Four bar linkage 9b

A special case of the 4-bar linkage.
Input: pink crank.
Output: green crank rotating irregularly.
The unusualness: a working cycle of the mechanism corresponds 2 revolutions of the input. It happens because:
1. The sum of the lengths of the two opposite links is equal to the sum of the lengths of the other two links.
A + B = C + D
A: length of pink crank (=15)
B: length of green crank (=35)
C: length of yellow conrod (=40)
D: distance between fixed axes of cranks (=10)
2. There are measures to overcome dead positions (when green crank is in line with yellow conrod). For example, inertia of the green crank must be big enough.
Inventor files of this video:
http://www.mediafire.com/file/nftxzfnd3muy487/4Bar9bInv.zip

Видео Four bar linkage 9b канала thang010146