Paper property sensing system

摘要

A sensor system for measuring physical properties of paper. The paper property sensor system includes a surface and a diaphragm opposed to each other. The small diaphragm includes a first pair and a second pair p-type piezoresistors. Each piezoresistor of the first pair has a longitudinal axis and is located perpendicular to and very close to one of the long edges of the diaphragm. Each piezoresistor of the second pair has a longitudinal axis and is located between and parallel to first pair of piezoresistors, and away from the short edges of the diaphragm. Coupling the first pair of piezoresistors with the second pair via a Wheatstone bridge produces a voltage representative of the shear force exerted by a sheet.