Sagem Defense Securite

Safran Electronics & Defense

David Roberfroid

Jean-Baptiste Eudier

Alexandre Gori

Arnaud Davenel

Jean-Michel Caron

Yves Becheret

Emmanuel Robert

Michel Destelle

Georges-Olivier Reymond

Benjamin Deleaux

Jean-Luc Demange

Flavien Roland

Jean-Francois Keiffer

Vincent Cournou

Jean-François Kieffer

The invention concerns a device () for locating a target, comprising: &#x2014;a camera () that can be oriented in an orientation in view of the target so that the camera acquires an image of the target, and an orientation in view of a star so that the camera acquires at least one image of the star, &#x2014;an inertial unit () configured to calculate position and orientation data of the camera (), &#x2014;a resetting module () configured to a apply stellar resetting to the data on the basis of the image of the star, in order to produce reset data, &#x2014;a location module () configured to estimate a position of the target (T) from the image of the target (T) and the reset data, &#x2014;a communication interface for communicating with an operator station, the camera () passing from one orientation to the other in response to the reception, by the interface, of a command sent by the operator station.

Device for locating a target by stellar correction, intended to be on board a mobile carrier

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

An inertial measurement system for aircraft, the system comprising at least one processor unit connected to at least two inertial units, namely at least one inertial unit of a first type having at least three angular sensors and three linear sensors aligned on three substantially distinct sensing axes, and an inertial unit of a second type comprising at least four angular sensors and four linear sensors aligned on four substantially distinct sensing axes. The system is arranged to calculate one piece of inertial data from the six sensors of the inertial unit of the first type and four pieces of inertial data from four distinct combinations of three angular sensors and three linear sensors selected from the sensors of the inertial unit of the second type, and the processor unit is arranged to compare the four pieces of inertial data from the measurements of the inertial unit of the second type with one another so as to determine whether the inertial unit of the second type has failed.

Inertial measurement system for an aircraft

The invention relates to a method for the autocalibration of an inertial rig comprising an inertial core defining a sensor reference frame, implemented in the course of at least two missions (M, M) each comprising the determination, on the basis of measurements of gyroscopes, of the orientation of the rig in a reference frame comprising the north axis (N) and the vertical axis (Up), the method comprising the implementation:&#x2014;in the course of a mission (M), of an estimation () of drift errors of the gyroscopes for the orientation of the rig at least with respect to the north axis (dgyrN); and&#x2014;in the course of a following mission (M), of a calculation () of corrections of drift errors (DX) of the sensor reference frame (X,Y,Z), on the basis of the estimated drift errors; and&#x2014;of a calculation () of drift errors (X), consisting in correcting drift errors (X) of the sensor reference frame that were calculated during the previous mission (M).

Method for the autonomous calibration of an inertial rig used in static mode

A method of determining a heading by means of an inertial device () providing measurements by means of at least one vibratory gyro (), the method comprising the steps of: &#x2022;positioning the inertial device in such a manner that the gyro extends close to a plane that is substantially horizontal; &#x2022;orienting the inertial device successively in a predetermined number of orientations about a vertical axis, the predetermined number being greater than one; &#x2022;for each orientation, adjusting the electric angle of the vibratory gyro to a predetermined value, the predetermined value of the electric angle being the same for all of the orientations of the inertial device, and taking a measurement; and &#x2022;determining the heading from the measurements and an angle between the orientations.

Method of determining heading by turning an inertial device

A method of determining a heading by means of an inertial device () comprising at least one vibratory angle sensor () having a resonator associated with detector means and means for setting the resonator into vibration connected to a control unit to have a first mode of operation in which the vibration is left free to move in an angular frame of reference of the resonator, and a second mode of operation in which the vibration is maintained at a predetermined angle in the frame of reference of the resonator, and the method comprising the steps of: controlling the sensor in the second mode of operation to maintain the vibration on a predetermined electric angle corresponding to a least-error value of the sensor; and controlling the sensor in the first mode of operation to take a heading measurement, and controlling the sensor in the second mode of operation once the measurement has been taken and until the next measurement in order to maintain the vibration on the predetermined electric angle.

A method and device of determining a speed of rotation of an axially symmetrical vibrating sensor. The sensor has a vibrating member associated with control electrodes and with detection electrodes for generating a vibration presenting an elastic line possessing periodicity of order n and having a position that is variable as a function of the rotation of the sensor. The method includes performing successive evaluations of the speed for a predetermined number of positions of the vibration relative to the electrodes. The positions are geometrically offset relative to each other and the vibration is moved from one position to another by applying a precession command using a pre-established scale factor. The method also includes determining a speed of rotation in function of the evaluations.

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Boulogne-Billancourt, France

David Roberfroid