The aim of this work is an analysis of excess ties in handler closed kinematics and development of the structural synthesis procedure for self-aligning gears of industrial robots with parallel kinematics. The design of a structure flowchart of a gear without excess ties in the procedure offered is carried out by means of prototype mechanism updating and includes the following stages: the reveal and analysis of excess ties, excess ties elimination, correctness checkup of excess ties elimination. For the excess ties analysis and solution check-up a structural analysis is carried out. At that a handler is presented as a hierarchal structure described by some structural models. The ways for excess ties elimination: the substitution of one kinematic pair for another one with a higher number of mobility; the introduction of an additional link and one kinematic pair into a kinematics; the elimination from the kinematics an extra link with two kinematic pairs; the substitution in the kinematics a flat hinge parallelogram for a forward pair. There are developed some versions of structural diagrams of self-aligning handlers on the basis of an ortho- glide gear. The procedure offered allows defining the number and a type of excess ties in the kinematics of a gear, eliminating excess ties and forming structural diagrams of self-aligning gears with the conservation of basic operating properties on the alternative basis. The application of structural diagrams of handlers without contour excess ties is one of the ways to increase reliability and manufacturability of designs of industrial robots with parallel kinematics.

The work is devoted to improving the reliability and manufacturability of mechatronic machine designs with parallel kinematics by replacing statically indeterminable manipulators with statically determinable mechanisms. A technique is proposed in which the design of statically determinable manipulators of technological mechatronic machines with parallel kinematics is performed by modifying the structure of prototypes and includes three steps: identifying and analyzing redundant links, eliminating redundant links, checking the correctness of eliminating redundant links. To determine the number of degrees of freedom of the mechanism, identify redundant links, and verify the solution, the authors use the proposed methodology for structural analysis of parallel structure mechanisms. 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, which retain the basic functional proper ties of the prototype. To increase the number of self-aligning mechanism diagrams, the redistribution of mobilities and links within the connecting kinematic chain and between connecting kinematic chains is used. The proposed methodics allow 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 mechatronic machines with parallel kinematics.

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СТРУКТУРНЫЙ АНАЛИЗ МЕХАНИЗМОВ РОБОТОВ-СТАНКОВ С ПАРАЛЛЕЛЬНОЙ КИНЕМАТИКОЙВыполнен критический анализ существую-щих методик структурного анализа механизмов параллельной структуры, составляющих основу станков нового поколения с параллельной кинема-тикой. Разработана методика структурного анализа этих механизмов, основанная на декомпозиции ки-нематической цепи механизма с использованием наиболее подходящих структурных моделей. При-ведены примеры применения методики.Ключевые слова: роботы-станки с парал-лельной кинематикой, механизмы параллельной структуры, структурный анализ, структурные мо-дели, декомпозиция системы, композиция системы.A.K. Tolstosheev, V.A. Tatarintsev STRUCTURAL ANALYSIS OF ROBOT MACHINE MECHANISMS WITH PARALLEL KINEMATICS