Strain Gauge Tutorial: Selection & Tradeoffs

[Cyrus]

This is a very good little tutorial on how to use strain gauges and the tradeoffs found by using different sizes.

http://www.abacus.co.uk/jkcm/cache/fl0008816.jpg


http://signalprocessing.prosig.com/FatigueTesting/strain-gauge-close.jpg​

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http://www.vishay.com/strain-gages/knowledge-base-list/technotes-list/

This one is a particularly good general purpose strain gauge document:

Strain Gage Selection (TN-505)

 

[Cyrus]

I made a test specimen to measure uniaxial force. It's basically a long strip of .75mm aluminum. The area reduction at the test section was made such that adequate strain is available to make measurements. The filet was made to accommodate the reduction in area. The gauge length was such that the stress dissipates (due to Saint-Venant's principle) by the time it gets to the strain gauge. The test specimen was made on a end mill.

http://img187.imageshack.us/img187/2460/pict0381tn9.jpg

I probably should have chamfered the edges, but it isn't going to change anything and not worth the time and effort.