Accurate Gap Filling Using Properly Initialized INS During Periods of GPS Signal Blockage

摘要

Temporary DGPS position loss, in circumstances such asrnan overhead bridge, can be alleviated by an inertialrnnavigation system (INS) that uses onboard sensors torndetermine vehicle position. This work introduces a post-processingrnDGPS/INS integration method based on usingrnthe INS solution during DGPS outages or periods of lowrnaccuracy DGPS position solutions. The INS solution isrninitialized using the DGPS solution before positionrnsolution loss, and measurements from the InertialrnMeasurement Unit (IMU). The final INS solution is arnweighted average of the INS forward and backwardrnsolutions. The initialization methods for different degreernof freedom vehicle positioning models and the developedrnweighting model, are fully explained in this work.rnExperimental results are included.