A wave-inspired ultrastretchable strain sensor with predictable cracks

The phenomenon in nature can always inspire human beings in technology. Waves in nature are the transmission of force and energy and the microstructure of wave can concentrate stress at the troughs. The concept of wave is applied to our crack-based strain sensor to benefit the improvement of stretchability of the crack sensor with a formation of predictable cracks. The wave-inspired crack-based strain sensor has wide strain range under the condition of ensuring the extremely high sensitivity. The specific tensile properties of the wave-like crack-based strain sensor are gauge factor (GF)similar to 80 (0% < epsilon < 30%), GF similar to 380 (30% < epsilon < 60%), GF similar to 2585(epsilon > 60%). In addition, it is easy to fabricate such sensors on a large scale with simple manufacturing processes. To demonstrate its excellent sensitivity, the sensor is employed in the monitoring of human expressions and motions. Meanwhile, robot behavior control and weight measurement are used to embody the wide strain range of the sensor. The crack-based strain sensor inspired by wave shows tremendous superiority in flexible wearable devices. (C) 2019 Elsevier B.V. All rights reserved.