User`s guide
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that defines the continuous waveform). In the case of a set of n values
, the RMS
is given by:
The RMS of a sine wave function is given by:
The RMS value of the vibration altitude, velocity and acceleration can be calculated by
Eq.61 with the peak values provided by Eq.57, Eq.58 and Eq.59.
2.3.4 Determining the Elastic Modulus
Recall the expression of natural frequency in rad/sec in eq.22:
Since we have
, the first frequency in rad/sec can be expressed as:
Therefore, the elastic modulus can be given by:
2.4 Basics of Strain Gages
2.4.1 Operating Principle and Application of Strain Gages
Strain-gauge sensor is one of the most commonly used means of load, weight, and force detection. Strain
gauges are frequently used in mechanical engineering research and development to measure the stresses
generated by machinery, and in Aircraft component testing to structural measure stress of members,
linkages, and any other critical component of an airframe.
A strain gauge operates on the principle that the electrical resistance of a wire changes when the length of
the wire varies. It is used for measuring deformations in solid bodies. The strain experienced by the
Eq.60
Eq.61
Eq.62
Eq.63