Abstract: A method for measuring positional changes of an object, including rotation about any or all of three axes, using linear accelerometers. There is disclosed a method of using a linear accelerometer to integrate two other 3D linear accelerometers in order to measure and supply for further use six-dimensional information, that is, translation in three dimensions and rotation about three axes. Two linear accelerometer sensors are used to determine all but one of the variables in the six degrees of freedom. Output from a third accelerometer generates the data need to determine a sixth, rotational, degree of freedom. The need for a gyroscope for detecting changes in heading (i.e., yaw or azimuth) may therefore be avoided.

Abstract: A sensor unit has a reference base. An acceleration sensor block and angular velocity sensor support rods are arranged on the reference base, using a bottom face and one side face of the reference base as reference faces. Three acceleration sensors, which detect accelerations that act in the directions in which an X-axis, a Y-axis, and a Z-axis extend, are fitted to three faces of the acceleration sensor block, respectively. Three angular velocity sensors, which detect angular velocities about the X-axis, the Y-axis, and the Z-axis, are fitted to boards that are fitted, via rubber bushings serving as vibration-proofing rubber members, to the angular velocity sensor support rods with screws, respectively.

Abstract: The invention relates to a system for accelerating moving bodies. The inventive system is characterised in that it comprises the simultaneous application of two torques which are perpendicular to one another and which are perpendicular to the induced or intrinsic angular momentum of the device.

Abstract: An inertial system is provided. The system includes at least one inertial sensor, a processing unit and a plurality of Kalman filters implemented in the processing unit. The Kalman filters receive information from the at least one inertial sensor, and at most one of the plurality of Kalman filters has processed zero velocity updates on the last cycle. The plurality of Kalman filters is used to optimize system response and performance during periods of intermittent motion.

Abstract: A gyro module includes: two gyro element pieces outputting a signal, the signal being obtained by combining a signal of an angular velocity of a first detection axis and a signal of an angular velocity of a second detection axis; and an arithmetic circuit for performing an addition and a subtraction with respect to the signal outputted from the two gyro element pieces. The two gyro element pieces are a first gyro element piece and a second gyro element piece. The first and second gyro element pieces are arranged such that a detection sensitivity polarity of the first detection axis of the first gyro element piece is same as that of the second gyro element piece, and a detection sensitivity polarity of the second detection axis of the first gyro element piece and that of the second gyro element piece are inverted.

Abstract: An activity monitor is provided that reduces the amount of power consumed during a monitoring operation.

Abstract: The present invention relates to an electric device, which comprises: a micro inertial sensing module, for detecting a motion of the electric device with respect to the degree of freedom of six axes and thus issuing a sensing signal basing on the detection; a sensing signal processor, for receiving and processing the sensing signal to form a system processing signal; and a display; wherein the displacements and rotations of the motion detection-enabled electric device is sensed and measured by the micro inertial sensing module for enabling the micro inertial sensing module to generate sensing signals corresponding thereto and thus sending the same to the sensing signal processor for processing, and then the result of the processing is adopted as the input of the motion detection-enabled electric device for causing the motion detection-enabled electric device to response in the display accordingly.

Abstract: The present invention features a system and method for estimating body states of a vehicle. The system includes at least two sensors mounted to the vehicle. The sensors generate measured vehicle state signals corresponding to the dynamics of the vehicle. A signal adjuster transforms the measured vehicle states from a sensor coordinate system to a body coordinate system associated with the vehicle. A filter receives the transformed measured vehicle states from the signal adjuster and processes the measured signals into state estimates of the vehicle, such as, for example, the lateral velocity, yaw rate, roll angle, and roll rate of the vehicle.

Abstract: A system for estimating motion parameters corresponding to a user. The system may generally include a receiver operable to receive a signal from an external source, an inertial sensor operable to be coupled with the user and arbitrarily oriented relative to the direction of user motion for generation of a signal corresponding to user motion, and a processing system in communication with the receiver and inertial sensor.

Abstract: A gyro-module includes: a first gyro element component having a first detection axis and a second detection axis, and outputting at least a signal that is based on angular velocity around the first detection axis and the second detection axis; a second gyro element component having a first detection axis and a second detection axis, and outputting at least a signal that is based on angular velocity around the first detection axis and the second detection axis; a third gyro element component having a first detection axis; a first operation circuit conducting an operation of an output signal from the first gyro element component and an output signal from the third gyro element component; and a second operation circuit conducting an operation of an output signal from the second gyro element component and an output signal from the third gyro element component.

