Large Strain Sensor Research Articles

Plasma deposition of conductive polymer composites for strain sensor applications

The aim of this work is to develop a large area thin film of a conductive polymer composite (CPC) for large area strain sensor applications. Therefore an alternative plasma deposition process is applied for the manufacturing of CPC as flexible thin films. Plasma polymer films are used as matrix that are deposited with a 60MHz plasma reactor and characterized with dynamic mechanical analyzes (DMA). Copper nanoparticles with different sizes are generated in a special hollow cathode. To enhance the sensitivity of the strain sensor a particle concentration in the matrix at the percolation threshold is important. For this reason, in situ U/I-measurements during particle deposition were done. The characteristics of resistance of the CPC films are analyzed during elongation.

Calibration of a single-mode polymer optical fiber large-strain sensor

We calibrate the phase shift as a function of applied displacement in a polymethylmethacrylate (PMMA) single-mode optical fiber interferometer, operating at a wavelength of 632.8 nm. The phase sensitivity is measured up to 15.8% nominal strain in the fiber. The measured phase–displacement response is compared to a previous analytical formulation for the large deformation response of the polymer optical fiber strain sensor. The formulation includes both the finite deformation of the optical fiber and nonlinear strain-optic effects at large deformations. Using previously measured values for the linear and nonlinear mechanical response of the fiber, the nonlinear strain-optic effects are calibrated from the current experimental data. This calibration demonstrates that the nonlinearities in the strain-optic effect are of the same order of magnitude as those in the mechanical response of the PMMA optical fiber sensor.

114 CNF/柔軟エポキシ複合材料を用いた電気抵抗型大ひずみセンサの開発(GS材料力学2(高機能材料))

114 CNF/柔軟エポキシ複合材料を用いた電気抵抗型大ひずみセンサの開発(GS材料力学2(高機能材料))

A novel fluidic strain sensor for large strain measurement

A novel fluidic strain sensor is proposed with the use of a mixture of glycerin with aqueous sodium chloride encapsulated within an elastomer as a mean for piezoresistive large strain measurement. Electrochemical impedance spectroscopy (EIS) is conducted for strain response measurement and equivalent circuit analysis is applied for explaining the strain-affected ion transportation behavior of the sensor. The applied strain has caused an increase in both the resistance to charge transfer ( R ct) and the resistance of the salt solution which is reflected in an increase in the resistance of the system ( R sys). A parabolic relationship between the real part of the impedance ( Z re) and the true strain ( ɛ) for an applied strain of up to about 30% is verified. In addition, a novel fluid encapsulation technique by applying oxygen plasma surface modification is introduced. Aqueous sodium chloride is successfully encapsulated within an elastomeric casing with a pattern and this sensor is capable of measuring large strain of even up to about 40%. This method is suggested as an industrial fabrication technique for the strain sensor. The use of ionic liquids for green chemistry has been suggested for years and its use as an electrical conductive media in large strain sensor technology is found to be direct and environmentally friendly.

Intrinsic polymer optical fibers for large deformation strain sensors

Intrinsic polymer optical fibers for large deformation strain sensors

P1 CNF複合材料の電気抵抗型大ひずみセンサへの適用(OS1)

P1 CNF複合材料の電気抵抗型大ひずみセンサへの適用(OS1)