Optimization of energy harvesting concepts from vibration by piezoelectric actuator design

The power supply is a major need in the sensor network deployment for structural monitoring applications in non-accessible structures and components. To develop smart structures within the Industry 4.0 and the smart anything everywhere concepts, autonomous integrated sensors are needed. Under this premise, the present work presents several low cost energy harvesting solutions to support the design phase as a function of the surrounding available vibrations and the electronic components requirements. The simplest system to evaluate the potential design strategies is the evaluation of the piezoelectric sensor in a cantilever configuration that induces the mechanical stress in the piezoelectric layer to produce the voltage to be stored in the battery. The most efficient design is the bimorph concept, where two thin piezoelectric layers separated by a non-active intermediate layer are used. The flexibility, robustness and efficiency of homemade and commercially available bimorph PZT and PVDF sensors designs has been tested by authors under similar acceleration forces.