Harnessing vibrations: A review on structural architecture and design ideology of the cantilever beam based piezoelectric energy harvesters

Piezoelectric energy harvesting (PEH) offers a compelling alternative to traditional power sources, particularly for low-power devices in wireless sensor networks (WSNs), MEMS, and IoT systems. Among various harvesting architectures, cantilever beam-based configurations have emerged as the most prevalent due to their simple construction, ease of fabrication, and high energy density. However, their performance is often constrained by narrow frequency bandwidths and reduced efficiency under off-resonance conditions. This review paper provides a comprehensive analysis of the structural advancements and design methodologies developed to address these limitations. It explores diverse cantilever geometries, including rectangular, trapezoidal, tapered, zigzag, and biomimetic forms, focusing on their impact on strain distribution, resonant behavior, and power output. Further emphasis is given to boundary augmentation strategies at both fixed and free ends, incorporating dynamic magnifiers, magnetic tuning, and multi-stability to broaden operational frequency ranges. The study also reviews the role of proof mass configurations, piezoelectric patch placement, and hybrid systems combining piezoelectric with electromagnetic or electrostatic mechanisms to improve harvesting efficiency. Power output and frequency response data from key studies are tabulated for direct comparison. By systematically categorizing existing designs and correlating structural features with performance outcomes, this review aims to guide researchers in selecting or innovating cantilever-based PEH solutions suited to specific application environments. Ultimately, the paper highlights the evolution of cantilever-based energy harvesting systems and identifies emerging design trends that promise to meet the growing demand for self-sustaining, scalable, and efficient energy sources.