In this paper, a new multimodal energy harvesting device consisting of two transduction mechanisms and having unique properties at various operating modes is presented. The hybrid system includes electromagnetic and piezoelectric energy harvesting technologies, and uses linear motion and impact forces from human motion for energy harvesting. The device is based on an unbalanced electromagnetic rotor made of three beams of piezoelectric material that have magnets attached to the ends. The device is to be worn on the legs or arms of a person. Linear motion, from the arms or legs swinging, causes the rotor to spin and the magnets to pass over the coils. Impact forces, from stepping, induce stress on the piezoelectrics which generates voltage across the electrode. The results of several numerical simulations are presented. For the piezoelectric beams, numerical simulations were done to find the deflection, stress, optimum operating frequency, and mode shapes taking into account environmental conditions. For the electromagnetic generation, numerical simulations were done to find the optimal load resistance and power generation for several different orientations. Other design related issues will also be investigated to fully realize the device in real world applications.

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