Air-coupled ultrasound spectroscopy and its potential application in agro-industry

Collazos-Burbano, David; Ealo, Joao L.; Torres, Gerardo Andrés; Barandica, Asfur; Álvarez-Arenas, Tomás Gómez

doi:10.1109/stsiva.2014.7010158

Cited by 2 publications

(1 citation statement)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A beneficial aspect of NCUS is the contactless nature of the ultrasonic heads and probing objects (Battaglini et al, 2015;Collazos-Burbano et al, 2014). Therefore, the air-coupled NCUS operates accurately on assembly lines where the CUS method is difficult or impossible to apply.…”

Section: Introductionmentioning

confidence: 99%

Elasticity investigation of thin cellular structure films for piezoelectric sensors

Klimiec

Zachariasz

Kaczmarek

et al. 2021

View full text Add to dashboard Cite

Purpose This paper aims to present the details of isotactic polypropylene (it-PP) films with a cellular structure (air-cavities) dedicated to pressure sensors. The polymer composites (thin films enriched with 5 and 10 wt% of mineral fillers as Sillikolloid P 87 and glass beads) should exhibit suitable structural elasticity within specific stress ranges. After the deformation force is removed, the sensor material must completely restore its original shape and size. Design/methodology/approach Estimating the stiffness tensor element (C33) for polymer films (nonpolar space-charge electrets) by broadband resonance ultrasound spectroscopy is a relatively simple method of determining the safe stress range generated in thin pressure sensors. Therefore, ultrasonic and piezoelectric studies were carried out on four composite it-PP films. First, the longitudinal velocity (vL) of ultrasonic waves passing through the it-PP film in the z-direction (thickness) was evaluated from the ω-position of mechanical resonance of the so-called insertion loss function. In turn, the d33 coefficient was calculated from accumulated piezoelectric charge density response to mechanical stress. Findings Research is at an early stage; however, it can be seen that the mechanical orientation of the it-PP film improves its piezoelectric properties. Moreover, the three-year electric charge stability of the it-PP film seems promising. Originality/value Ultrasonic spectroscopy can be successfully handled as a validation method in the small-lot production of polymer films with the air-cavities structure intended for pressure sensors. The structural repeatability of polymer films is strongly related to a homogeneous distribution of the electric charge on the electret surface.

show abstract

Section: Introductionmentioning

confidence: 99%