Abstract: The present invention is related to sensor arrangements and particularly to sensor arrangements for symmetric response in a x-, y- and z-coordinate system. The arrangement comprises four gyroscopes with one axis arranged into different directions of sensitivity.

Abstract: A mobile navigation system gyro module comprises: first and second gyro sensors outputting angular velocities ?1, ?2 around first and second axes intersecting at an acute angle ?12; a sign determination circuit determining a sign of ?1; a correction circuit correcting the first and second gyro sensor outputs; and a computation circuit computing ??=?(?1?2+SA2) and SA=(?2???1? cos ?12)/sin ?12 using angular velocities ?1?, ?2? from the correction circuit, and outputting angular velocity ? by multiplying ?? by the sign of ?1, wherein the correction circuit includes: first and second offset adjustment circuits outputting ?1? and ?2? by respectively subtracting from ?1 and ?2, corrections B1 and B2 corresponding to the first and second gyro sensor outputs when the mobile unit stops; and the angular velocity ? is around an axis coplanar with and between the first and second axes.

Abstract: A three-axis MEMS transducer featuring a caddie-corner proof mass comprises a planar main body portion of conductive material and a planar extra mass caddie-corner feature. The main body portion includes a width, length, and at least four side edges. An x-axis sense direction is defined from a first side edge to an opposite first side edge and a y-axis sense direction is defined from a second side edge to an opposite second side edge. The x-axis sense direction is perpendicular to the y-axis sense direction. The main body portion further includes at least two corners. The caddie-corner feature is positioned about at least one of the two corners of the main body portion. The caddie-corner feature and the main body portion comprise a single proof mass having a z-sense pivot axis disposed at an angle of ninety degrees to a diagonal extending from the caddie-corner feature to an opposite corner of the main body portion.

Abstract: A patch for detecting movements of a body and its use.

Abstract: Apparatus, methods, and systems for sensing acceleration and magnetic fields in all three axes from a first capacitive bridge sensor having a first proof mass; and a second capacitive bridge sensor having a second proof mass located within the first proof mass. The second proof mass is coupled to the first proof mass by springs that permit movement in the second axis. Sensing of the remaining axis of interest may be done by a third and fourth capacitive bridge configured similar to that of the first and second capacitive bridge sensors. The third and fourth capacitive bridge sensors may be oriented 90 degrees off of the first and second capacitive bridge. An alternative is to locate a third capacitive bridge within the second proof mass.

Abstract: A traveling apparatus is provided with two wheels parallel each of which is driven independently, being controlled to be stable in an anteroposterior direction between the two wheels and traveling. The traveling apparatus includes a mechanism estimating an inclination of a plane where a pitch angular velocity sensor is horizontally installed with respect to a horizontal plane by using a sensor measuring a tilt of a vehicle body in a roll axis direction and a mechanism calculating a correct pitch angle by obtaining a yaw rate mixed in the pitch angular velocity sensor based on the estimated inclination and a turn velocity of the vehicle body and by canceling the yaw rate mixed.

Abstract: A transducer package 20 includes a substrate 32 having a first axis of symmetry 36 and a second axis of symmetry 38 arranged orthogonal to the first axis of symmetry 36. At least a first sensor 50 and a second sensor 52 each of which are symmetrically arranged on the substrate 32 relative to one of the first and second axes of symmetry 36 and 38.The first and second sensors 50 and 52 are adapted to detect movement parallel to the other of the first and second axes of symmetry 36 and 38. The first sensor 50 is adapted to detect movement over a first sensing range and the second sensor 52 is adapted to detect movement over a second sensing range, the second sensing range differing from the first sensing range.

Abstract: An input device includes a main body and a motion sensor unit. The main body has a longitudinal axis. The motion sensor unit is configured and arranged to detect rotation of the main body about the longitudinal axis. The motion sensor unit has an X-axis angular velocity sensor configured and arranged to detect an angular velocity of the main body about an X-axis in a three-dimensional orthogonal coordinate system defined by the X-axis, a Y-axis and a Z-axis. The X-axis coincides with the longitudinal axis of the main body and the Y-axis and the Z-axis being orthogonal to each other in a first plane perpendicular to the X-axis.

Abstract: An acceleration sensor of the present invention is a heat sensing type acceleration sensor, and includes a heating chip formed with a heating element on a surface thereof, and a sensor chip formed with a thermocouple element on a surface thereof and disposed so that the surface faces the surface of the heating chip.

