Low-amplitude vibrations represent a vast untapped energy source, but conventional harvesters fail to generate usable power below critical thresholds. This paper presents a novel magneto-spring mechanism that fundamentally transforms pendulum-based energy harvesting through non-contact torque modification. By strategically placing permanent magnets around a power spring, we achieve tunable mechanical energy storage without physical alteration. Finite element analysis using Arkkio’s method shows superior accuracy in predicting magnetic torque contributions. Experimental validation demonstrates remarkable improvements: N48 magnets achieve 19.4 mW peak power (273% increase) and 7.7 mW average power compared to conventional springs. The system reduces required angular displacement by up to 3 turns while maintaining higher voltage outputs. This breakthrough enables efficient energy harvesting from previously unusable low-frequency, irregular vibrations in IoT and industrial monitoring applications.
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