Robust polymer-HfO2 thin film laminar composites for tactile sensing applications. (20th December 2018)

• Record Type: Journal Article
• Authors: Sivaneri, Kavin V I; Ozmen, Ozcan; Aziziha, Mina; Sabolsky, Edward M; Evans, Thomas H; DeVallance, David B; Johnson, Matthew B
• Is Part Of: Smart materials and structures. Volume 28:Number 2(2019:Feb.)
• Publication Date: 2018-12-20
• Subjects: tactile sensor -- capacitance -- polymer-ceramic composite -- HfO2 thin film -- space application -- flexible electronics -- flexible tactile sensor; Smart materials -- Periodicals; Strucural design -- Periodicals; 620.11
• DOI: 10.1088/1361-665X/aae00f
• Languages: English
• ISSNs: 0964-1726

Abstract

Abstract: A method for high resolution tactile sensing for robotic end-effectors used in variable environmental conditions is required for practical robotic applications, such as heavy industry, construction, military and space applications. In this work, a robust, flexible tactile sensor based on a capacitive sensing mechanism with high sensitivity and stability that can operate between −60 °C and 120 °C was developed. The active sensing thick film was composed of a 2:2 connective polymer-ceramic laminar composite. A stress-sensitive elastomer (Arathane 5753 A/B) was used as the primary compliant layer within the laminar architecture, and a HfO2 thin film was used as the dominating dielectric layer to improve the sensitivity of the sensor. The sensors were fabricated on a flexible polyimide film (Kapton) to conform to the end-effector geometry. The fabricated sensor showed good sensitivity and cycle stability (between 0 and 360 kPa). The capacitance change due to temperature variations were studied in detail. Three different capacitive sensor architectures were developed to study the influence of the HfO2 layer on the sensitivity of the sensor. Thermomechanical loading cycles were performed with in situ electrical acquisition to characterize the sensor. Chemical and structural characterization of the HfO2 layer deposited on a flexible substrate was implemented using conductive atomic force microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy, and the optical properties were analyzed by the ultra-violet visible spectrophotometer.