Abstract: A fall detecting method and a device for detecting a fall with high accuracy even when an object touches a human or a thing while falling. The fall detecting device has an output detecting part for generating an acceleration detection output after comparing the magnitude of acceleration detected by a three-axis acceleration sensor with a certain threshold, an output interruption correcting part for generating an output interruption corrected acceleration output which is corrected for an interruption when a fall acceleration output recovers within a first predetermined time after the fall acceleration output interrupts, and an output continuation time judging part for generating a fall judgment output when the output interruption corrected acceleration output continues for a second predetermined time longer than the first predetermined time.

Abstract: The present invention relates to measuring devices used in measuring physical quantities, such as acceleration, angular acceleration, or angular velocity, and, more precisely, to micromechanical motion sensors. The area, in the wafer plane, of a motion sensor component according to the present invention is smaller than the area of the motion sensor component having been dice cut and turned by 90°. Correspondingly, the height of the motion sensor component according to the present invention, the component having been turned by 90°, is smaller, in the direction of the joint, than the thickness of the wafer stack formed by the joined wafers. The object of the invention is to provide an improved method of manufacturing a micromechanical motion sensor, and to provide a micromechanical motion sensor suitable, in particular, for use in small micromechanical motion sensor solutions.

Abstract: An apparatus for measuring activity of a test subject includes a buckle configured to engage with a belt strap to form a belt that is securable around a body portion of the test subject, and an activity measuring device secured to the buckle so as to facilitate recording activities of a test subject, the activity measuring device including at least one acceleration sensor configured to detect acceleration in all three spatial directions at right angles to each other.

Abstract: In an acceleration sensor, a first vibrator is arranged on a surface of a substrate such that the vibrator can vibrate in an X-axis direction. An angular-velocity-detecting vibrator is arranged inside the first vibrator such that the vibrator can be displaced in a Y-axis direction. A vibration generating unit and a vibration monitor unit are provided between the substrate and the first vibrator. An angular-velocity-detecting displacement detecting unit is provided between the substrate and the angular-velocity-detecting vibrator. A second vibrator is provided outside the first vibrator such that the vibrator can be displaced in the Y-axis direction. An acceleration-detecting displacement detecting unit is provided between the first and second vibrators. An angular velocity detecting circuit detects angular velocity by performing synchronous detection on a displacement detection signal from the displacement detecting unit using a monitor signal from the vibration monitor unit.

Abstract: The present invention relates to a system and method for measurement of flow velocity using the transmission of a sequence of coherent pulsed ultrasonic signals into the flow, and sampling the received response signal at a predetermined delay time relative to the pulse transmission that does not correspond to the signal transmission time. The sampling may be coherent with a frequency offset from the coherency frequency of the pulses. The received signal samples are then spectrally processed, typically by a Fourier process, to generate a frequency domain data set. A threshold technique is used on the frequency domain data set to determine a peak Doppler shift. Average velocity is then obtained by multiplying the peak Doppler shift by a factor, for example, 0.90. In one embodiment, the transmit pulse and receive samples are interleaved by alternating between transmitting a pulse and, after a delay, sampling the received signal.

Abstract: An acceleration sensor includes a substrate, a rocker mass, a z spring connected to the rocker mass, which allows the rocker mass to rotate about an axis, and at least one additional spring system connected to the substrate and the rocker mass. The additional spring system allows the rocker mass to deflect in an x or y direction oriented parallel or perpendicular to the axis. The z spring or the additional spring system allows the rocker mass to deflect in a y or x direction oriented parallel or perpendicular to the axis.

Abstract: An apparatus for monitoring the rotational speed in a wind energy plant, with a rotor shaft which is driven by the rotor and runs out into a gear unit, and with a generator shaft, which connects an output shaft of the gear unit with a generator/converter unit, characterized by a first rotational speed detection unit on the rotor shaft and a second rotational speed detection unit on the generator shaft, wherein each rotational speed detection unit has at least two rotational speed sensors working independently from each other, an analyzing unit for the rotational speed, to which the measured signals of the rotational speed detection units are applied and which generates an error signal for a rotational overspeed when a certain maximum value for the rotational speed is exceeded.

