EM-106 | Strain Gauge Apparatus

Strain gauges are used extensively in sensor systems to detect forces, moments and deformations. The experimental unit provides a wide-ranging introduction to the fundamentals of measurement by strain gauges. Three test specimens for tension, bending and torsion are each fitted with four strain gauge measuring points. The strain gauges are wired in the full bridge. The specimens are loaded incrementally allowing for the strain reading to be sequentially monitored. The specimens can be inserted quickly and precisely into the frame. The strain gauge measuring range is protected by a Plexiglas cover, which also makes it clearly visible for inspection purposes. The measuring amplifier supplies the bridge supply voltage, and displays the load-dependent “bridge detuning” digitally in voltage values. The digital display also features a zero balancing function to allow for any preloading.

Learning Objectives

• Fundamentals of measuring with strain gauges
• Strain gauge types and application techniques
• Calculation of the mechanical deformations under tension, bending and torsion
• Correlation between mechanical strain and electrical resistance in a strain gauge
• Determination of the modulus of elasticity for various materials from the measuring data of a tensile test