigation, in particular to a method for determining an initial direction in dead reckoning. Background technique [0002] In the field of navigation technology, GPS (Global Positioning System) is the second generation of radio satellite navigation and positioning system in the United States. Normal positioning. In areas where GPS signals are seriously blocked, such as urban roads with many tall buildings, tunnels, or dense trees, GPS will not be able to obtain accurate and reliable location data due to the small number of visible satellites. In this case, GPS is usually combined with other sensors (such as inertial navigation, electronic compass, etc.) to eliminate this effect. That is, when the GPS cannot be positioned reliably due to signal occlusion, the GPS / DR (Dead-Reckoning) system automatically switches to the DR navigation mode to continuously output the position information of the vehicle at ...

AI Technical Summary

Problems solved by technology

[0005] To sum up, the method for determining the initial direction in the prior art dead position navigation has the following defects: First, due to the fact that there are too many vehicles on the crowded urban roads, the speed of the vehicle is generally low, and the urban streets are full of tall buildings, and the occlusion is relatively common. It is difficult to meet the requirements of open conditions

Secondly, the existing technology uses the direction of the line connecting two adjacent GPS positioning points as the initial direction of dead reckoning. Since the distance between the two GPS positioning points is too short, for example, assuming that the vehicle speed is 100km / h, the two GPS positioning points The distance between them is about 28m, and the GPS single-point positioning accuracy is generally above 5m, the resulting direction deviation may reach 20 degrees, resulting in a large initial direction error

Over time, dead reckoning errors will accumulate larger and larger, and its positioning results will soon become unavailable

Images