Abstract: In a method for determining the relative position, velocity, acceleration, and/or the rotation center of a body displaceable in a three dimensional space, at least twelve linear acceleration sensors are provided and in each case arranged on a position which is stationarily fixed with respect to the body. At least one acceleration measurement signal is captured by the linear acceleration sensors. A position, velocity, acceleration, and/or rotation center signal is generated for the body from the acceleration measurement signal and data describing the position and orientation of the linear acceleration sensors in the body-fixed coordinate system.

Abstract: An activity measuring device (1) is used for recording the activity of a test subject, where the device (1) is attachable so as to be carried on the body of the test subject. According to the invention it is planned that the activity measuring device is located on a buckle (2) of a belt (3) which can be fitted to the body of the test subject, and that it has acceleration sensors (10, 10?) for detection of acceleration in all three spatial directions at right angles to each other. Furthermore, the activity measuring device (1) telemeters the recorded measurement data via a radio link to a central server (7), by virtue of the fact that the measurement data recorded by the activity measuring device (1) can be transmitted by means of a connecting cable (5) to a mobile telephone (4) via a device interface of the mobile telephone (4), which is arranged so as to be carried on the belt, and can be sent from there to the external server (7) via a radio link.

Abstract: Systems and methods for closed-loop feedback control of controllable devices using motion capture systems are disclosed. In one embodiment, a system includes a motion capture system configured to measure one or more motion characteristics of one or more controllable devices as the one or more controllable devices are operating within a control volume. A processor receives the measured motion characteristics from the motion capture system and determines a control signal based on the measured motion characteristics. A position control system receives the control signal and continuously adjusts at least one motion characteristic of the one or more controllable devices in order to maintain or achieve a desired motion state. The controllable device may be equipped with passive retro-reflective markers. The motion capture system, the processor, and the position control system comprise a complete closed-loop feedback control system.

Abstract: An acceleration sensor includes a base having an XY-substrate surface which is parallel to an XY plane, a beam portion having a frame shape which is arranged in a floating state above the XY-substrate surface of the base, a beam-supporting fixed portion which supports the beam on the base via supporting units like a beam supported by its both ends, weight portions 7 which are arranged so as to float above the XY-substrate surface of the base, and connecting portions which support the weight portions 7 to the beam portion in a cantilever manner. The weight portions are displaceable in the X-axis direction, the Y-axis direction, and the Z-axis direction by the bending deformation of the frame-shaped beam portion. The beam portion is provided with an X-axis direction acceleration detecting portion, a Y-axis direction acceleration detecting portion, and a Z-axis direction acceleration detecting portion.

Abstract: An apparatus for measuring a closing velocity of a door of a vehicle having a body is provided. The apparatus includes a base, a door-closing member, an actuator, and a sensor assembly. The door-closing member is movably coupled to the base. The actuator is coupled to the base and the door-closing member and is configured to move the door-closing member. The movement of the door-closing member causes the door of the vehicle to move relative to the body of the vehicle at a predetermined velocity. The sensor assembly is coupled to the base and configured to detect a position of the door of the vehicle relative to a selected portion of the vehicle and generate a signal representative thereof.

Abstract: A gyroscope for detecting rotation about a gyro input axis, having a support structure, at least one mass flexibly coupled to the support structure such that it is capable of motion in two directions along a drive axis, the mass offset from the gyro output axis, one or more drives for oscillating the flexibly-coupled masses along the drive axis, one or more mass motion sensors that sense motion of the flexibly-coupled masses along their drive axes, and one or more gyro output sensors that detect rotation of the support structure about the output axis.

Abstract: An angular velocity sensor structure for improving the off-axis sensitivity is provided in which a structure for detecting an off-axis acceleration component applied to the angular velocity sensor structure is directly adapted to the sensor structure, thereby measuring the off-axis acceleration component actually applied to the sensor structure without distortion.

Abstract: An example geolocation system for mounting on a mammal incorporates simple sensing sleeves on the calves of the body support members, combined with an accelerometer based gravity direction and force sensing at the center of mass of the body. The example system is connected to a digital processing unit and a battery power supply to integrate the sensing to determine kinetic and potential energy of the body locomotion over time in a method that integrates out the aperiodic motion of the body about the center of mass, and uses the residual motion to measure the center of mass locomotion from a known point.

