Synthesis of a Type of Self-motion Mechanisms and the Dimensional Characteristic of Ratio Based on the Construction of Cognates

doi:10.3901/JME.2018.19.041

Abstract

Abstract: The research focuses on the 6-SS type self-motion mechanisms with regular triangle platforms. From the viewpoint of the construction of cognates, the synthesis and the dimensional characteristic are studied. Based on the characteristics of rotation and translation, the conformal geometric algebra model of a spatial SSC mechanism is established, and the mapping relationship between the kinematic parameters and dimensions is analyzed. According to the perpendicular projection of the SSC mechanism at the highest position, a cluster of 3-SS/C mechanisms with the same mapping relationship as SSC mechanism is proposed. Then the construction essence of the 6-SS type self-motion mechanisms with regular triangle platforms based on cognates and configuration conditions are revealed. Through the dimensional transformation of the 3-SS/C mechanism cluster, the cognate mechanism of a known 3-SS/C mechanism is designed, and the geometric regularity of the designed point is expressed. The geometric method for the mechanism synthesis is proposed. Furthermore, the ratio of dimensions in this type of mechanisms is deducted based on the obtained geometric regularity. The research not only yields up the variety of cognate mechanisms, but also provides a new viewpoint for topological structure synthesis of robot mechanisms regarding to the dimensional characteristic of ratio.

Key words: cognates, dimensional transformation, mechanism synthesis, ratio, self-motion mechanisms

CLC Number:

TH112

SHEN Chengwei, HANG Lubin. Synthesis of a Type of Self-motion Mechanisms and the Dimensional Characteristic of Ratio Based on the Construction of Cognates[J]. Journal of Mechanical Engineering, 2018, 54(19): 41-48.

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