Two-freedom seven-bar linkages with sliding inputs and output are especially compact as two-variable function generators. When two of the sliders, appropriately chosen, have parallel directions the method of identical link positions is shown to split up the synthesis of the linkage into that of a double slider and a slider-crank while as many as 11 precision points are obtained. © 1976.
Ramaiyan, G., & Lakshminarayana, K. (1976). Synthesis of seven-link two-freedom linkages with sliding inputs and output using identical link positions. Mechanism and Machine Theory, 11(3), 181–185. https://doi.org/10.1016/0094-114X(76)90044-6