Abstract: An acceleration-measuring sensor assembly includes an accelerometer subassembly with three measurement axes, mounted in a housing equipped with securing elements, and configured to determine an acceleration along a principal axis A, the assembly comprising: a single-axis principal accelerometer with a seismic mass moving in a straight line along a principal axis A, measuring acceleration along the principal axis A which is misaligned with respect to a reference axis Y by at most 50 mrad, a secondary accelerometer having at least two measurement axes and measuring respectively along two axes X and Z which with the reference axis Y form a direct orthonormal trihedron (O, X, Y, Z), the measurement precision of the two-axis accelerometer along each of its axes being at least ten times inferior to the measurement precision of the single-axis accelerometer, and an electronic processing unit configured to calculate a compensated acceleration S.

Abstract: A microelectromechanical system comprising an assembly of layers stacked in a stacking direction comprises an active layer made of single-crystal silicon comprising an active structure, and first and second covers defining a cavity around the active structure, the active layer interposed between the first and second covers, the second cover comprising a single layer made of single-crystal silicon. The assembly comprises a decoupling layer made of single-crystal silicon and comprising: an attaching element fastened to a carrier, a frame encircling the attaching element in the plane of the decoupling layer, and a mechanical decoupling structure connecting the frame and the attaching structure, the mechanical decoupling structure allowing the attaching element to be flexibly joined to the frame. The frame is secured to the silicon layer of the second cover and at most one film of silicon dioxide is interposed between the frame and silicon layer of the second cover.

Abstract: A microelectromechanical system comprising an assembly of layers stacked in a stacking direction comprises an active layer made of single-crystal silicon comprising an active structure, and first and second covers defining a cavity around the active structure, the active layer interposed between the first and second covers, the second cover comprising a single layer made of single-crystal silicon. The assembly comprises a decoupling layer made of single-crystal silicon and comprising: an attaching element fastened to a carrier, a frame encircling the attaching element in the plane of the decoupling layer, and a mechanical decoupling structure connecting the frame and the attaching structure, the mechanical decoupling structure allowing the attaching element to be flexibly joined to the frame. The frame is secured to the silicon layer of the second cover and at most one film of silicon dioxide is interposed between the frame and silicon layer of the second cover.

Abstract: The invention relates to vibrating micro-systems, and notably but not exclusively to pressure, acceleration, or angular speed micro-sensors with a resonator in an evacuated cavity. The resonator (10) with a vibrating element is placed in an oscillating circuit controlled by a closed-loop control, the oscillating circuit supplying an oscillating signal y(t) at a resonance frequency Fp representing the measurement of a physical quantity. The resonance frequency is calculated by counting pulses over a time window. The sensor furthermore comprises means for calculating a continuity parameter Pc representing the variations in the result of the calculation of the resonance frequency over the course of the successive time windows, and means for comparing the parameter Pc with a threshold in order to deduce from this information on the degradation of the precision of the sensor.

Abstract: A micro-system, for example a micro-sensor, includes a resonator 10 with vibrating element(s) 11 receiving an excitation signal E of a loop 20 for automatic gain control, as a function of an amplitude setpoint (C) and providing as output a signal y(t) defined by a peak amplitude having a nominal value A0 dependent on the said setpoint and a resonant frequency. The micro-sensor integrates a circuit for measuring a quality factor of the resonator based on a measurement of an attenuation of the output signal during a momentary phase of cutoff of the excitation signal E applied to the resonator. This circuit for measuring the quality factor is configured so as to activate the excitation signal cutoff phase, for a duration of cutoff Td such that at the end of the cutoff phase, the peak amplitude of the output signal is attenuated by factor to the nominal peak amplitude A0 at the start of the cutoff phase, by a factor k with 1<k?2.

Abstract: The invention relates to vibrating micro-systems, and notably but not exclusively to pressure, acceleration, or angular speed micro-sensors with a resonator in an evacuated cavity. The resonator (10) with a vibrating element is placed in an oscillating circuit controlled by a closed-loop control, the oscillating circuit supplying an oscillating signal y(t) at a resonance frequency Fp representing the measurement of a physical quantity. The resonance frequency is calculated by counting pulses over a time window. The sensor furthermore comprises means for calculating a continuity parameter Pc representing the variations in the result of the calculation of the resonance frequency over the course of the successive time windows, and means for comparing the parameter Pc with a threshold in order to deduce from this information on the degradation of the precision of the sensor.

Abstract: A micro-system, for example a micro-sensor, comprises a resonator 10 with vibrating element(s) 11 receiving an excitation signal E of a loop 20 for automatic gain control, as a function of an amplitude setpoint (C) and providing as output a signal y(t) defined by a peak amplitude having a nominal value A0 dependent on the said setpoint and a resonant frequency. The micro-sensor integrates a circuit for measuring a quality factor of the resonator based on a measurement of an attenuation of the output signal during a momentary phase of cutoff of the excitation signal E applied to the resonator. This circuit for measuring the quality factor is configured so as to activate the excitation signal cutoff phase, for a duration of cutoff Td such that at the end of the cutoff phase, the peak amplitude of the output signal is attenuated by factor to the nominal peak amplitude A0 at the start of the cutoff phase, by a factor k with 1<k?2.

