Tuning Non-Linearity in Cascaded Tapered Spring Topologies Of Electromagnetic-Vibrational Energy Harvesters With Enhanced Figure Of Merit

This paper reports a non-linear stretching-strain based electromagnetically transduced vibrational energy harvesters designed on low Young’s modulus FR4 sheet. The reported harvesters use specially designed cascaded tapered spring topologies to tune the non-linear monostable potential energy in the system, while maintaining a consistent beam thickness of 0.25 mm. Also, a graphical representation of energy output in the form of energy eye diagrams has been introduced. These harvester units yield a maximum power of 3.2 mW with a bandwidth of 24.4 Hz when excited at an acceleration of 1 g (where, $\mathrm{g}=9.8 \mathrm{~m} / \mathrm{s}^{2}$) and have a small footprint of $0.73 \mathrm{~cm}^{3}$ with enhanced and optimized figure of merit.