A novel fabrication process to realise piezoelectric cantilever structures for smart fabric sensor applications

Abstract

Abstract-This paper reports a novel process for realising freestanding piezoelectric cantilevers printed on fabric for potential use as a wearable sensor. Piezoelectric cantilever structures were fabricated by screen printing a piezoelectric stack on top of a structural layer that is supported by a sacrificial material during printing. The sacrificial layer was subsequently removed in an oven at 160 °C for 30 minutes which is sufficient to fully release the cantilever beam from the substrate. The samples were polarised by applying an electric field across the piezoelectric stack. Testing on an electromechanical shaker shows that the cantilevers have resonant frequencies at 390 and 260 Hz for beam lengths of 12 and 15 mm, respectively. The beams produced maximum outputs of 38 and 27 mV at an acceleration of 11.76 m/s 2 , respectively.

A WiFi tracking device printed directly on textile for wearable electronics applications

“…Originally developed by the researchers from University of Southampton [1][2][3][4][5][6][7][8][9], UK, interface layer method employs an intermediate screen-printed layer that covers the surface profile of a material rendering it flat and relatively smooth [1]. The specially designed polyurethane-based dielectric ink was used to form an interface layer.…”

“…Such fabric is cheap and easy to acquire, making this method very accessible and promising for wearable electronics. Up until now the conductive printing via interface layer method was limited to simple structures such as lines, patches, electrodes, and simple antennas [1][2][3][4][5][6][7][8][9][10][11][12][13]. No complete circuit design involving an integration of electronic components on textile has been demonstrated in this medium before.…”

“…The interface layer method, initially proposed by researchers at the University of Southampton [1][2][3][4][5][6][7][8][9][10][11][12][13], can be used with a variety of textiles such as polyester/cotton. Such fabric is cheap and easy to acquire, making this method very accessible and promising for wearable electronics.…”

“…onto textile [19][20][21] • knitting, weaving or embroidering fully conductive threads or conductive coatings into the fabric [22][23][24][25] • conductive printing on textiles [1][2][3][4][5][6][7][8][9][10][11][12][13][26][27][28][29][30][31][32][33][34][35][36][37] All three categories are perfectly viable production methods and have their uses, advantages and shortcomings. However, only conductive printing on textile can potentially acquire efficient, fast and reliable mass production traits inherent to the electronic industry.…”

“…Furthermore, the primary ingredient in interface layer method is the interface layer ink. Current ink Fabink UV IF-4 which is used in every interface layer method research paper [1][2][3][4][5][6][7][8][9][10][11][12][13] is much more expensive than regular dielectric inks. The high cost of the current interface layer ink is prohibitive, and research attempts should be made to optimize a regular dielectric ink to function with textiles.…”