Use red crank to wind pink rubber band and launch the bird.
Two 4-bar linkages of a common crank are used to give the wings angular reciprocating motions. Green tranparent wings and tail are made of nylon film.
Pay attention to two facts caused by the simplification in this toy:
- Motions of two wings are not hundred percent symmetrical.
- The shape of red crank-shaft is not planar.
For more about this toy please see:
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/watch?v=0rAMh0hxqrs