Vibration Energy Harvesting by means of Multi-physical Devices

The reduction in the power demand of sensors and other electronic devices fosters the development of vibration energy harvesters based on piezoelectric materials suited to many applications in industry, home automation, biomedical devices, and vehicles. The research topic concerns the analysis and the development of innovative piezoelectric energy harvesters, which convert the mechanical energy available in the environment into electrical energy. The research develops in parallel with the European project InComEss - INnovative polymer-based COmposite systeMs for high-efficient Energy Scavenging and Storage. The main objective of the InComEss project is to implement innovative material systems and structures for energy harvesting and electrical energy storage, based on the combination of new functional and advanced composite materials. Two use cases are considered for the implementation and testing of these innovative energy harvesters. The research activity concerned the “Aeronautical” use case and the “Building” use case. The first concerns the development of a hybrid energy harvester, based on thermo-piezoelectric energy generator, which exploits the vibration of the slats of the aircraft’s wings. The second deals with the development of a piezoelectric energy harvester which exploits the dynamic pressure of the wind on the building’s façade. Both the scenarios can be referred to as Structural Health Monitoring (SHM) applications, since the available mechanical energy is converted to supply a network of sensors for monitoring the structure. The research aimed to develop analytical and numerical models to estimate the performance of the novel energy generators. For the Aeronautic use case, a sophisticated semi-analytical-numerical model, which integrate the large-scale model of the slat with the small-scale model of the energy generator, is presented. For the building use case, an experimental analysis of different designs of piezoelectric energy harvesters is discussed, in order to identify the best configuration to extract and convert the mechanical energy available in turbulent wind flow. Moreover, the research activities focused also on the identification of the piezoelectric constant of novel piezoelectric material, as the one developed within the framework of the InComEss project.