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Productive activities require measuring systems as a key tool for manufacturing quality goods. Metal mechanical
industries develop their processes based on the control of a high precision fit between two pieces of a pressureassembled
product. Therefore, engineering materials are constantly subjected to resistance tests. Balance test equipment
and mechanical vibrations work under the principle of force measurements. The most precise stress measurement
methods are done with electromechanical devices known as load cells. They basically consist of a tiny electric resistor
that is adhered to a mechanical element that may be under stress. Cyclic stresses also directly affect the performance of
the measuring element including the resistance itself, which changes as the cyclic fatigue progresses (the measuring
element is a very thin coil with limited strength). In this research, we developed an optomechatronic load cell1 whose
operating principle is based on measuring the stress load applied to a mechanical element. The deformation causes a
reduction in the distance between the emitter and the receptor producing an electrical signal. It must be established that
the distribution of the light intensity varies between the emitter and the receptor due to the generated displacement. An
infrared emitter was adapted to the load cell whose signal was received by the receptor at the other end. The second
stage included a demonstration that the optoelectronic system is capable of measuring external stresses on a mechanical
element by using an indirect method of measuring stresses. Here we present the results from those experiments, which
include some adaptations on the mechanical element. We implemented a prototype sensitive to the deformation
produced by the mechanical element (load cell). As a result of the two stages, we plan to test the system in academic
and industrial applications. The third step in the research is to validate the optomechatronic load cell under the E74-065
ASTM Standard2 showing the results based on the resolution, sensitivity, and repeatability required by the standard.
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