TECHNIQUE OF STRUCTURAL SYNTHESIS OF STATICALLY DETERMINABLE PARALLEL STRUCTURE MECHANISMS OF TECHNOLOGICAL ROBOTS

TOLSTOSHEEV Andrey K., Ph. D. in Eng., Assoc. Prof., Associate Professor of the Department “Machine Parts”, Bryansk State Technical University, Bryansk, Russia, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.

TATARINTSEV Vyacheslav A., Ph. D. in Eng., Assoc. Prof., Associate Professor of the Department “Machine Parts”, Bryansk State Technical University, Bryansk, This email address is being protected from spambots. You need JavaScript enabled to view it.">Russia, This email address is being protected from spambots. You need JavaScript enabled to view it.

The article is devoted to improving the reliability and manufacturability of technological robots with parallel kinematics by replacing statically indeterminable manipulators with statically determinable mechanisms. The  technique of  structural synthesis of statically definable manipulators by modifying the structure of the prototype is proposed. The  procedure involves identifying and eliminating redundant links, checking the solution. To determine the number of degrees of freedom of the mechanism, identify redundant links and verify the solution, the authors use the proposed methodology of structural analysis. In structural analysis, a manipulator is represented by a  hierarchical structure and is considered as a parallel connection of elementary mechanisms with an open kinematic chain; as a kinematic chain consisting of leading and driven parts; as a set of links and kinematic pairs; as a kinematic connection of  the output link and the rack. The article implements the following techniques for eliminating redundant links: mobility increase in kinematic pairs; introduction of unloading links and passive kinematic pairs to the kinematic chain; exclusion of extra links and pairs from the kinematic chain; increase in mobility in some kinematic pairs simultaneously with the exclusion of other kinematic pairs that have become superfluous. The authors developed several variants of  structural schemes of self-aligning manipulators based on the Orthoglide mechanism. The  proposed technique allows to  determine the number of degrees of freedom of the mechanism, the number and type of redundant links, eliminate redundant links and, on an alternative basis, build structural diagrams of statically determinable mechanisms of technological robots with parallel kinematics.

technological robots, parallel kinematics, redundant links, statically definable mechanisms

1. Merlet J.P. Parallel Robots. Dordrecht, Springer, 2006. 417 p.
2. Reshetov L.N. Samoustanavlivayushchiesya mekhanizmy: spravochnik [Self-aligning mechanisms: reference book]. Moscow, Mashinostroenie Publ., 1991. 288 p.
3. Egorov O.D., Buynov M.А. Metod strukturnogo analiza mekhanizmov robototekhnicheskikh i mekhatronnykh ustroystv [Methods of structural analysis of the mechanism of robotic and mechatronic devices]. Mekhanika mashin, mekhanizmov i materialov [Mechanics of machines, mechanisms and materials], 2016, no. 2(35), pp. 15–22.
4. Kalendarev А.V., Lysogorskiy А.E., Glazunov V.А. Strukturnyy analiz mekhanizmov parallelnoy struktury s chetyrmya i pyatyu stepenyami svobody [Structural analysis of mechanisms of parallel structure with four and five degrees of freedom]. Izvestiya vuzov. Mashinostroenie [Proceedings of higher educational institutions. Маchine building], 2013, no. 3, pp. 7–10.
5. Аfonin V.L., et al. Obrabatyvayushchee oborudovanie novogo pokoleniya. Kontseptsiya proektirovaniya [Processing equipment of new generation. Design concept]. Moscow, Mashinostroenie Publ., 2001. 256 p.
6. Kong X., Gosselin C. Type Synthesis of Parallel Mechanisms. Berlin, Heidelberg, Springer-Verlag, 2007. 272 p.
7. Gogu G. Structural Synthesis of Parallel Robots. Part 1: Methodology. Dordrech, Springer, 2008. 720 p.
8. Byushgens А.G., et al. Strukturnyy analiz mekhanizmov parallelnoy struktury s krugovoy napravlyayushchey i shestyu stepenyami svobody [Type analysis of parallel structure mechanisms with circle rail and six degrees of freedom]. Spravochnik. Inzhenernyy zhurnal s prilozheniem [Hand-book. An engineering journal with appendix], 2014, no. 2, pp. 13–19.
9. Podzorov P.V., Bushuev V.V. Strukturnyy analiz i klassifikatsiya mekhanizmov parallelnoy kinematiki [Structural analysis and classification of mechanisms of parallel kinematics]. Mekhatronika, avtomatizatsiya, upravlenie [Mechatronics, automation, control], 2004, no. 10, pp. 42–49.
10. Glazunov V.А., Borisov V.А. Razrabotka mekhanizmov parallelnoy struktury s chetyrmya stepenyami svobody i chetyrmya kinematicheskimi tsepyami [Development of mechanisms of parallel structure with four degrees of freedom and four kinematic chains]. Problemy mashinostroeniya i nadezhnosti mashin [Journal of machinery manufacture and reliability], 2017, no. 5, pp. 3–12.
11. Tolstosheev А.K., Tatarintsev V.А. Strukturnyy analiz mekhanizmov robotov-stankov s parallelnoy kinematikoy [Structural analysis of robot machine mechanisms with parallel kinematics]. Vestnik Bryanskogo gosudarstvennogo tekhnicheskogo universiteta [Bulletin of the Bryansk State Technical University], 2017, no.   1(54), pp. 33–43.
12. Tolstosheev А.K., Tatarintsev V.А. Metodika strukturnogo analiza parallelnykh manipulyatorov selskokhozyaystvennykh robotov [Method of structural analysis of parallel manipulators of agricultural robots]. Nauchnoe obozrenie [Science review], 2017, no. 22, pp. 37–42.
13. Tolstosheev А.K. Teoriya stroeniya mekhanizmov: uchebnoe posobie [Theory of mechanism construction: educational manual]. Bryansk, Bryanskiy gosudarstvennyy tekhnicheskiy universitet Publ., 2001, 139 p.