A Multidirectional Forearm Electromagnetic Generator Designed via Numerical Simulations

Harvesting biomechanical energy from daily human body motions provides a promising and sustainable power solution for wearable electronics, whose current supplies, i.e., batteries, have unsatisfactory capacity durability due to volume, shape, flexibility constraints. Electromagnetic generators (EMGs) are favorable transducers because of their high energy-conversion efficiency, low dependence on frequencies, long-term stability. However, an EMG that can effectively harvest multi-directional arm at aperiodic frequencies yet be created. Here, we introduce unique configuration by combining linear helix frame into monolithic unit (EMG-LH), enabling the scavenge all kinds up 6 degrees freedom (DOFs) (movement along XYZ axes forearm rotations). The geometry is designed optimized according numerical simulations. To clarify working mechanism maximize output, copper coils’ winding pattern, magnets’ velocity profiles, resulting voltage output numerically simulated then experimentally verified. Our EMG-LH outperforms EMGs (EMG-Ls) (EMG-Hs) in harvesting motions. This work explicitly presents forearm-wearable harvester as source electronics.