Bi-Wing Ornithopter

If a biplane was an ornithopter, would the wings flap together or out of sync? In this one the out of sync option is followed.

This monster was conceived during a sea-side holiday. During the morning beach comb, interesting sun-bleached bones presented themselves. I assume the body bones were originally the vertebra of a large fish but as they were found in isolation this is just a conjecture. The shape and size of the bones begged to be included in a monster. The rear body shape  is similar to that of a coelacanth , a very primitive large fish (Coelacanth - wiki). The body shape was defined by the 2 rear bones. The additional bone at the front of the monster was just for effect and I don't know what it represents. A hood ornament?  To enhance the primitive feel I have added a photo recently taken with expired Kodak Plus X (from 1988) in a Mamiya C330 and processed by a novice using old chemicals. I actually like the effect.

Analog black and white image of a bi-wing ornithopter

For this monster a variation on the woven grid  covering was implemented. In the cockpit area the covering is done with a finer black wire and a random pattern instead of approximate squares.  The end result is a more delicate finish, but I have not used it in subsequent models, yet. The ever-present crab claw face does make it's appearance. This makes it a creature instead of a device.

Example of fine wire random woven covering.

The movement of this monster is relatively simple. The wings are driven from cranks which are 180° apart. To try and get a symmetrical flapping motion there are 3 cranks. A central crank driving 2 push rods. Either side of this there are two cranks which are 180° opposed driving a single push rod each. These are connected to the wings and cause the upper and lower wing pairs to flap out of sync. The upper wing has an additional forward/backward motion. This is as a result of the shaft, around which the upper wing bearings rotate, being too long. I feel that the motion adds an element of interest, and have therefore not constrained it. This is one of those unintentional elements that come when using wire and not precisely machine mechanisms. If the wayward motion were stopped, then the relative movement between the pairs of wings would be more symmetrical, as initially intended by using the 3 cranks, but then again not all progress is as a result of intention. The nodding creatures head is driven from the central crank. Overall this is a fairly well balanced mechanism (compared with most of my other attempts). The whole lot is driven from a pair of lead cast wheels (do not feed this monster to kids), with a nose wheel added for balance. Generally I prefer a conventional undercarriage, but for this tail heavy monster this balances it out quite well.

View of motivating mechanism and monster 

The wing and tail surface covering is once again sourced from an old silk parachute. This is stretched, doped, and then a vein like pattern in black, yellow and red paint added. 

I have tried to create a relatively delicate monster this time (relative to the others).  These monsters only happen by chance (finding bones and dreaming, or a faulty mechanism which stays), and are more a result of seeing what bits from that beach walk present themselves as, rather than forcing your design on the material.  Initially chance should guide you, but sometime you have to take over so that you don't seem to lack direction.