i3 = n3/nc = (Z3 – Z1)/Z3
i2 = n2/nc = (Z2 - Z1)/Z2
nc: velocity of the blue crank.
n2: velocity of the green gear, its tooth number: Z2 = 50
n3: velocity of the yellow gear, its tooth number: Z3 = 20
Z1 = 24, tooth number of the fixed orange gear.