Flexible pressure sensor array and method for fabricating the same

Inventors

Fu, Li • Xu, Tao • CHONG, Yam

Assignees

Nano and Advanced Materials Institute Ltd

Abstract

The present disclosure provides a flexible pressure sensor array and method for fabricating the same. The pressure sensor array comprises a pressure-sensing substrate, top electrodes and bottom electrodes. The pressure-sensing substrate comprises a piezoresistive material, a fabric and pressure-sensing columns. The top electrodes and the bottom electrodes are attached to the pressure-sensing columns. The pressure sensor array is ultra-flexible and conforms to 3-dimensional surface for pressure monitoring.

Core Innovation

The invention relates to a pressure sensor array that uses a pressure-sensing substrate including piezoresistive material. The pressure-sensing substrate includes a fabric divided into a plurality of filling portions and a non-filling portion, where the plurality of filling portions are separated with each other by the non-filling portion of the fabric and the non-filling portion is not filled with the piezoresistive material. The fabric filling portions form electrically separated pressure-sensing columns, where each column comprises a respective filling portion filled with the piezoresistive material and includes a top column surface and a bottom column surface.

The array further includes a plurality of top electrodes aligned in rows from a planar surface view of the pressure-sensing substrate. Each top electrode electrically connects to one or more respective top column surfaces of the pressure-sensing columns and is stitched to the pressure-sensing substrate to be periodically attached to the top column surface and a bottom surface of the non-filling portion. In addition, a plurality of bottom electrodes are aligned in columns from the planar surface view, each bottom electrode electrically connecting to one or more respective bottom column surfaces and stitched to be periodically attached to the bottom column surface and a top surface of the non-filling portion.

The top electrodes and bottom electrodes are stitched in a way that each cross point between the top electrodes and the bottom electrodes does not incur short circuit but only defines pixel point from the planar surface view of the pressure-sensing substrate. The disclosed configuration enables a pressure-mapping system that images a pressure distribution profile using electrical resistance measurement and a computer to generate pressure profiles from resistance values. The disclosed embodiments also enable reliable operation while conforming to 3D surfaces through protective plastic covers.

Claims Coverage

The independent claims include a pressure sensor array with 2 electrode layers stitched to electrically isolated piezoresistive columns defined by fabric filling and non-filling portions, using a cross-point electrode arrangement that avoids short circuits and defines pixel points. The main inventive features focus on the separated fabric filling/non-filling architecture that yields electrically isolated columns and the electrode stitching layout that defines pixel points without short circuit.

Overall, the claim coverage is centered on a fabric-based pressure-sensing substrate that uses a non-filling separation portion to electrically isolate piezoresistive pressure-sensing columns, combined with a stitched top-and-bottom electrode matrix whose cross points do not incur short circuits and instead define pixel points from a planar surface view.

Stated Advantages

Documented Applications