Energy & Cost efficient touch based Appliances
The goal of the project EcoTouch is the demonstration of a new technology (PyzoFlex®) being able of harvesting piezoelectric energy, thus leading to energy efficient products of different appliances. The main advantages of this technology are (i) energy and cost efficient production due to printing technologies (ii) large area piezoelements on flexible (stretchable) surfaces (iii) integration of piezogenerators on arbitrary (3D) surfaces (iv) environmental friendly production processes including a good energy balance (v) the demonstration of this technology in zero energy, spatially resolved input devices in the field of mobile control units. Furthermore, the energy balance of many different applications can be optimized by integrating the EcoTouch technology in various appliances.
The generation of electrical energy by using environmental sources like temperature, vibrations, pressure or wind is called energy harvesting. Since the utilization of environmentally forces for powering all kinds of machines has always been of great (economic) interest, first examples can be considered being water- and windmills many centuries ago. Nowadays, the need of decentralized power-supply for many mobile devices (radio controller, wireless sensor networks, mobile consumer electronics…) is one of the main driving forces for finding new technologies enabling locally restricted, renewable and decentralized energy supply. Flexible and lightweight piezoelectric generators that produce energy from pressure, vibration or touch right next to a sensor or in a remote control or even in clothes open up new applications without the limitations of batteries and cables. Furthermore the product life cycle of low energy devices can be extended having a positive environmental effect.
Within the project large area we developed printed piezoelectric elements for the generation of electrical energy. These piezogenerators convert vibration or other changes in pressure into electrical energy. The active materials used for printing are ferroelectric (co)polymers from the PVDF-class. After electric polarization these materials show strong piezoelectric activity combined with chemical robustness, UV- and weather resistance as well as being hardly inflammable.
The poled ferroelectric polymer film was embedded in between two printed electrodes on a flexible foil and were integrated with likewise printed touch panels to increase efficiency by reducing the charging cycles of the battery.
Take a look at our work
C. Rendl, P. Greindl, K. Probst, M. Behrens, and M. Haller, 2014. In CHI14: Proceedings of the 32nd International Conference on Human Factors in Computing Systems, Toronto, ON, Canada, 2014.
C. Rendl, P. Greindl, M. Haller, M. Zirkl, B. Stadlober, and P. Hartmann, 2012. In UIST 12: Proceedings of the 25th annual ACM symposium on User interface software and technology, New York, NY, USA, 2012, pp. 509-518.