Alexander V. Orlov
Kostroma State University
Evgeny L. Pashin
Kostroma State Argicultural Academy
Orlov A. V., Pashin E. L. Improving the method of pendulum impactor verification in regard to energy loss due to friction. Technologies & Quality. 2023. No 3(61). P. 17–22. (In Russ.) https://doi.org/10.34216/2587-6147-2023-3-61-17-22.
DOI: https://doi.org/10.34216/2587-6147-2023-3-61-17-22
УДК: 677.017.4:620.171.3
Publish date: 2023-09-08
Annotation: Article presents an attempt to improve the method of pendulum impactors, such as tensile strength testing machine K-1 in regard to energy loss due to friction. Analysis of existing methods suggests a discre- pancy caused by ignoring the relationship between the energy loss caused by the tested material sample and that caused by friction. This introduces a systemic error and limits the applicability of such testing machines. Thanks to the modern rotational motion registration methods it becomes possible to estimate the intensity of friction at different points of the pendulum’s trajectory. This leads to a model of friction forces’ magnitude consisting of a linear combination of known motion parameters, such as angular coordinate, velocity and acceleration. The coefficients of this model can be determined using the non-negative variant of the least- squares method. This algorithm has been implemented into a software module for the K-1 testing machine.
Keywords: pendulum, friction, verification, inertial momentum, angular velocity, energy loss, K-1 tensile strength tester
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Author's info: Alexander V. Orlov, Kostroma State University, Kostroma, Russia, aorlov@list.ru, https://orcid.org/0000-0002-4995-3393
Co-author's info: Evgeny L. Pashin, Kostroma State Argicultural Academy, Kostroma, Russia, evgpashin@yandex.ru, https://orcid.org/0000-0002-5871-874Х