Patent ID: 7711482

Claim:
A INS/GNSS hybrid system with integrity monitoring, comprising: a barometric module BARO delivering measurements of barometric altitude MBA; an inertial measurement unit UMI delivering angle increments Δθ and speed increments ΔV; a virtual platform PFV receiving the angle increments Δθ, the speed increments ΔV and producing inertial positioning and speed data PPVI constituting respectively a hybrid position and a hybrid speed; a satellite-based positioning receiver GNSS operating on the basis of a constellation of N tracked visible satellites, and producing raw measurements, MB i of the signals transmitted by these satellites, i denoting a satellite index and lying between 1 and N; a Kalman hybridization filter MKF receiving the inertial positioning and speed data PPVI, the measurements of barometric altitude MBA, and the raw measurements MB i of the signals transmitted by the N satellites, said filter delivering: a hybrid correction HYC comprising an estimation of a state vector VE corresponding to the errors of the hybrid system and obtained by observing the deviations between the inertial positioning and speed data PPVI and the raw measurements MB i , and a variance/covariance matrix MHYP of the error made in the estimation of the state vector VE; a bank of N secondary filters KSF i each receiving the inertial positioning and speed PPVI, the measurements of barometric altitude MBA, and the raw measurements MB i of the signals transmitted by the tracked satellites except the satellite of index i, said secondary filters KSF i delivering hybrid parameters SHYP i comprising an estimation of a state vector EVE i corresponding to the errors of the hybrid system, calculated by observing deviations between the inertial positioning and speed data PPVI and the raw measurements of the signals transmitted by the tracked satellites except the satellite i SPP i , and a secondary variance/covariance matrix P i of the error made in the estimation of the state vector EVE i ; a calculation module CAL receiving the hybrid parameters SHYP i and the variance/covariance matrix, MHYP, said calculation module CAL determining a horizontal protection radius R T associated with the hybrid position, and, when components of the estimation of the state vector EVE i relating to the position are greater than a detection threshold TH i , triggering an alarm upon a failure of a secondary filter KSF i , and optionally identifying a failed satellite from among the N tracked visible satellites, wherein the secondary filters KSF i and the virtual platform PFV furthermore receive the hybrid correction HYC.