Research On Capacitive Tactile Sensor Based On Porous Dielectric Material

With the development of wearable technology,flexible sensors that meet the characteristics of light weight,high sensitivity,and wide measurement range have wide application prospects in many fields such as electronic devices and robots.In this paper,the foamed GNPs/CB/SR nanocomposites and the capacitive sensing unit based on porous nanocomposites dielectric materials were analyzed and researched experimentally.The capacitive sensing unit based on porous nanocomposites dielectric materials was made to provide important practical significance for improving the performance of capacitive sensors,and applied to artificial intelligence e-skin.The nanocomposites were formed by using physical foaming technology and the influence of foaming on percolation threshold,conductivity and relative density of composite materials had been studied.The relationship between the microcellular structure and the electrical conductivity of the foamed nanocomposites was established by combining effective conductive path theory.The experimental results showed that the porous material had a seepage threshold in advance due to foaming.It was worth noting that the product of AC-agent concentration and foaming time reaches a certain value,when the highest electrical conductivity of foamed nanocomposites was achieved.The conductivity of foamed nanocomposites would change with the non-monotonicity of the foaming level,which was essential for further optimizations of the foaming materials with the targeted electrical conductivity.The highly conductive and elastic porous foamed composites were used to prepare dielectric layer of capacitive tactile sensing element.The sensing principle,structure design and sensitivity optimization of the sensing unit had been studied.A signal processing system to suit the characteristics of the capacitive tactile sensor array had been designed,and the touch-pressure sensing information was displayed graphically in real time through the LabVIEW platform.The experimental results showed the capacitive tactile sensor array using porous composite dielectric material displayed good stability and higher sensitivity in terms of tactile sensing and it had great potential application,such as the electronic skin and other fields in the future.