Visually about redundant connections in mechanisms

The concept of redundant bonds began to penetrate into the theory of mechanisms and machines under the influence of the works of O.G. Ozol, S.N. Kozhevnikov and, mainly, L.N. Reshetov. However, in Russian textbooks on the discipline of the same name, the dominant position is occupied by the theory of general connections, in which there is no place for redundant connections: in the most respectable textbook on the theory of mechanisms (we omit "and machines"), all structural formulas of a mechanism do not contain the number of redundant connections. In contrast to general connections, redundant ones are real. Because of them, bфreakdowns are committed, up to accidents with human casualties. The concept of "redundant connections" should be well known to students of all specialties who are taught the disciplines "theory of mechanisms and machines", as well as "mechanics". In implementing the new approach, it is necessary to talk not only about possible combinations of bond numbers in kinematic pairs of the mechanism, which is sometimes done, but also to give examples of successful and unsuccessful substitutions of kinematic pairs with the required number of bonds. Examples of such substitutions are given in this article. Only the analysis of such examples can really teach how to construct "correct", as L. N. Reshetov put it, mechanisms that do not contain redundant connections. One of the results of this approach is the development and production of a model of a mechanism that allows you to demonstrate redundant relationships. A drawing of such a model is given in this article. Those interested can contact the author, who is ready to send drawings not only of a general appearance, but also detailing.
EDN: EFZFBZ, https://elibrary/efzfbz

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