Apparatus and associated methods relate to maximizing a signal to noise ratio of an accelerometer by inhibiting signals arising from movements of a proofmass in directions perpendicular to a direction of intended sensitivity. The direction of intended sensitivity of the accelerometer is along an axis of the proofmass. The accelerometer is rendered substantially insensitive to lateral accelerations of the proofmass by making the accelerometer axially symmetric. Two axially-asymmetric acceleration sensing devices are axially engaged in such a manner as to render the coupled sensing devices substantially axially-symmetric. In some embodiments, each acceleration sensor has an axially-thin membrane portion extending from a proofmass portion. The two acceleration sensors can be engaged in an antiparallel fashion at projecting ends of the proofmass portions. An engagement surface will be located about halfway between the axially-thin membrane portions of the two acceleration sensors, thereby causing mechanical symmetry about the engagement surface.

Methods are described for constructing a mechanical resonating structure by applying an active layer on a surface of a compensating structure. The compensating structure comprises one or more materials having an adaptive resistance to deform that reduces a variance in a resonating frequency of the mechanical resonating structure, wherein at least the active layer and the compensating structure form a mechanical resonating structure having a plurality of layers of materials A thickness of each of the plurality of layers of materials results in a plurality of thickness ratios therebetween.

A pair of vector sensors are provided and mounted orthogonally to each other. Each vector sensor includes a central structural member having a first end and a second end. The central structural member has four symmetric arms oriented at 90° to each other. A crystalline plate is attached perpendicular to a distal end of each arm of the central structural member. The first end of each vector sensor is embedded in a socket of a proof mass. The second end of each vector sensor is embedded in an aperture of a cubic base.

An object of the present invention is to provide a vibration sensor in which the frequency dependence of the output is small. The present invention provides a vibration sensor 1 comprising: a support 2; an organic piezoelectric material 3 deformably disposed in or on the support 2; and an electrode 4 for extracting an electrical signal generated by deformation of the organic piezoelectric material 3, the electrode 4 being formed on the organic piezoelectric material 3, the organic piezoelectric material 3 comprising a copolymer of vinylidene fluoride and one or more monomers copolymerizable with vinylidene fluoride.

Apparatus and techniques are disclosed relating to sensor housing and spacer carrier assemblies. In various embodiments, a spacer carrier provides a cavity through a body of the spacer carrier and a first alignment element positioned at a first end of the cavity. In some embodiments, a sensor housing is configured to be deployed within the cavity through the body of the spacer carrier. The sensor housing may include a housing body configured to receive a sensor and a second alignment element configured to interface with the first alignment element. In various embodiments, the first and second alignment elements are configured to maintain an orientation of the sensor housing within the cavity when the sensor housing is inserted into the spacer carrier.

A vehicle control apparatus according to an embodiment of the present technology includes a control unit. The control unit generates a control signal for controlling behavior of a vehicle body on a basis of a first acceleration detection signal and a second acceleration detection signal, the first acceleration detection signal including information relating to an acceleration acting on the vehicle body, the first acceleration detection signal having an alternating current waveform corresponding to the acceleration, the second acceleration detection signal including information relating to the acceleration, the second acceleration detection signal having an output waveform, an alternating current component corresponding to the acceleration being superimposed on a direct current component in the output waveform.

The disclosure provides a piezoelectric acceleration sensor including a charge output element, a casing, a cable assembly and a connector. The casing is snap-fitted to a supporting portion of a base of the charge output element, and forms a receiving space for receiving the charge output element, the piezoelectric, and the mass block with the supporting portion. The cable assembly is connected to the supporting portion. The connector is connected to an end of the cable assembly facing away from the supporting portion, and is insulated from the cable assembly. One end of either of a first lead and a second lead of the cable assembly is electrically connected to the piezoelectric element, while the other end of the first lead is electrically connected to a conductive terminal of the connector and the other end of the second lead is electrically connected to a housing of the connector.

A sensor unit includes: a substrate; a first sensor module that is disposed at the substrate and that includes a first acceleration sensor; and a second sensor module that is disposed at the substrate and includes a second acceleration sensor, in which the first sensor module and the second sensor module are arranged to be adjacent to each other at one surface side of the substrate, the first acceleration sensor is eccentrically disposed at the second sensor module side in the first sensor module, and the second acceleration sensor is eccentrically disposed at the first sensor module side in the second sensor module.

A seismic survey apparatus includes a body having a longitudinal axis, a first end, a second end opposite the first end, and an inner cavity positioned between the first end and the second end. In addition, the seismic survey apparatus includes a proof mass moveably disposed in the inner cavity of the body. The proof mass is configured to move axially relative to the body. Further, the seismic survey apparatus includes a first sensor disposed in the inner cavity. The first sensor comprises a first piezoelectric element configured to detect the axial movement of the proof mass relative to the body. Still further, the seismic survey apparatus includes electronic circuitry coupled to the first piezoelectric element. The electronic circuitry is configured to receive and process an output of the first piezoelectric element. The proof mass comprises a power supply configured to provide electrical power to the electronic circuitry.

Wireless piezoelectric accelerometers and systems are provided. A wireless piezoelectric accelerometer may comprise a piezoelectric sensing element configured to sense mechanical acceleration and produce an electrical charge signal in response of the sensed mechanical acceleration, a signal processing module (SPM) configured to convert the electrical charge signal into a voltage signal, and process and digitize the voltage signal, and a wireless module configured to modulate and transmit the digitized voltage signal as wireless signals. The piezoelectric sensing element, the SPM and the wireless module are packaged in a casing. The casing comprises a metallic shielding chamber configured to enclose the piezoelectric sensing element. The casing further comprises a non-metallic portion located in relative to the wireless module to allow transmission of the wireless signals. Corresponding wireless piezoelectric accelerometer systems are also provided.