Adjustable four-bar linkages for multi-phase motion generation

When the position of a driven side-link fixed pivot is adjusted, multi-phase motion can be generated by the same four-bar linkage. An optimal synthesis method of adjustable four-bar linkages for multi-phase motion generation is put forward in this paper. The closed-form synthesis procedures of driving and driven side-links are presented. The requirements for fixed pivot positions, no branch defect, crank existence and link length ratio are taken as constraints, and the transmission angle is aimed to be optimal when adjustable four-bar linkages are synthesized. A modified genetic algorithm is employed to seek the global optimal solution. Results of two synthesis examples verify the effectiveness of the proposed method.