Design and fabrication of a shielded interdigital sensor for noninvasiveIn situreal-time production monitoring of polymers

Abstract

Interdigital sensors (IDS) have received great attention for production monitoring of polymers over the past decade. However, conventional IDS are limited by high noise to environment due to the dual side access of the sensor, low nominal capacitance, and sensitivity. In this study, a shielded IDS fabricated by flexible circuit board (FCB) technology is presented to overcome these challenges. Compared to conventional sensors, the environmental dependence of the new sensor is minimized by the copper shield. Furthermore, nominal capacitance of at least 350% higher, and an increase of sensitivity per unit area are achieved. To demonstrate the capabilities of the new IDS, a FCB comprising the proposed sensor is fabricated, attached to a mould, and successfully applied for in situ real‐time production monitoring of an epoxy resin. The resulting flexible sensor is noninvasive towards the fabricated parts, and measures the key stages along the production process. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 2028–2037

Adhesion of Multifunctional Substrates for Integrated Cure Monitoring Film Sensors to Carbon Fiber Reinforced Polymers

“…The sensitivity of these sensors strongly depends on the geometry of the interdigital electrodes [7]. Sensitivity and immunity to interference can be further enhanced by electrically shielding the sensor with a copper coating on the bottom of the PI film used [9].…”

Multi-material fused deposition modelling for integration of interdigital dielectric sensors into carbon fibre composite tooling for in process cure monitoring

“…Non-destructive monitoring methods enable the assessment of the CFRP cure progress without impacting the functionality of the finished part. Many have been explored to date, including the use of optical fibres [5], ultrasonic [6], inductive coupling [7] and dielectric [4,[8][9][10][11][12][13] methods. The limiting factor for these This study introduces the concept of printing two thermoplastic materials in a single 3D Printing processone conductive the other non-conductiveto form interdigital sensor structures for Dielectric Analysis in mould tools for cure monitoring of the epoxy matrix during the Carbon Fibre Reinforced Polymer manufacturing process.…”

A Flow-Through Microfluidic Relative Permittivity Sensor

“…Microfluidic relative permittivity sensors have great potential for fluid discrimination and composition determination [1,2]. Applications include the detection of medicine composition in medical infusion pumps [3], single-cell impedance cytometry [4,5], composition detection in flow chemistry [6,7], production monitoring of polymers [8], void-fraction measurement in two-phase flow [9,10], and measurement of glucose concentration in water [11,12] or water content in oil [13,14].…”