Abstract: Method for estimating angular errors of coders in a looped system including a rotating actuator, an angle coder producing a position measurements, and a calculation device controlling the actuator, said device receiving a setpoint signal and the position measurements, for looping, and calculating in a corrector a control signal. In a test phase, a specific corrector C?rj(q) is synthesised for a constant rotation speed ?rj, the corrector having zero gain at the corresponding frequency and harmonics, resulting in opening the loop, a matrix relation is established between position measurements and a function of parameters characterizing coder errors and torque ripples, the test phase repeats with different rotation speeds, the matrix relations are concatenated producing an identifiable global matrix relation, the parameters are estimated by resolution of the global matrix relation.

Abstract: Disclosed is a method for reducing the Kerr effect in an interferometry measuring device including a generator configured to emit an input periodic light signal, and a Sagnac interferometer in which two counterpropagating signals travel and combine so as to form a periodic output signal having at least two power values, the method including: determining a phase shift between the two counterpropagating signals a first time, and cancelling out the phase shift; and then determining a phase shift between the two counterpropagating signals a second time; and adjusting the ratio between the average powers of the counterpropagating signals so as to cancel out the value of the phase shift determined in the second determination. Also disclosed is an interferometry measuring device configured to implement such method.

Abstract: Disclosed is a base ship that can receive, in a removable and interchangeable manner, a particular module among various modules, the module being adapted to a functional specialization of the ship. The base ship is similar to a catamaran in its rear portion because it includes two parallel rear lateral volumes that are substantially symmetric with respect to a vertical longitudinal sagittal plane of the base ship, and the removable module is inserted and secured between the two rear lateral volumes of the base ship in order to form a functionalized ship.

Abstract: This relates to a control device for a boat, including members which provides steering, propulsion and safety functions for the boat. The control device includes: sensors; —a central processing unit; at least two peripheral modules which are associated with the member and which each include an interface for receiving data from the sensors; an interface for controlling the member associated therewith; a processing unit; and an interface for communicating with the central processing unit. The processing unit and the central processing unit are programmed to generate instructions for driving the member.

Abstract: This relates to a dosimeter including a light source capable of generating a light beam, an optical coupler-splitter, a radio-sensitive optical fiber, a first photodetector arranged to record a power measurement of the light beam transmitted through the radio-sensitive optical fiber, a reference optical arm, a second photodetector arranged to record a reference power measurement of the light beam transmitted through the reference optical arm, and an electronic system configured to extract a differential radiation induced attenuation measurement in the radio-sensitive optical fiber with respect to the reference optical arm. The light beam is non-polarized or depolarized, or, respectively, the light beam is polarized and the radio-sensitive optical fiber is a polarization-maintaining fiber.

Abstract: Disclosed is a device for connecting two parts of a ship hull, including: a first frame intended to be integral with a first part of the hull; a second frame intended to be integral with a second part of the hull; a tenon integral with the first frame; a mortise arranged in the second frame and able to receive the tenon as a result of a relative translation of the two frames towards each other in a longitudinal direction of insertion; and a pin which is able to be engaged, on the one hand, into a transverse housing provided in the second frame and opening into the mortise and, on the other hand, into a transverse through-hole provided in the tenon, so as to hold the tenon in the mortise. Also disclosed is a hull of a ship including such a device.

Abstract: The invention relates to a system (1, 2) (1, 4) for handling marine (3) or underwater (5) drones, the system (1, 2) (1, 4) comprising a drone interface module (2, 4) and a floating pontoon (1) with two hulls (11) and an arch (10), the pontoon (1) is catamaran-shaped and delimits a downflooded reception space (17), the arch (10) comprises at least one device (12) for attachment to a winch cable, the pontoon (1) comprises devices (13) for detachable attachment to a drone interface module (2, 4) detachably and interchangeably installed in the receiving space (17), the drone interface modules (2, 4) forming an at least partially flooded docking area (23, 42) for the drone (3, 5), the drone interface modules (2, 4) have a lower portion (22, 43) configured to rest stably on a flat surface after the drone interface module (2, 4) has been removed from the pontoon (1).

