Energy harvester device for autonomous intracorporeal capsule

Abstract

An energy harvester device for an autonomous intracorporeal leadless capsule comprises a surface formed on the outside of the body of the capsule that is deformable under the effect of pressure variations in the environment surrounding the capsule. A first capacitor electrode coupling to the deformable surface with the interposition of a damping element forming high-pass filter with respect to pressure variations in the surrounding medium, and a second capacitor electrode mounting on a support connected to the body. The movement of the deformable surface produces a modification of surfaces in vis-à-vis of the two electrodes and/or of the dielectric gap which separates them, with a variation of the capacity of said capacitor. The capacitor is preloaded when its capacity is maximum, and unloaded by transferring energy into storage circuit when this capacity decreases from a reduction in surfaces in vis-à-vis and/or of an increase of the dielectric gap.

What is claimed is: 
     
         1 . An autonomous intracorporeal leadless capsule, comprising:
 a circuit;   an energy harvesting device with at least one movable surface for powering the circuit;   a capsule body having a deformable element directly exposed to an environment exterior of the capsule body, the circuit and the energy harvesting device within the capsule body; and   a mechanical high-pass filter positioned within the capsule body, wherein the mechanical high-pass filter comprises a piston having a rod, the rod extending from the piston out of a chamber and coupling to the at least one movable surface of the energy harvesting device.   
     
     
         2 . The capsule of  claim 1 , wherein the mechanical high-pass filter facilitates movement of the piston during high frequency displacements of the deformable element such that the movement of the piston is transferred to the at least one movable surface. 
     
     
         3 . The capsule of  claim 1 , wherein the mechanical high-pass filter prevents the movement of the piston during low frequency displacements of the deformable element such that the piston does not move. 
     
     
         4 . The capsule of  claim 1 , wherein the chamber is fixed to and movable with the deformable element with respect to at least one of the capsule body and the piston. 
     
     
         5 . The capsule of  claim 1 , wherein the chamber is filled with a fluid, the piston separating the chamber into a first volume and a second volume. 
     
     
         6 . The capsule of  claim 5 , wherein the piston and an inner surface of the chamber are separated by a calibrated clearance. 
     
     
         7 . The capsule of  claim 6 , wherein the calibrated clearance provides a passageway for the fluid to flow between the first volume and the second volume. 
     
     
         8 . The capsule of  claim 6 , wherein the calibrated clearance is sized to restore a pressure equilibrium within the chamber such that low frequency displacements of the deformable element are not transferred to the at least one movable surface. 
     
     
         9 . A method for powering an autonomous intracorporeal leadless capsule, comprising:
 receiving a low frequency pressure variation at an external surface of a deformable member on the capsule, the deformable member displacing in response to the low frequency pressure variation;   using a high pass mechanical filter to prevent displacement of a movable member of an energy harvesting device within the capsule responsive to the displacement of the deformable member due to the low frequency pressure variation;   receiving a high frequency pressure variation at the external surface of the deformable member on the capsule, the deformable member displacing in response to the high frequency pressure variation;   using the high pass mechanical filter to facilitate the displacement of the movable member of the energy harvesting device responsive to the displacement of the deformable member due to the high frequency pressure variation; and   generating energy with the energy harvesting device responsive to the displacement the movable member of the energy harvesting device.   
     
     
         10 . The method of  claim 9 , wherein the high pass mechanical filter comprises a piston coupled to the movable member of the energy harvesting device. 
     
     
         11 . The method of  claim 10 , wherein the displacement of the deformable member due to the high frequency pressure variation causes a displacement of the piston, causing the movable member of the energy harvesting device to displace. 
     
     
         12 . The method of  claim 10 , wherein the piston is enclosed within a fluid-filled chamber that is movable with the deformable member. 
     
     
         13 . The method of  claim 12 , wherein the piston and an inner surface of the fluid-filled chamber are separated by a calibrated clearance. 
     
     
         14 . The method of  claim 13 , wherein the calibrated clearance provides a passageway for a fluid to flow between a first volume and a second volume of the fluid-filled chamber. 
     
     
         15 . The method of  claim 13 , wherein the calibrated clearance is sized to restore a pressure equilibrium within the fluid-filled chamber such that the low frequency pressure variation does not displace the piston. 
     
     
         16 . An autonomous intracorporeal leadless capsule, comprising:
 a circuit;   an energy harvesting device including a capacitor configured to facilitate powering the circuit, the capacitor comprising opposing capacitor electrodes separated by a dielectric gap;   a capsule body having a deformable element directly exposed to an environment exterior of the capsule body, the circuit and the energy harvesting device within the capsule body; and   a mechanical high-pass filter positioned within the capsule body, wherein the mechanical high-pass filter comprises a piston having a rod, the rod extending from the piston out of a fluid-filled chamber and coupling to one of the opposing capacitor electrodes of the capacitor.   
     
     
         17 . The capsule of  claim 16 , wherein the opposing capacitor electrodes are movably suspended relative to the capsule body such that relative movement of the opposing capacitor electrodes generates power for powering the circuit. 
     
     
         18 . The capsule of  claim 16 , wherein the mechanical high-pass filter is configured to mechanically couple the deformable element and the opposing capacitor electrodes during high frequency displacements of the deformable element to generate power for powering the circuit. 
     
     
         19 . The capsule of  claim 16 , wherein the mechanical high-pass filter is configured to mechanically decouple the deformable element and the opposing capacitor electrodes during low frequency displacements of the deformable element. 
     
     
         20 . The capsule of  claim 16 , wherein the piston and an inner surface of the fluid-filled chamber are separated by a calibrated clearance, wherein the calibrated clearance is sized to restore a pressure equilibrium between a first volume and a second volume within the fluid-filled chamber such that low frequency displacements of the deformable element are not transferred to the one of the opposing capacitor electrodes of the capacitor by the piston.