Abstract: A micromachined accelerometer in a flat plate includes a base and at least two resonator measuring cells provided with a common mobile seismic element, the two measuring cells being placed one on each side of the common mobile seismic element along the sensitive axis of the accelerometer, such that under the effect of an acceleration, the resonator of one measuring cell undergoes a traction while the resonator of the other measuring cell undergoes a compression, the measuring cells respectively configured to amplify the acceleration force generating the translation of the common mobile seismic element provided with a respective anchoring foot-piece. The common mobile seismic element includes at least two mobile seismic masses able to be displaced in translation along the sensitive axis of the accelerometer and/or in rotation with respect to a respective axis of rotation substantially orthogonal to the sensitive axis under the effect of an acceleration along the sensitive axis.

Abstract: An electrostatic device for damping a mechanical vibration movement of a moving object, the moving object being made of an electrically conductive material, the movement of the moving object having at least one parasitic vibration mode of frequency fp to be damped, the device comprising an electrode ELE forming, with the moving object, a gap of capacitance C voltage-biased with a DC voltage V0 by a biasing circuit, the biasing circuit comprising, electrically connected in series with the electrode ELE: a load resistance R; possibly an inductance L; a parasitic capacitance Cp, characterized in that the biasing circuit further includes an electronic compensating device DEC having an impedance Zeq, which comprises a capacitance component Ceq, a resistance component Req, and possibly an inductance component Leq.

Abstract: An electrostatic device for damping a mechanical vibration movement of a moving object, the moving object being made of an electrically conductive material, the movement of the moving object having at least one parasitic vibration mode of frequency fp to be damped, the device comprising an electrode ELE forming, with the moving object, a gap of capacitance C voltage-biased with a DC voltage V0 by a biasing circuit, the biasing circuit comprising, electrically connected in series with the electrode ELE: a load resistance R; possibly an inductance L; a parasitic capacitance Cp, characterized in that the biasing circuit further includes an electronic compensating device DEC having an impedance Zeq, which comprises a capacitance component Ceq, a resistance component Req, and possibly an inductance component Leq.

Abstract: The invention relates to a micromachined accelerometer in a flat plate comprising a base and at least two resonator measuring cells provided with a common mobile seismic element, the two measuring cells being placed one on each side of the common mobile seismic element along the sensitive axis of the accelerometer, such that under the effect of an acceleration, the resonator of one measuring cell undergoes a traction whilst the resonator of the other measuring cell undergoes a compression, said measuring cells respectively comprising means of amplification of the acceleration force generating the translation of the common mobile seismic element provided with a respective anchoring foot-piece.

Abstract: The field of the invention is that of the wiring of electromechanical micro-systems also called MEMS (the acronym standing for Micro Electro Mechanical Systems) and more particularly micro-systems carrying out measurements of physical quantities such as for example micro-gyrometers, micro-accelerometers or pressure micro-sensors. More precisely the subject of the invention is a wiring relay for an electromechanical micro-system enclosed in a protective package. A first end of a wire bond of electrically conducting material is fixed to the micro-system electrical contact. The relay is fixed to at least one internal wall. The relay consists of an electrically insulating material. According to the invention, it comprises tracks of electrically conducting material, and one track is linked electrically with at least one internal electrical contact and with a second end of a wire bond.

Abstract: Accelerometer micromachined in a plane plate comprising a base, and at least one measurement cell including a moveable seismic mass connected to the base and capable of moving translationally along the sensitive y axis of the accelerometer under the effect of an acceleration ? along this y axis, a resonator cell that comprises a resonator that can vibrate and be subjected to a tensile or compressive force depending on the direction of the acceleration ? and is placed symmetrically with respect to an axis of symmetry S of the structure, this axis S being parallel to the y axis and passing through the center of gravity of the seismic mass, the measurement cell furthermore including amplification means for amplifying the acceleration force, which means comprise at least one anchoring foot for anchoring to the base, two rigid terminations of the resonator cell and two pairs of micromachined arms symmetrical with respect to the axis S, each pair comprising a first arm connecting a termination to the seismic mass,

Abstract: Accelerometer micromachined in a plane plate comprising a base, and at least one measurement cell including a moveable seismic mass connected to the base and capable of moving translationally along the sensitive y axis of the accelerometer under the effect of an acceleration ? along this y axis, a resonator cell that comprises a resonator that can vibrate and be subjected to a tensile or compressive force depending on the direction of the acceleration ? and is placed symmetrically with respect to an axis of symmetry S of the structure, this axis S being parallel to the y axis and passing through the center of gravity of the seismic mass, the measurement cell furthermore including amplification means for amplifying the acceleration force, which means comprise at least one anchoring foot for anchoring to the base, two rigid terminations of the resonator cell and two pairs of micromachined arms symmetrical with respect to the axis S, each pair comprising a first arm connecting a termination to the seismic mass,

Abstract: The invention relates to low-frequency underwater detection systems comprising a towed linear antenna (12, 13). It consists in producing the transducers of the transmission antenna (12) in the form of flextensional arrays of cylindrical type (20) and in forming directional transmission channels covering all of space. It makes it possible to lighten the assembly and to facilitate implementation at sea, which becomes able to be automated.

Abstract: The invention relates to low-frequency underwater detection systems comprising a towed linear antenna (12, 13).