Abstract: A gravity gradiometer is disclosed which has a sensor in the form of bars (41 and 42) which are supported on a mounting (5) which has a first mount section (10) and a second mount section (20). A first flexure web (33) pivotally couples the first and second mount sections about a first axis. The second mount has a first part (25), a second part (26) and a third part (27). The parts (25 and 26) are connected by a second flexure web (37) and the parts (26 and 27) are connected by a third flexure web (35). The bars (41 and 42) are located in housings (45 and 47) and form a monolithic structure with the housings (45 and 47) respectively. The housings (45 and 47) are connected to opposite sides of the second mount section 20. The bars (41 and 42) are connected to their respective housings by flexure webs (59). Transducers (71) are located in proximity to the bars for detecting movement of the bars to in turn enable the gravitational gradient tensor to be measured.

Abstract: The invention relates to accelerometer structures micro-machined according to micro-electronics technologies. The accelerometer according to the invention comprises a substrate, an elastically deformable thin-layer membrane suspended above the substrate and secured to the substrate at its periphery, a proof mass suspended above the membrane and linked to the latter by a central stud, and capacitive interdigitated combs distributed about the mass, having movable plates secured to the mass and fixed plates secured to the substrate. The fixed plates and movable plates of the various combs are of differentiated heights to help in the discrimination of the upward and downward vertical accelerations.

Abstract: A method for measuring positional changes of an object, including rotation about any or all of three axes, using linear accelerometers. There is disclosed a method of using a linear accelerometer to integrate two other 3D linear accelerometers in order to measure and supply for further use six-dimensional information, that is, translation in three dimensions and rotation about three axes. Two linear accelerometer sensors are used to determine all but one of the variables in the six degrees of freedom. Output from a third accelerometer generates the data need to determine a sixth, rotational, degree of freedom. The need for a gyroscope for detecting changes in heading (i.e., yaw or azimuth) may therefore be avoided.

Abstract: The shock isolation system for an inertial sensor arrangement, on the one hand, causes an advantageous moment of inertia by the special arrangement of the individual sensors, especially of the gyroscope used. On the other hand, an advantageous long interval of the required shock-absorbing components (“shock mounts”) is provided by the use of several tubular shells. A measurement device with this inertial sensor arrangement thus achieves improved accuracy and reliability.

Abstract: One embodiment of the present application includes a multisensor assembly. This assembly has an electromechanical motion sensor member defined with one wafer layer, a first sensor carried with a first one or two or more other wafer layers, and a second sensor carried with a second one of the other wafer layers. The one wafer layer is positioned between the other wafer layers to correspondingly enclose the sensor member within a cavity of the assembly.

Abstract: An acceleration sensor includes a frame-shaped beam portion disposed above an XY substrate surface of a base in a floating state and a beam-portion supporting/fixing unit arranged to attach the beam portion to the base with support portions so as to be supported on two sides. The acceleration sensor also includes weight portions disposed above the XY substrate surface of the base in a floating state and connecting portions for attaching the weight portions to the beam portion in a cantilever state. The weight portions are movable in three axial directions including an X-axis direction, a Y-axis direction, and a Z-axis direction when the beam portion is deflected.

Abstract: An apparatus for monitoring the rotational speed in a wind energy plant, with a rotor shaft which is driven by the rotor and runs out into a gear unit, and with a generator shaft, which connects an output shaft of the gear unit with a generator/converter unit, characterised by a first rotational speed detection unit on the rotor shaft and a second rotational speed detection unit on the generator shaft, wherein each rotational speed detection unit has at least two rotational speed sensors working independently from each other, an analysing unit for the rotational speed, to which the measured signals of the rotational speed detection units are applied and which generates an error signal for a rotational overspeed when a certain maximum value for the rotational speed is exceeded.

Abstract: Provided is an apparatus for measuring acceleration and a tilt angle using thermal convection of a fluid which includes a container containing the fluid, a heating body including a first heating element and a second heating element arranged in the container and a crosspoint that is formed as end portions of the first and second heating elements are electrically connected, and radiating heat when current is applied through the other end portions of the first and second heating elements, and a thermocouple including a thermocouple junction that contacts the crosspoint of the heating body and being point-symmetric with the heating body with respect to the crosspoint of the heating body, wherein a voltage between both end portions of the thermocouple is measured to calculate a temperature of the crosspoint of the heating body.

Abstract: An angular velocity measuring device includes an angular having a mounting surface on which a velocity detection element, element-side drive electrodes and element-side detection electrodes are provided and a ground electrode is disposed between the drive electrodes and the detection electrodes. On the top surface of a multilayer substrate, substrate-side drive electrodes and substrate-side detection electrodes are provided and a ground electrode is disposed between the drive electrodes and the detection electrodes. The electrodes of the angular velocity detection element are connected to the electrodes of the multilayer substrate and the two ground electrodes are arranged to face each other. Furthermore, on the top surface of the multilayer substrate, drive wirings connected to the drive electrodes are provided and, inside the multilayer substrate, detection wirings connected to the detection electrodes are provided.

