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where L is the number of linkages, J_1 is the number of full joints, and J_2 is the number of half joints. In this mechanism we have four linkages, three full joints (O2, A, and O3), and two half joints (O1, and D). Using equation one and the values given we have a degree of freedom of one.
Figure 3.1. Overall Drawings for the Kinematic Analysis
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