Crack-enhanced mechanosensitivity of cost-effective piezoresistive flexible strain sensors suitable for motion detection. (21st September 2018)

• Record Type: Journal Article
• Authors: Xiao, Yao; Jiang, Shuwen; Zhao, Xiaohui; Jiang, Hongchuan; Zhang, Wanli
• Is Part Of: Smart materials and structures. Volume 27:Number 10(2018:Oct.)
• Publication Date: 2018-09-21
• Subjects: flexible strain sensor -- piezoresistive polymer composite -- crack-enhanced strain sensor -- motion detection; Smart materials -- Periodicals; Strucural design -- Periodicals; 620.11
• DOI: 10.1088/1361-665X/aadc89
• Languages: English
• ISSNs: 0964-1726

Abstract

Abstract: In this work, a crack-enhanced flexible strain sensor was developed based on polyimide/carbon black piezoresistive polymer composite. A simple, cost-efficient approach to introduce micro-cracks into the sensitive film was proposed. By periodically tearing the sensitive film from a supporting layer, the aligned micro-cracks were generated in the sensitive film, and the crack size and density were modulated by repeated tearing-off times and finally saturated. This crack-enhanced strain sensor exhibited high mechano-sensitivity with a gauge factor of ∼470 at 0.2% strain. We demonstrated that the crack-enhanced strain sensor was capable of monitoring the body joint motion. In particular, the patterns of finger grabbing and elbow bending could be detected and distinguished using this sensor. The high sensitivity of this crack-based strain sensor, together with its low hysteresis, good repeatability and simplicity, low cost in fabrication, make it suitable for motion detection and recognition.