Reaction forces in parallel mechanism pairs
Keywords:
parallel linkages, reaction forces, kinematic pairs, Denavit-Hartenberg transformation matricesAbstract
To calculate the links dimensions of a parallel mechanism, is necessary to determine the distribution of forces from its kinematic pairs. Also, the performance of such a mechanism can be evaluated after calculating the driving forces and reaction forces as well as the reaction moments from its kinematic pairs. To determine the force and moment distributions within the mechanism pairs, as well as the critical positions of the actual areas, the virtual mechanical work principle (J. Bernoulli, 1717) is used. For this, the links’ positions must be determined, meaning the sizes of the pair variables of all the mechanism kinematic pairs. The Denavit - Hartenberg transformation matrix method is used in this paper for both kinematic and kinetostatic analysis of the mechanism. The proposed method is applied to a multi-loop multi-degree-of-freedom linkage of the Stewart platform.
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