Mechanical gauge for estimating inductance changes in resonant power transfer systems with flexible coils for use with implanted medical devices

A method of powering an implantable ventricular assist device with an external charging device comprising a resonant circuit, the method comprising:

• receiving one or more signals generated by one or more sensors attached to a deformable coil of the resonant circuit, wherein the one or more signals are indicative of a deformation of the deformable coil;
• processing the one or more signals to generate a deformation value indicative of the deformation of the deformable coil;
• determining a performance property of the deformable coil based on the deformation value by querying a memory with the deformation value to retrieve one or more values indicative of the performance property;
• identifying an adjustment to a tuning of the resonant circuit based on the performance property of the deformable coil;
• tuning the resonant circuit according to the adjustment to the tuning of the resonant circuit;
• and
• driving the resonant circuit to transmit power to a secondary coil electrically coupled with the implantable ventricular assist device to power the implantable ventricular assist device.