Abstract: An embodiment of the invention is an in-vivo blood pressure sensor device including a strain transducer and flexible biocompatible material that carries the strain transducer. The flexible biocompatible material is configured to encircle the outside of a blood vessel when surgically installed. A preferred embodiment in-vivo blood pressure sensor device of the invention includes a strain transducer carried by a flexible biocompatible ring that is configured to be surgically installed to encircle a blood vessel. The device also includes passive circuitry encased in biocompatible material for sensing strain in the strain transducer and for providing data to an external reader. The passive circuitry is also configured to be surgically installed in a subject.

Abstract: A three-dimensional micro-electro-mechanical-systems (MEMS) capacitive bending and axial strain sensor capacitor is described. Two independent comb structures, incorporating suspended polysilicon interdigitated fingers, are fabricated simultaneously on a substrate that can displace independently of each other while attached to a substrate undergoing bending or axial deformation. A change in spacing between the interdigitated fingers will output a change in capacitance of the sensor and is the primary mode of operation of the device. On the bottom and to the end of each comb structure, a glass pad is attached to the comb structure to allow for ample surface area for affixing the sensor to a substrate. During fabrication, tethers are used to connect each comb structure to maintain equal spacing between the fingers before attachment to the substrate. After attachment, the tethers are broken to allow independent movement of each comb structure.

Abstract: A three-dimensional micro-electro-mechanical-systems (MEMS) capacitive bending and axial strain sensor capacitor is described. Two independent comb structures, incorporating suspended polysilicon interdigitated fingers, are fabricated simultaneously on a substrate that can displace independently of each other while attached to a substrate undergoing bending or axial deformation. A change in spacing between the interdigitated fingers will output a change in capacitance of the sensor and is the primary mode of operation of the device. On the bottom and to the end of each comb structure, a glass pad is attached to the comb structure to allow for ample surface area for affixing the sensor to a substrate. During fabrication, tethers are used to connect each comb structure to maintain equal spacing between the fingers before attachment to the substrate. After attachment, the tethers are broken to allow independent movement of each comb structure.

Abstract: A three-dimensional micro-electro-mechanical-systems (MEMS) capacitive bending and axial strain sensor capacitor is described. Two independent comb structures, incorporating suspended polysilicon interdigitated fingers, are fabricated simultaneously on a substrate that can displace independently of each other while attached to a substrate undergoing bending or axial deformation. A change in spacing between the interdigitated fingers will output a change in capacitance of the sensor and is the primary mode of operation of the device. On the bottom and to the end of each comb structure, a glass pad is attached to the comb structure to allow for ample surface area for affixing the sensor to a substrate. During fabrication, tethers are used to connect each comb structure to maintain equal spacing between the fingers before attachment to the substrate. After attachment, the tethers are broken to allow independent movement of each comb structure.

Abstract: An embodiment of the invention is an in-vivo blood pressure sensor device including a strain transducer and flexible biocompatible material that carries the strain transducer. The flexible biocompatible material is configured to encircle the outside of a blood vessel when surgically installed. A preferred embodiment in-vivo blood pressure sensor device of the invention includes a strain transducer carried by a flexible biocompatible ring that is configured to be surgically installed to encircle a blood vessel. The device also includes passive circuitry encased in biocompatible material for sensing strain in the strain transducer and for providing data to an external reader. The passive circuitry is also configured to be surgically installed in a subject.