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This paper presents the development and normalization of a novel sensor system built with low-cost industrial-grade multilayer ceramic capacitors (MLCC). MLCCs play both the roles of force sensing elements and force sustaining elements. With adopting this low-cost industrial component of MLCC (less than 1 cent USD for a sensing component), the time and the cost for producing a high performance force sensor system can be achieved. Practically, industrial-grade MLCCs are produced for capacitor applications but not for a sensing element for force measurement. However, the sensitivity for each independent MLCC presents a large variation for force sensing (coefficient of variation around 0.6). This study successfully overcome this drawback, a simple poling process is demonstrated to both increase the sensitivity and to reduce the variation coefficient of MLCC force sensors. Results indicate that the variation for the MLCCs after re-poling treatment is reduced to 0.02. The effects on the poling voltage and poling time are experimentally investigated. Results show that the MLCC treated with a high poling field can increase sensitivity and also reduce the variation for force sensing. This re-poling treatment is essential for developing a simple and low cost MLCC-based force sensor system that can be used in a wide variety of applications. [ABSTRACT FROM PUBLISHER]

In this study, near-field electrospinning (NFES) was used to fabricate PVDF (Polyvinylidene fluoride) piezoelectric nano-fibers mixed with additional multiwalled-carbon nanotubes (MWCNT). Both mechanical strength and piezoelectric characteristics of a single nano-fiber were discussed. NFES technology can be used to fabricate PVDF piezoelectric fibers with an excellent piezoelectric property. By adjusting velocity of a x-y stage, DC voltage, and the distance between the needle and collector, the morphology and polarization intensity of piezoelectric fiber can be controlled. In addition, the optimal parameters of PVDF solution such as weight percentage of PVDF powder and MWCNT were also discussed. From the observation of XRD (X-ray diffraction), it reveals a high diffraction peak at 2θ=20.8° of piezoelectric crystal β-phase structure with PVDF/MWCNT spherical composite structures in fibers. Actuation property of fixed-fixed single PVDF fiber structure was tested using DC voltage supply, and the fiber has significant deflection in the experiment. The vertical deflection can be observed and compared with model solution. [ABSTRACT FROM PUBLISHER]