Land Vehicle Navigation System Based on the Integration of Strap-Down INS and GPS

摘要

The concept and results of integration of a strap-down inertial navigation system (INS) based on low-accuracyinertial sensors and the global positioning system (GPS) for thepurposes of land vehicle navigation have been presented in thispaper. The integration is made by an implementation of extendedKalman filter scheme, both for the initial alignment andnavigation phases. Traditional integration schemes (centralizedand cascaded) are basically held on the usage of high-accuracyinertial sensors. The idea behind suggested algorithm is to uselow-accuracy inertial sensors and GPS as the main source of anavigation information, while the acceptable accuracy of INS isachieved by the appropriate damping of INS errors. The specifiedvalues of damping coefficients can have different influencedepending on the fact whether the moving object is maneuveringor is moving with a constant velocity during the intervals ofabsence of GPS data. The analysis of integrated navigation systemperformances is made experimentally using the data acquiredalong the real land vehicle’s trajectory and by artificialintroduction of intervals of absence of GPS data on the partscharacterized both by maneuver and by constant velocity, and byvarying the values of error damping coefficients.