Not too sure how strange of an ask this is, but have any ideas on how to make a winged being with "legwings" similar to sharovipteryx, but is capable of flight? Thank you in advance!
in the process of looking up images to remind myself what a sharovipteryx is and how it moves, i found this tumblr post redesigning the pokemon Latios and Latias as a pair of sharovipteryx and it's amazing, I love this, shoutout to @alphynix
There's a weird little Triassic critter called Sharovipteryx, a lizard-like protorosaur with an extensive membrane between its long hind leg
anyway. so what you're asking is how to make a creature with those back-leg membrane wings but in a way that allows for powered flight instead of just gliding? powered flight requires some method of flapping, so as long as the muscles and joints are able to move that way, it should work out. for reference, here's an image of the sharovipteryx (artist: Dmitry Bognadov)
(image description: artistic depiction of two prehistoric flying lizards, seen from below. they have long skinny tails, short forelegs, and very long back legs with a triangular membrane over them, including a membrane between the knees and belly. end description)
their shape reminds me of a paper airplane.
hmmmm let's start by talking about how arm wings flap for powered flight, comparing their shape to these leg wings.
(image description: simple sketches of a bat wing, labeled "arm", and a sharovipteryx wing, labeled "leg". end description.)
going for the bat wing because they've also got a membrane. when bats fly, a lot of the motion is in the elbow (excluding the fingers for the sake of comparison here). each flap brings the wing to a full horizontal spread, and then it's drawn closer to the body and lifted at the elbow to bring it back upwards, more or less. not every flap folds all the way in! once a bat is in the air, it can usually flap in smaller motions to maintain its lift. this also depends on wing shape and size, as smaller wings require more frequent and deeper flapping while bigger wings are typically better for soaring and require less and more shallow flapping after takeoff.
the back leg wing is easy enough to spread out and flap downward, but i think the struggle comes from bending the knee for an upstroke. in this case, I believe a more flexible hip joint would allow for a better upstroke. or it would have to move more forward and then spread out. as a result, it may not have the same range of big flaps as a bat or bird, and i think it might resemble the way frogs kick their legs when they swim.
(animation description: very simplified sketch frames of a leg wing and an arm wing flapping. the arm wing goes all the way up and down for each flap, while the leg wing only comes in line with the body before it extends for a downstroke. end description.)
I do not dabble in animation very often and trying to do foreshortening on flapping wings is hard, so forgive the quality haha. but I couldn't figure out how else to illustrate what I was thinking of for the movement on the leg wings. may not be as efficient as arm wings when it comes to agile powered flight, but it would perhaps be enough to provide lift so the creature isn't just gliding.
hope that helps!