Abstract: A three-axis MEMS transducer featuring a caddie-corner proof mass comprises a planar main body portion of conductive material and a planar extra mass caddie-corner feature. The main body portion includes a width, length, and at least four side edges. An x-axis sense direction is defined from a first side edge to an opposite first side edge and a y-axis sense direction is defined from a second side edge to an opposite second side edge. The x-axis sense direction is perpendicular to the y-axis sense direction. The main body portion further includes at least two corners. The caddie-corner feature is positioned about at least one of the two corners of the main body portion. The caddie-corner feature and the main body portion comprise a single proof mass having a z-sense pivot axis disposed at an angle of ninety degrees to a diagonal extending from the caddie-corner feature to an opposite corner of the main body portion.

Abstract: A nanomechanical (NEMS) gyroscope includes an integrated circuit substrate, a pair of spaced apart contact pads disposed on the substrate, and a movable nanoscale element forming at least a portion of a first electrically conductive path electrically coupling the contact pads. The movable element experiences movement comprising rotation, changes in rotation, or oscillation upon the gyroscope experiencing angular velocity or angular acceleration. Movement of the gyro introduces geometrically induced phase changes which results in phase and/or frequency changes in ac current flowing through the movable element. An inertial measurement unit (IMU) can include an integrated circuit substrate having a three axis gyroscope formed on the substrate and a three axis accelerometer, which is preferably formed on the same substrate.

Abstract: A free fall detection device capable of detecting a fall accompanied by rotation is provided. A fall accompanied by rotation is detected based on a waveform of an acceleration signal output from the acceleration detection unit and an angular velocity signal output from the angular velocity detection unit. A gravity center acceleration of the device to be protected is calculated from the acceleration detected by the acceleration detection unit and from the angular velocity detected by the angular velocity detection unit. Even when the device being protected rotates as it falls, the fall of the device can be detected from the detected acceleration or angular velocity. Further, by calculating the gravity center acceleration not affected by the rotation, it is possible to detect a fall of the device with high precision even if the device rotates as it falls.

Abstract: Devices for providing tri-axial measurements in an x-direction, a y-direction, and a z-direction and methods of their manufacture are disclosed. The devices comprise a leadframe, at least one X- and Y-axis sensor die, at least one integrated circuit, and a Z-axis sensor. The Z-axis sensor is encapsulated in a pre-molding before the leadframe, X- and Y-axis sensor die(s), integrated circuit(s), and the pre-molding are encapsulated to provide a final molding.

Abstract: A method for measuring positional changes of an object, including rotation about any or all of three axes, using linear accelerometers. There is disclosed a method of using a linear accelerometer to integrate two other 3D linear accelerometers in order to measure and supply for further use six-dimensional information, that is, translation in three dimensions and rotation about three axes. Two linear accelerometer sensors are used to determine all but one of the variables in the six degrees of freedom. Output from a third accelerometer generates the data need to determine a sixth, rotational, degree of freedom. The need for a gyroscope for detecting changes in heading (i.e., yaw of azimuth) may therefore be avoided.

Abstract: The present invention relates to detecting breakage of a shaft of a turbomachine, in particular of the aviation type. The invention relates in particular to a device designed to perform such detection. According to the invention, the device for detecting breakage of a turbomachine shaft comprises: a shaft having an upstream end and a downstream end; a rod having an upstream end and a downstream end, and placed coaxially inside the shaft, the downstream end of the rod being securely fastened to the downstream end of the shaft and the upstream end of the rod being free to rotate relative to the upstream and of the shaft; and a sensor suitable for detecting a difference in speed of rotation between the upstream end of the rod and the upstream end of the shaft.

Abstract: A sensor unit for a three-axis accelerometer enabling reduction in chip size. The sensor unit is connected to an accelerometer that detects a plurality of acceleration values for a plurality of axis directions. The sensor unit includes a correction value generation circuit that sequentially generates a plurality of correction values for correcting the plurality of acceleration values. A correction circuit is connected to the correction value generation circuit to sequentially correct the plurality of acceleration values with a plurality of correction values and generate a plurality of corrected acceleration values.