An angular acceleration sensor includes a planar surface extending along an X-Y plane, a fixed portion, a weight, a beam, and piezoresistors. The weight is supported by the fixed portion. The beam extends along an Y-axis and is connected to the fixed portion and the weight. The beam includes through-holes extending therethrough in a Z-axis direction and protrusions protruding in an X-axis direction. The positions of the piezoresistors in the Y-axis direction overlap those of the through-holes and are displaced from those of the width-direction protrusions.

An accelerometer includes a base, two elastic portions and two masses. The base includes a supporting portion. Each of the elastic portions is connected to the supporting portion. The supporting portion is located between the two masses, the two masses are connected to the two elastic portions respectively, and the base supports the two elastic portions and the two masses merely by the supporting portion. The two masses are adapted to produce movements to enable the two elastic portions to be elastically deformed.

An impact sensor for a vehicle. The impact sensor includes at least one strain-sensitive sensor element which comprises a sensor material, and at least two terminals, between which the sensor material is electrically connected. The sensor material is a metal-containing carbon material.

A device for detecting an acceleration in one direction and a speed of rotation along one direction, including a support and two structures mechanically coupled to each other in opposite phase and suspended relative to the support, each of the structures including: an excitation mass; an excitation mechanism configured to move the excitation mass in a given direction; an inertial mass suspended to the excitation mass; a detector connected to the inertial mass to be displaced by same, and the detector connected to the support; a mechanism for detecting displacement of the inertial mass; and a controller controlling the excitation mechanism and processing signals delivered by the detecting mechanism.

Linear accelerometer comprising a fixed part, a rotationally moving part in the plane of the accelerometer around an axis of rotation orthogonal to the plane of the accelerometer, the moving part comprising a centre of gravity distinct from the point of intersection of the axis of rotation and the plane of the accelerometer, means forming pivot link between the moving part and the fixed part, means for detecting the displacement of the moving part with respect to the fixed part, means for viscous damping the displacement of the moving part in said plane, said viscous damping means comprising interdigitated combs, at least one first comb on the moving part and at least one second comb on the fixed part (2), the first comb and the second comb being interdigitated.

A circuit configured to sense an input analog signal generated by a sensor at a first frequency and to generate an output digital signal indicative of the sensed input analog signal. The circuit includes a conditioning circuit, an ADC, a feedback circuit, and a low-pass filter. The conditioning circuit is configured to receive the input analog signal and to generate a conditioned analog signal. The ADC is configured to provide a converted digital signal based on the conditioned analog signal. The feedback circuit includes a band-pass filter configured to selectively detect a periodic signal at a second frequency higher than the first frequency and to act on the conditioning circuit to counter variations of the periodic signal at the second frequency. The low-pass filter is configured to filter out the periodic signal from the converted digital signal to generate the output digital signal.

Systems and methods for evaluating the performance of an athlete using a strain gauge is described. In some embodiments, the measurement system comprises a strain gauge and a central processing device. The strain gauge can include a power source, an inertial measurement unit (“IMU”) comprising a load cell, a microcontroller, and a wireless communication module. The strain gauge can be configured to output strain data at a rate of at least 1 kHz and the central processing device can be configured to receive the strain data transmitted from the wireless communication module.

A two-wire reference accelerometer includes integrated mechanical transducing and self-calibration capability based on gravity only. The reference accelerometer includes an external two-wire connector and an internal three-wire transducer that responds to both steady-state acceleration and time-varying accelerations by producing a modulated transducer output signal having a steady-state waveform when the transducer senses steady state acceleration and a time-varying waveform when the transducer senses time-varying accelerations. A signal conditioning circuit conditions the transducer output signal and applies it to the two-wire electrical connector as a modulated reference accelerometer output signal. The transducer and the signal conditioning circuit can operate without modification in either a DUT calibration mode or a self-calibration mode. The self-calibration mode determines the 1 g output sensitivity of the reference accelerometer from first and second readings of the reference accelerometer output signal taken while the reference accelerometer rests on a non-accelerating surface in respective non-inverted and inverted orientations.

A sensor includes a plurality of piezoresistive elements and a plurality of electrical connection terminals. The plurality of piezoresistive elements are fabricated on a first side of a substrate. A second side of the substrate is configured to be coupled to an object where a physical disturbance is to be detected. A plurality of electrical connection terminals are coupled to the first side of the substrate.

A piezoelectric sensor comprises a support structure, a channel extending through the support structure, a sensing material stack coupled to the support structure and extending over the channel, and a filler material disposed within the channel and over the sensing material stack. The sensing material stack comprises an structural layer, a first electrode layer disposed on the structural layer, a piezoelectric material disposed in a piezoelectric layer on the first electrode, and a second electrode disposed on the piezoelectric layer opposite the first electrode layer.