Abstract: This relates to a device and method for estimating the location of a guided vehicle along a guide, the device including: an attitude sensor of the guided vehicle providing values of attitude component measurements of the vehicle; a memory for storing virtual attitude beacon data including values of one or more of the attitude components of the virtual attitude beacon and at least one virtual attitude beacon attribute value, including at least one position attribute value of the beacon; and a processor configured to perform an activity of a virtual attitude beacon reader, le virtual attitude beacon reader comparing the stored virtual attitude beacon data and the vehicle attitude measurement values in order to detect an instance of a measurement value of the corresponding attitude component exceeding a value of an attitude component of the virtual attitude beacon data, the attitude component advantageously being the geographic heading.

Abstract: Disclosed is a sighting system including a sighting device orientable with respect to a base, adapted to implement a simple and fast on-site calibration method. The sighting system includes for that purpose a cradle holding to the base a sighting device provided with a line of sight. The sighting system includes a first tilt sensor attached to the base, a second tilt sensor attached to the sighting device. The tilt sensors are connected to a central unit adapted to measure a difference between the measurements made by each tilt sensor, in such a way as to quantify a tilt angle between the base and the sighting device, without it being necessary to use a voluminous tool.

Abstract: Disclosed is an echosounder configured to: a) drive the transducers of its emitting antenna to emit first and second acoustic waves having first and second frequencies, these waves being superposed over one another along an axis of superposition that is directed toward a point of the bottom of the subaquatic environment, and b) acquire an echo signal, the frequency of which is equal to the difference between the first and the second frequencies, the echosounder being configured to perform steps a) and b) a plurality of times while varying the orientation of the axis of superposition, and to determine, on the basis of the acquired echo signals, an image representative of the content of the sub-bottom of the subaquatic environment beneath each of the points. Also disclosed is an associated method for characterizing a portion of the sub-bottom of a subaquatic environment.

Abstract: Disclosed is a device for the sealed passage of at least one longitudinal element through a through-hole provided in a partition, including—a frame capable of being permanently fastened in a sealed manner on the partition in order to delimit the hole,—a removable insert, of which at least a central portion is produced by moulding on the longitudinal element in order to produce a sealed connection with the latter, the removable insert being configured to be inserted in a removable and sealed manner in the frame.

Abstract: A cleat for mooring a watercraft at a thrown end of a line has a base surmounted by a body, the base being fastenable to a watercraft deck, the line having a rope and stopper formed by a transverse protuberance, the cleat having an engagement part adjoining the base and a funnel-shaped through-opening to an elongate slot in the body, the slot having a height allowing the longitudinal progression and transverse passage of the rope from the opening towards the interior of the body, the slot leading into a chamber having a minimum dimension greater than the minimum slot height, the maximum dimension of the chamber being less than the dimension of the protuberance forming the stopper so the stopper of a line passing transversely through the body can be blocked against a the body side face both with the rope in the slot and in the chamber.

Abstract: In a method for calculating, by an estimator, an instantaneous velocity vector {right arrow over (Vu)} of a rail vehicle, the estimator receives measurements from an inertial unit at a fixed point in the vehicle body and determines a mathematical model M of the dynamics of the vehicle moving on a track, the model being dependent on the bias of the inertial unit and installation parameters, a virtual sensor is determined based on the model M, the virtual sensor enabling calculation, from model parameters, two theoretical transverse velocities ?vyc, and ?vzc along axes yc and zc, respectively. An iterative estimator calculates {right arrow over (Vu)}, and includes the virtual sensor, the estimator being configured so the two theoretical transverse velocities are zero regardless of the rail configurations, the estimator enabling correction of the biases of the inertial unit and estimate installation parameters. Auxiliary velocity or distance travelled sensors are not used to calculate {right arrow over (Vu)}.

