Flexible CNT-array double helices Strain Sensor with high stretchability for Motion Capture

Abstract

Motion capture is attracting more and more attention due to its potential wide applications in various fields. However, traditional methods for motion capture still have weakness such as high cost and space consuming. Based on these considerations, a flexible, highly stretchable strain sensor with high gauge factor for motion capture is fabricated with carbon nanotube (CNT) array double helices as the main building block. Ascribed to the unique flexible double helical CNT-array matrix, the strain sensor is able to measure strain up to 410%, with low hysteresis. Moreover, a demonstration of using this strain sensor for capture hand motion and to control a mechanical hand in real time is also achieved. A model based on finite difference method is also made to help understand the mechanism of the strain sensors. Our work demonstrates that strain sensors can measure very large strain while maintaining high sensitivity, and the motion capture based on this strain sensor is expected to be less expensive, more convenient and accessible.

The Design and Characterization of a Flexible Tactile Sensing Array for Robot Skin

“…Intelligent robot skin with tactile sensing capability can help robots operate in unknown environments and safely interact with people and objects [2]. In the literature, flexible tactile sensors can be classified into several sensing mechanisms, which are capacitive [3,4,5,6], piezoresistive [7,8,9,10], piezoelectric [11,12,13], thermoelectric [14], triboelectric [15,16], and other functional materials with sensing characteristics [17,18,19,20]. Among these, a capacitive sensing mechanism is usually preferred because of its simple structure, stable performance, and temperature independence [5].…”

Magnetic assembly of transparent and conducting graphene-based functional composites

“…Such a small resolution has not yet been reported in stretchable and transparent strain sensors used for health-monitoring devices where high strains, typically up to 300%, is the main property targeted 50 51 52 . In these systems, an error in strain of 2% is usually limiting the sensitivity 53 . Although other stretchable composites have been developed that reaches a detection limit down to 0.1% strain in carbon black filled rubber 54 or 0.5% in graphene and silver nanoparticles sandwich structures 55 , they do not possess the optical transparency required for optoelectronic devices.…”

Literature Review

“…These pressure sensors displayed a change in conductivity up to 2200 cm -1 for maximum pressure and strain of 50 kPa and 150% from its reference position. The pressure sensors developed from flexible-CNT-array double helices (CNTADH) were also used for motion capturing application (Li et al 2015a). Two CNTs strands were grown with Lamellar-layered double hydroxides (LDHs) were used as catalysts to grow two CNTs strands via sonication with a surfactant in water.…”

“…The sensors depicted small hysteresis with a maximum measured pressure of 410% from its reference position. Choi et al 2016;Dai et al 2015;Ding et al 2016;Kanoun et al 2014;Li et al 2015a;Lim et al 2016;Loh et al 2007;Michelis et al 2014;Nakamoto et al 2015;Park et al 2008;Park et al 2016b;Roh et al 2015;Sanli et al 2017;Souri et al 2015;Tadakaluru et al 2014;Wang et al 2016;Yan et al 2014;Zhang et al 2015a;Zhao et al 2016a;Zhao et al 2014;Zhou et al 2017a) are some of significant research work done in the past few years on pressure and strain sensors.…”