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Fang Xinguo
School of Literature & Art,
Foshan University,
Foshan 528000, China
Zou Huijun
Guo Weizhong
School of Mechanical Engineering,
Shanghai Jiaotong University,
Shanghai 200030, China |
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SINGULARITY
ANALYSIS OF HYBRID
MECHANISMS USED
IN NEW METAL
FORMING PRESS*
Abstract: Firstly, based on the Jacobian matrixes relating the input speeds with the output speeds of mechanisms, a general method, which is used for solving the singularities of planar multi-loop multi-DOF mechanisms with sliding pairs, is presented. Secondly, four kinds of singularities of the hybrid mechanisms used in the metal forming presses are analyzed in detail by this method. Its five kinds of singular positions whose characteristics are discussed respectively are discovered. And three methods are proposed on how to avoid the singular positions of planar multi-loop multi-DOF mechanisms with sliding pairs. Based on the assemblability of planar single-loop N-bar kinematic chains or linkages, the geometry conditions are investigated and discovered to avoid the singular positions of the hybrid mechanisms. In order to verify aforementioned conclusions, a case is given in which the singular curves are plotted and simulated.
Key words:
Metal forming press Velocity matrix Hybrid mechanism Singularity |