The invention relates to a closed loop hybridizing device comprising a Kalman filter bank, a virtual platform, a device to calculate pseudo-measurements estimated a priori. The Kalman filter bank comprises a principal Kalman filter adapted to the calculation of corrections to be applied to inertial measurements starting from all available pseudo-measurements, and n secondary Kalman filters adapted to the calculation of corrections to be applied to inertial measurements from a sub-set of available pseudo-measurements. The corrections originate from either the principal Kalman filter when no pseudo-measurement is erroneous or the secondary Kalman filter not affected by an erroneous pseudo-measurement. The corrections are applied simultaneously to inertial measurements and to the input to all other Kalman filters in the Kalman filter bank. In particular, the invention applies to a hybridizing device using information provided by an inertial unit and a satellite navigation system, for example a GPS system.