This paper performs a design parameter study for development of a self-powering brain neurostimulation system by harvesting deformation energy generated from mandibular (lower jaw) movements. For decades, scientists recognized that electrical stimulation of the brain (deep brain stimulation, DBS) has the potential to treat a variety of refractory medical conditions including chronic pain, Parkinson’s disease, movement disorders, major depression and epilepsy. A commercial DBS device comprise a stimulation lead, neurostimulation unit with microcontroller, and a battery for power supply. The batteries in DBS need replacement every 3~5 years and thus problematic because additional surgery is required to replace them. This paper describes an innovative technology to power DBS by converting stresses/strains in the mandible caused by jaw movements into electrical energy using piezoelectricity. The proposed energy harvester has a multilayer layout composed of piezoelectric composite and biocompatible titanium layers, and will be secured in place on the body of the mandible using titanium screws. For optimal design of this harvester, we build an experimentally verified FEM model for the mandible and harvester assembly, and perform parameter study of the energy harvester. The parameter study on the size/location of the piezoelectric material as well as its cross sectional properties of piezoelectric harvester is performed and experimentally tested. Its practical use by integrating it with electrical circuit is also discussed.
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