Bistable Wireless Power Transfer
To design a safe and efficient wireless power transfer (WPT) to charge implantable biomedical devices.
Exposure to strong magnetic field could induce electric currents and heat within the human body in what is known as a "stimulation effect." The level of electric currents induced varies depending on the strength and frequency of magnetic fields.
Traditional inductive WPT transmitters operate at a magnetic field of ~1 Mhz, which is incompatible with health standards.
We aim at reducing this frequency to ~1 Hz, to limit the absorption into the body and allow greater efficiency at no risk to health.
To decrease the frequency of magnetic field we proposed to:
- Use a mechanical receiver (instead of inductive) to lower the natural pulsation.
- Exploit structural multistability to enhance low-frequency energetic behaviours.\
To achieve this, we designed a receiver with:
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A buckled-beams based structure inducing bistability.
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A magnetic mass moving with the B field.
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A piezoelectric stack converting mechanical energy to an electrical form.
