How do the wheels at the base help ? You should try to explain with more labels on your drawing to make things more clearly.
The sketch on the duck is unclear as you didn't show what happens when the wheels are moving and how the mechanisms work. Also didn't mention is movable pivot or fixed pivot.
The drawing is not clear enough because there is no labeling so I do not understand what is the crank connected to (besides getting connected to the wheels).
you did not specify where exactly and what kind of view you are looking at towards the mechanism.