The basic principle of strain gauge pressure sensor
Strain gauge pressure sensor straingauge, pressure, transducerThe working principle of the resistance strain gaugeThe working principle of the metal resistance strain gauge is that the resistance of the strain is changed on the base material. The resistance changes with the mechanical deformation, which is commonly called the resistance strain effect. The resistance of a metal conductor can be expressed in the lower order:Type: resistivity - metal conductor (. Cm2/m)S - cross sectional area of conductor (cm2)L - conductor length (m)We use metal wire strain resistance as an example, when the metal wire under the action of external force, its length and cross-sectional area will change from the type of it is easy to see that the resistance value is changed, if the wire under the action of external force and elongation, the increase in the length and cross-sectional area of reduced resistance value will increase. When the wire is compressed by external force, the length decreases, the cross section increases, and the resistance decreases. As long as the change in the resistance (usually measuring the voltage at both ends of the resistor), the strain of the strain wire will be obtained
Principle and application of strain gauge pressure sensorMechanics sensor's great variety, such as resistance strain gauge pressure sensor, semiconductor strain gauge pressure sensor, piezoresistive pressure sensor, inductive pressure sensor, capacitive pressure sensor, resonant pressure sensor and capacitive acceleration sensor. But piezoresistive pressure sensor is the most widely used. It has very low price, high accuracy and better linear characteristics. Here we mainly introduce this kind of sensor.In the extraction of piezoresistive force sensors, we first recognize the resistance strain gauges. A resistance strain gauge is a sensitive device that converts strain changes on a measured piece into an electrical signal. It is one of the major components of piezoresistive strain sensors. The most widely used resistance strain gages are two kinds of metal resistance strain gauges and semiconductor strain gauges. There are two kinds of metal resistance strain gauges, namely, filament strain gauge and metal foil strain gauge. Usually the gage through special adhesive bonding in close mechanical strain matrix, when the substrate stress occurs when the stress changes, resistance strain gauge together the deformation, the strain sheet resistance change, so that the voltage on resistance change. The strain resistance of the strain gauge is usually smaller when the force is applied. Generally, the strain gauges are made up of strain bridges and amplified by subsequent instrumentation amplifiers, which are then transmitted to them
