Structural Parameters and Displacement Equation of 7-Bar Goldberg Mechanism

doi:10.3901/JME.2020.17.082

Abstract

Abstract: At present, the closed-loop displacement equations of 5-bar and 6-bar Goldberg mechanisms are expressed by the outer angles of adjacent links. In order to express the angle relationship more clearly and intuitively between adjacent bars of multi-bar Goldberg mechanism, the displacement equations of 5-bar and 6-bar Goldberg mechanism were expressed by the internal Angles of adjacent bars. Through the analysis of 5-bar and 6-bar Goldberg mechanisms, a new 7-bar Goldberg mechanism was proposed, and its structural parameter equations and closed-loop displacement equations were expressed by the internal angles of adjacent bars were given. The closed-loop displacement equation and the input-output equations of the 7-bar Goldberg mechanism were verified by an example. The existing conditions of the 7-bar Goldberg mechanism were given. In addition to meeting the necessary constraint conditions of Bennett mechanism for side links and connecting link, it must also meet the condition that the frames with different virtual loops must be collinear. In theory, it broadens the concept and the applied range of Goldberg mechanism.

Key words: Goldberg mechanism, Bennett mechanism, 7R mechanism, close-loop displacement equation, type synthesis

CLC Number:

TH112

MU Dejun, ZHANG Yitong, LI Yanwen, HU Bo, LU Wenjuan. Structural Parameters and Displacement Equation of 7-Bar Goldberg Mechanism[J]. Journal of Mechanical Engineering, 2020, 56(17): 82-90.

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