Design of a motion energy harvester based on compliant mechanisms

Abstract

This work presents a novel design, model and prototype of a motion energy harvester based on bi-stability and frequency up-conversion. The Parametric Frequency up-converter Generator (PFupCG). The PFupCG was designed to harvest energy under conditions where the amplitude of the driving motion is larger than the internal displacement limit. Instead of an impact member, the PFupCG uses a compliant suspension mechanism that combines a bi-stable characteristic with a strong stiffening behavior as a result of geometric effects. This resulted in a prototype of the PFupCG with an internal-to-applied motion amplitude ratio of 0.2. A case study was carried out where the PFupCG was analyzed by simulation and experiment for vibration conditions representative of human walking motion (2Hz, 25 mm).