A strain gauge is a device that measures the strain of an object. Strain is described as the change in size or in shape after an object experiences displacement or when there is applied force on the object. Strain is also known as the deformation of the object. The strain gauge was invented in 1938. It is used in different types of applications. The strain on the object can be described as tensile or compressive.
There are different types of strain gauge that are used to measure the displacement of an object. The strain gauge that is used is based on the kind of object that it is measuring the strain for.
Here are some of the applications that use a strain gauge:
- Pressure Sensors. A strain gauge can be used in the manufacturing of pressure sensors or a pressure transducer. A pressure sensor is used in measuring the amount of pressure in substances, such as liquids or gasses. The strain gauge circuit that is used for pressure strain sensors is made out of foil, a thick film, a metal film, silicon and polysilicon. Gauges can be used in combinations of four. This is known as a full bridge. Pressure sensors are also used to observe the different qualities of liquids and gases. Some of the qualities that can be observed are the altitude, the flow and the depth of the object. Pressure sensors are also used in leak testing.
- Piezoresistors. Another application for the strain gauge is for piezoresistors. This is used to measure small amounts of strain of an object. Semiconductor strain gauges are used in this type of measurement. This is ideal for measuring small amounts of strain as semiconductor strain gauges are sensitive to temperature changes. This device is also more expensive than the standard foil gauge.
- Biological Measurements. Strain measurement is also used in the medical field. Strain gauges are used in measuring the swelling of tissue or the blood flow of a person. In this case, a mercury in rubber strain gauge is used. This strain gauge is made up of liquid mercury that is placed inside a rubber tubing. The gauge is then applied on the swelling area of the body and the strain is measured by observing the stretching of the rubber tubing.
- Civil Engineering. In Civil Engineering, strain gauges are used in measuring movements of different structures. The strain gauges for this field are installed on buildings and observed over time in order to know the movement of the structure. A theory is then made on the movement of the structure according to the strain gauge. There are different strain gauges that are used in Civil Engineering. One of them is the Rosette Strain Gauge. The Rosette Strain Gauge is made up of two or more grids that measure the surface of a structure. A strain amplifier is also used in Civil Engineering.
These are some of the applications for using a strain gauge. There are more uses for a strain gauge and there are also different machines and devices that are used in measuring the displacement of an object.