Abstract
Unique strain gage based methods are developed to identify magnitudes and locations of multiple loads and the resultant of a distributed load on a slender beam. Four uniaxial strain gages mounted to the bottom surface of the beam create a force transducer capable of identifying the magnitude and location of a load inside the weight area, where the load can be a concentrated or distributed load. For the case of multiple loads separated by two or more strain gage locations, uniaxial strain gages forming multiple force transducers can still identify the magnitudes and locations of all the loads. However, this creates an ill-posed problem for loads separated by only one strain gage location. A new method has been developed using two shear gages mounted on the neutral axis of the beam, one on each side of a load, to identify the magnitude of the load in this case. A combination of two uniaxial strain gages and two shear gages, with one uniaxial strain gage and one shear gage at the same location on each side of a load, can be used to identify the location of the load. The strain gage based methods are experimentally validated on a prismatic beam with rest boundary conditions.
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Bednarz, E.T., Zhu, W.D. & Smith, S.A. Identifying Magnitudes and Locations of Multiple Loads and the Resultant of a Distributed Load on a Slender Beam Using Strain Gage Based Methods. Exp Tech 40, 15–25 (2016). https://doi.org/10.1007/s40799-015-0003-7
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DOI: https://doi.org/10.1007/s40799-015-0003-7