Sensing piezoelectric

Giurgiutiu V, Zagrai AN. Embedded self-sensing piezoelectric active sensors for on-line structural identification. J Vib Acoust Trans ASME 2002 124(1) 116—25. http //dx.doi.org/10.1115/1.1421056. 

The tube is created with a squared cross section, 10 pm wide. The driver and driven section have equal lengths. The driver and driven sections are separated by a membrane, and the test section is prefilled with the test gas during fabrication. The top side of the tube is made of a plate comprising direct-sensing piezoelectric gauges, used for timing the arrival of pressure waves. 

Dosch, J. J. Inman, D.J. Garcia, E. A self-sensing piezoelectric actuator for collocated control. J. Intell. Mater. Syst. and Struct., 3 (1992), pp. 166 185 Vallone, P. High-performance piezo-based self-sensor for structural vibration control. SPIE Smart Structures and Mater. Conf., 2443, SPIE (1995), pp. 643 655... 

Bulk-wave piezoelectric quartz crystal sensors indirecdy measure mass changes of the coating on the surface of the sensing device. This change in mass causes changes in the resonant frequency of the device, and measurements ate based on frequency differences. 

Depth-sensing nanoindentation is one of the primary tools for nanomechanical mechanical properties measurements. Major advantages to this technique over AFM include (1) simultaneous measurement of force and displacement (2) perpendicular tip-sample approach and (3) well-modeled mechanics for dynamic measurements. Also, the ability to quantitatively infer contact area during force-displacement measurements provides a very useful approach to explore adhesion mechanics and models. Disadvantages relative to AFM include lower force resolution, as well as far lower spatial resolution, both from the larger tip radii employed and a lack of sample positioning and imaging capabilities provided by piezoelectric scanners. 

The information presented in this work builds upon developments from several more established fields of science. This situation can cause confusion as to the use of established sign conventions for stress, pressure, strain and compression. In this book, those treatments involving higher-order, elastic, piezoelectric and dielectric behaviors use the established sign conventions of tension chosen to be positive. In other areas, compression is taken as positive, in accordance with high pressure practice. Although offensive to a well structured sense of theory, the various sign conventions used in different sections of the book are not expected to cause confusion in any particular situation. 

The basic idea of AFM is to use a sharp tip scanning over the surface of a sample while sensing the interaction between the tip and the sample (Dufrene, 2008b). The tip with a flexible cantilever (in some AFM models the sample) is mounted on a piezoelectric scanner which can move... 

Piezoelectric ceramics, which depend on lead compounds, are used to produce transducers and sensors which make possible ultrasound technologies used in wide-ranging medical and commercial applications, guidance and sensing systems used in defense and commerce, and in addition, new "smart materials" research projects. 

A piezoelectric-sound-resonance cavity (PSRC) has been used as a sensing element for hydrogen [39]. The sensing mechanism was based on the acoustic property differences... 

An altemahve approach is the "mass-sensing" multianalyte microarray immunoassay first described by researchers at Beckman Coulter, Fullerton, CA (Silzel et al., 1998). As early as 1991, other groups at Beckman Coulter had adapted commercially available ink-jet printers (e.g., the Hewlett Packard Deskjet) for deposihng oligonucleohdes or proteins such as streptavidin onto substrates to create arrays (Matson, xmpublished data). Piezoelectric... 

Non-labelled immunosensors rely on various principles (Fig. 3.27.A). Either the antibody or the antigen is immobilized on the solid matrix to form a sensing device. The solid matrix should be sensitive enough at the surface to detect immunocomplex formation. Electrode, membrane, piezoelectric and optically active surfaces may in principle be used to construct non-labelled immunosensors. The antigen or antibody to be determined is dissolved in a solution and reacted with the complementary matrix-bound antibody or antigen to form an immunocomplex that alters the physical e.g. the electrode potential or intrinsic piezofrequency) or optical properties of the... 

In the contact mode the tip scans the sample in close contact with the surface. The force on the tip is repulsive with a mean value of 10 N. This force is set by pushing the cantilever against the sample surface with a piezoelectric positioning element. In contact mode AFM the deflection of the cantilever is sensed and compared in a DC feedback amplifier to some desired value of deflection. If the measured deflection is different from the desired value, the feedback amplifier applies a voltage to the piezo to raise or lower the sample relative to the cantilever in order to restore the desired value of deflection. The voltage that the feedback amplifier applies to the piezo is a measure of the height of features on the sample surface. It is displayed as a function of the lateral position of the sample. 

Electric sensing devices (strain gauges, piezoresistive transducers, and piezoelectric transducers)... 

Angular displacement sensed by piezoelectric accelerometers frequency from vibrator input G M G M... 

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