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Types of Strain Gauge

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2.2 Types of Strain Gauge Types of strain gauges are classified into foil strain gauges, metal strain gauges and semiconductor strain gauges, etc. 2.2.1 Foil Strain Gauge The foil strain gauge has metal foil on the electric insulator of the thin resin and gauge leads attached, as shown in Fig. 2.1 below. Fig: 2.1 Foil strain gauge The strain gauge is bonded to the measuring object with a dedicated adhesive. Strain occurring on the measuring site is transferred to the strain sensing element via adhesive and the resin base. For accurate measurement, the strain gauge and adhesive should be compatible with the measuring material and operating conditions such as temperature, etc. 2.2.2 Metal strain gauge The change of resistance in an electrical conductor due to the impact of mechanical stress, as discovered by Wheatstone, became the subject of study in the 1930s. A number of advancements were experimented and finally Ruge took a very thin resistance wire, stuck it in ...
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Principle of Strain Gauge

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PRINCIPLE OF OPERATION 2.1 Principle of Strain Gauges If external tensile force or compressive force increases or decreases the resistance proportionally increases or decreases. Suppose that original resistance R changes by ΔR because of strain ε, the following equation is set up.             △R/R= Ks.ε Where, Ks is a gauge factor, expressing the sensitivity coefficient of strain gages. General-purpose strain gauges use copper-nickel or nickel-chrome alloy for the resistive elements and the gage factor provided by these alloys is approximately 2. 2.2 Wheatstone Bridge A Wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component. The primary benefit of a Wheatstone bridge is its ability to provide extremely accurate measurements (in contrast with something like a simple voltage divider).   Its operation...
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Strain gauge Introduction

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INTRODUCTION   Strain gauge transforms an input energy (mechanical energy in the form of strain resulting from an applied force) into an energy output (electrical energy in the form of an induced voltage difference).   The induced voltage can be amplified, converted to a digital signal and read into a computer.   With the appropriate software and knowledge of the workings of a load cell, the resulting signal can be converted into a digital readout of the initial load. By using this instrument, the strain of an object can be determined. It is possible only when any object is placed on load cell, the strain is obtained and it is displayed in LCD display through Arduino Uno. 1.1 Physical Discoveries A strain gauge is a device used to measure strain on an object. Invented by Edward E. Simmons and Arthur C. Ruge in 1938, the most common type of strain gauge consists of an insulating flexible backing which supports a metallic foil pattern. The gauge is attache...
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