A method for branch identification of planar six-bar linkages with sliding pairs

The identification of branch, motion defect and range of motion of the planar six-bar linkages with sliding pairs is an important indicator for motion characteristics of linkages. Firstly, this paper divides the planar six-bar linkages with two sliding pairs or three sliding pairs into four-bar chain or five-bar chain. B-ring in Euler's formula and trigonometric substitution method, the specific configurations (including branch points and dead points) of the planar linkages with sliding pairs in their limit positions, input and output relationship and joint rotation space are obtained. Secondly, this paper combines two chains and proposes a method for the branch identification of planar six-bar linkages with two or three sliding pairs. Finally, this paper verifies the proposed method with examples of planar six-bar linkages with two and three sliding pairs. The branches, dead points and the specific angles of joints in limit positions of the two mechanisms are calculated. The proposed method gives a convenient and effective way for the automatic branch identification of planar linkages with sliding pairs.