Substrate integrated waveguide textile antennas as energy harvesting platforms

Textile multi-antenna systems are key components of smart fabric and interactive textile (SFIT) systems, as they establish reliable and energy-efficient wireless body-centric communication links. In this work, we investigate how their functionality can further be extended by exploiting their surface as an energy harvesting and power management platform. We provide guidelines for selecting an appropriate antenna topology and describe a suitable integration procedure. We demonstrate this approach by integrating two flexible solar cells, a micro-energy cell and a flexible power management system onto a well-chosen wearable substrate integrated waveguide cavity-backed textile slot antenna, without affecting its performance, to enable energy harvesting from solar and artificial light. In addition, the compact and highly-integrated harvesting module provides a terminal for connecting a thermoelectric generator, enabling thermal body energy harvesting. Measurements in a realistic indoor environment have demonstrated that this hybrid energy harvesting approach leverages a more continuous flow of scavenged energy, enabling energy scavenging in most of the indoor and outdoor scenarios

A two-step hybrid approach for modeling the nonlinear dynamic response of piezoelectric energy harvesters

An effective hybrid computational framework is described here in order to assess the nonlinear dynamic response of piezoelectric energy harvesting devices. The proposed strategy basically consists of two steps. First, fully coupled multiphysics finite element (FE) analyses are performed to evaluate the nonlinear static response of the device. An enhanced reduced-order model is then derived, where the global dynamic response is formulated in the state-space using lumped coefficients enriched with the information derived from the FE simulations. The electromechanical response of piezoelectric beams under forced vibrations is studied by means of the proposed approach, which is also validated by comparing numerical predictions with some experimental results. Such numerical and experimental investigations have been carried out with the main aim of studying the influence of material and geometrical parameters on the global nonlinear response. The advantage of the presented approach is that the overall computational and experimental efforts are significantly reduced while preserving a satisfactory accuracy in the assessment of the global behavior