Dielectric Elastomer Generators for foot plantar pressure based energy scavenging

Parasitic energy scavenging from human-generated vibrations with piezoelectric materials has long been studied in contrast to electromagnetic or conventional electrostatic transducers. Dielectric Elastomers (DEs) are now gaining notice as low-cost electrostatic transducers with high energy densities. However, their transduction mechanism is more intricate. DE Generators (DEGs) are functionally variable capacitors, which require fine-grained control of their charging cycles in order to maximize the energy transduced. Based on a detailed DEG model that incorporates an effective method to time the charge cycles, we contrast the energy scavenged from shoe strikes by DEGs that are virtually embedded into the shoe sole, to similar piezoelectric generators. This comparison for a plantar pressure dataset of a walking subject demonstrates a multiple order-of-magnitude improvement in harvested energy.