Patent ID: 8229661

Claim:
Hybrid inertial system onboard a mobile carrier, the system comprising an inertial measurements unit delivering at least one of an angle variation measurements Δθ and a speed variation measurements ΔV, at least one platform for integrating inertial data receiving the at least one of the angle variation measurements Δθ and the speed variation measurements ΔV and producing instantaneous measurements of at least one of the location and of the navigation of the said mobile carrier, at least one exterior sensor delivering observation measurements of the location and/or of the navigation of the said mobile carrier and a multi-hypothesis hybridization filter receiving the said instantaneous measurements and the said observation measurements and delivering corrections to the platforms for integrating inertial data which deliver a hybrid estimation of the location and/or of the navigation of the said mobile carrier, wherein said multi-hypothesis hybridization filter implements at least the following steps: an initialization step performing the generation of a plurality of state vectors XP i 0 representative of the state of the said inertial system comprising on the one hand at least one state dedicated to the location and/or to the navigation of the said mobile carrier and on the other hand hypotheses about defects of the inertial measurements unit, an update step executing, for each of the said state vectors, the phase of readjusting an extended Kalman filtering and producing as output an updated state vector XE i t and its associated covariance matrix PE i t , a propagation step executing, for each of the said state vectors, the phase of propagation of an extended Kalman filtering and producing as output a propagated state vector XP i t , its associated covariance matrix PP i t , and their associated likelihood q i t , a step of determining the likelihood q i t of the said updated state vector XE i t , as a function of the comparison between the observations data and the propagated state vector, a corrections calculation step receiving the plurality of propagated state vectors XP i t , their associated covariance matrices PP i t and their associated likelihood q i t and producing the said inertial corrections of the errors of position and of motion of the said mobile carrier, the said corrections being delivered to the platforms for integrating inertial data.