To obtain the type synthesis of three-translational and one-rotational(3T1R)hybrid mechanisms
an efficient synthesis methodology is proposed based on fractal theory and topological graph. The major concept of this method is to transform the hybrid mechanism into linkage mechanism
whose main frame is determined by topological graph and whose links are composed of the assignment of kinematic pairs. Fractal theory is applied to the topological graph
and the permutation and combination of output displacement set and selecting suitable kinematic pairs are conducted to achieve the configuration diversity of hybrid mechanisms. The route rule for dealing with the topological graph is proposed
and the calculation rule of union-intersection-preserving for deriving the kinematic pair's output is presented. According to fractal theory and topological graph
the hybrid mechanism is classified into two types. Thereafter
a relationship model of hybrid mechanism and fractal theory is established
so the mechanical design and fractal theory are unified in mathematics and logic. Matlab is utilized in type synthesis of 3T1R hybrid mechanism
and one of the configurations is achieved
demonstrating the validity of the proposed methodology.
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references
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