Studying of elastic oscillations’ natural frequencies of manipulators in case of their reconfiguration

Ivan A. Rodin ^*
PhD in Technical Sciences, Russian State Scientific Center for Robotics and Technical Cybernetics (RTC), Technician, 21, Tikhoretsky pr., Saint-Petersburg, 194064, Russia, tel.: +7(812)556-36-92, This email address is being protected from spambots. You need JavaScript enabled to view it.

Ivan A. Vasilyev
PhD in Technical Sciences, RTC, Head of Laboratory, 21, Tikhoretsky pr., Saint-Petersburg, 194064, Russia, tel.: +7(965)766-00-37, This email address is being protected from spambots. You need JavaScript enabled to view it.

Received 18 February 2019

Abstract
The accuracy of the positioning of the actuation mechanism is a defining characteristic for handling robots. Manipulators, as spatial structures, have elasticities in their joints and links and, on this basis, have their own natural frequencies. In their various configurations, that is, at different values of the generalized coordinates, these natural frequencies may vary. The article is devoted to the study of the dependence of the natural frequencies on the current configurations of the manipulator. This article presents the thesis method for calculating the natural frequencies of the five-link manipulator, formula expressions of generalized forces, total kinetic energy and the resulting natural frequencies for the formula expression of those properties of the mechanism, based on the value of which the natural frequency is determined. The article also describes the graphical representations of the resulting frequencies when the manipulator changes its configuration over time and describes their dependencies based on the analysis of the mentioned formula and graphical representations. In conclusion the article presents a thesis expression of the dependence of the natural frequencies of the manipulator on its configuration and design features.

Key words
Robot, manipulator, oscillations, elasticity, natural frequency.

DOI
https://doi.org/10.31776/RTCJ.7104

Bibliographic description
Rodin, I. and Vasilyev, I. (2019). Studying of elastic oscillations’ natural frequencies of manipulators in case of their reconfiguration. Robotics and Technical Cybernetics, 7(1), pp.29-33.

UDC identifier:
621.865.8

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