Safran Electronics & Defense

Sagem Defense Securite

Michel Destelle

Jean-Luc Demange

David Roberfroid

Yves Becheret

Jean Luc Demange

The present invention concerns a method for detecting parasitic movements during static alignment of an inertial measurement unit (), the method being characterised by steps of: receiving radio navigation measurements acquired () by a receiver () from signals previously transmitted by a set of radio navigation satellites (S), estimating () a movement of the inertial measurement unit from the acquired measurements, comparing () the estimated movement with a predefined threshold, indicating () a parasitic movement of the inertial measurement unit when the movement crosses the predefined threshold, in which the estimation () of the movement of the inertial measurement unit () from the acquired measurements comprises the following steps, implemented by the data processing unit for each satellite: calculating () a position variation from a phase of a first radio navigation signal transmitted by the satellite and received by the receiver at an initial reception time, and from a phase of a second radio navigation signal emitted by the satellite and received by the receiver at a subsequent reception time, estimating () a movement of the receiver relative to the satellite between the initial reception time and the subsequent reception time, calculating () a deviation between the calculated position variation and the estimated movement of the receiver relative to the satellite, the estimated movement of the inertial measurement unit depending on this deviation.

Method for detecting parasitic movements during static alignment of an inertial measurement unit, and associated detection device

The invention concerns a method for controlling the integrity of the value of a piece of navigation information delivered by a merging/consolidation device including a plurality of processing modules. Each module generates a navigation solution from measurements coming from one or a plurality of separate navigation devices, which involves defining, for each processing module, a radius of protection, corresponding to a given probability of failure. The method includes defining at least one consolidated area that encompasses protection areas centered on the solution values that are output from the processing modules and that correspond to the radii of protection defined for these modules. The radius of protection of the merging/consolidation device for the probability of failure itself is defined to correspond to the consolidated area.

Integrity control method and merging/consolidation device comprising a plurality of processing modules

The invention relates to a method for integrity monitoring of a primary set of measurements obtained from navigation signals sent by satellites and provided to an integrity control device comprising a plurality of Kalman filters, the method comprising the steps definition, for each Kalman filter, of a secondary set of measurements contained in the primary set, calculation by each Kalman filter of a navigation solution from a respective secondary set of measurements, wherein definition of the secondary sets respects the following principles: each measurement contained in the primary set is present in at least one of the secondary sets, for each p-uplet of measurements of the primary set, p being a predetermined integer greater than 1, at least one of the secondary sets does not contain said p-uplet of measurements, for each secondary set, at least one of the p-uplets is excluded from said secondary set, the method further comprising the steps of: detection, for each navigation solution, of at most p faulty measurements not present in the secondary set from which the navigation solution is prepared, and signalling of at most p faulty satellites in the primary set from respective results of detections.

Growing community of inventors

Boulogne-Billancourt, France

Michel Destelle