The yellow gear (radius r2 = 30) is fixed to the connecting rod. The green gear (radius r1 = 60) is not fixed to the pink input crank.

Crank length: R = 60 Connecting rod length: L = 90 (r1 = L – R)

The green output gear irregularly rotates (with dwell) 2 revolutions when the pink crank rotates 1 revolution in the opposite direction.