Abstract: Disclosed is an antenna support including: a base; at least one crown including a unit for securing an antenna element; a guide for guiding the crown in rotation around an axis of rotation; a drive for rotating the crown around the axis of rotation; and a unit for determining the angular position of the crown around the axis of rotation. The guide, the drive and the determining unit are mounted on the base on the outer side of the crown.

Abstract: Disclosed is a method for resetting the estimated position of a vehicle, including: —a step of receiving by a RADAR system a real RADAR image, —a step of acquiring an estimated position of the vehicle, —a step of calculating by a computer equipping the vehicle a simulated RADAR image, as a function of the estimated position of the vehicle and of a cartographic model of the environment of the vehicle, —a step of comparing the real RADAR image and the simulated RADAR image, and —a step of correcting the estimated position of the vehicle as a function of the result of the comparison.

Abstract: Disclosed is a multi-axis atom interferometer system, including a source of cold atoms, a laser source generating a first light pulse configured in such a way as to spatially split the source of cold atoms into a first cloud of atoms propagating along a first trajectory along a first axis and a second cloud of atoms propagating along a second trajectory along a second axis, a second light pulse adapted to spatially deflect the first trajectory along the second axis and simultaneously the second trajectory along the first axis towards a first point and a last light pulse adapted to recombine the at least one part of the first cloud of atoms and the at least one part of the second cloud of atoms at the first point, and a detection system measuring an interferometric phase-shift accumulated between the first light pulse and the last light pulse.

Abstract: Disclosed is a passive shock-absorbing system for a sighting apparatus installed on a device including equipment generating the shocks, the system including two rigid plates substantially parallel to one another, via a first plate secured to the part of the device including the equipment and a second plate secured to the sighting apparatus, the plates being connected to one another by a position return component returning the plates to a determined relative rest position after absorbing a shock. The system is characterized in that the position return component includes a line-point-plane positioning unit with balls between the two plates and a set of elastic return members connecting the two plates to one another. A corresponding device is also disclosed.

Abstract: A fiber-optic interferometer is designed to receive and propagate a first single-mode wave along a first optical path and, respectively, a second single-mode wave along a second optical path, the second optical path being the reverse of the first optical path, and to form a first output wave and, respectively, a second output wave, having a modulated phase difference ??m(t). According to the invention, the modulated phase difference ??m(t) is equal to sum of a first periodic phase difference ???(t) having a level equal to ±?, a second periodic phase difference ??alpha(t) having a level equal to ±alpha and a third periodic phase difference ??beta(t) having a variable level between ?beta and +beta, said modulated phase difference ??m(t) comprising per modulation period T at least eight modulation levels among twelve modulation levels and said modulated phase difference between such that: ??m(t+T/2)=???m(t).

Abstract: Disclosed is a device for interaction between a laser beam and a hyperfine energy transition of a chemical species. The device further includes an electro-optic modulator with a single sideband with an input optical waveguide suitable for receiving a source laser beam and an output optical waveguide suitable for generating an output laser beam and an electronic system suitable for generating and applying, simultaneously, a first modulated electrical signal, sin(?1t)) to a first hyperfrequency pulse on a first high-frequency electrode of the electro-optic modulator and, respectively, another modulated electrical signal, cos(?1t)) to the first pulse on another high-frequency electrode of the electro-optic modulator, in such a way as to frequency-switch the output laser beam to a first optical frequency offset from the first pulse with respect to the initial optical frequency.

Abstract: A system for deploying and recovering an autonomous underwater device (AUD) using a surface carrier ship, includes, in addition to the carrier ship, a subaquatic vehicle (SV) guided by a connection wire connected to the carrier ship, the SV able to be positioned in a storage configuration wherein the SV is fixedly but removably joined to the carrier ship in a storage zone, or in a configuration for use, in which the SV, separated from the carrier ship, is in the water and at a distance from the carrier ship while remaining connected by the connection wire, the SV including propulsion, guiding and stabilizing systems and a station for receiving the AUD allowing it to be removably attached to the SV, the receiving station and the AUD including a complementary automated docking unit allowing the AUD to automatically dock with the receiving station during recovery and attach itself thereto.