animating a bird flight cycle tutorial

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Equalrights4animals
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Joined: Sat May 10, 2014 10:26 pm

animating a bird flight cycle tutorial

Post by Equalrights4animals »

This is my tutorial on how to animate a bird flight cycle in anime studio. Bird flight can be difficult to animate in a 2D program like AS, since the perspective of the wings changes as they flap. Here is how I animate a flying bird in profile view in AS.

1. Draw and rig your bird with the wings in the up position. Each wing should be comprised of two layers, one for the "hand" of the wing and one for the "arm" of the wing. Hide the scenes between the two layers with a patch layer. Try to keep the wings fairly simple.

2. Create a new action and go into the timeline for that action.

3. For the downstroke, go to the frame where the wings will be at their extreme down position. Select all the layers in the first wing by holding shift, and using the translate layer tool, set the Y scale to -1. Also rotate the layers so that the wing tip is pointed not just down but down and slightly forwards, as this is how real birds fly. The slower the bird is flying, the more extreme the forward angle will be. For some birds, the upper and under surfaces of the wings are a different color. If you want your bird to be like this, click “allow animated layer effects” in the layer settings for the wing layers (not counting the patch layer). Change their fill color when the Y scale goes from positive to negative, and fiddle with the interpolation and key frames so the color change is sudden and not gradual. The wing “hands” can be angled up slightly on the downstroke for added realism.

4. Now it’s time to do the upstroke. The upstroke should be faster than the downstroke, since a bird’s wings have more surface area on the downstroke, which slows down the downstroke due to air resistance. For the upstroke, go to the up extreme frame, and set the Y scale of the inner wing and outer wing back to 1. Real birds angle their wing “hands” down significantly on the upstroke, and this movement is especially extreme for small birds. To give this effect, keep the Y scale of the wing “hand” at -1 (what its scale was at the wing’s extreme down position) for a while as the Y scale of the “arm” of the wing starts to move back towards 1. The longer you delay the beginning of the wing “hand’s” scale change, the more angled down the wing “hand” will appear. Make sure the wing “hand” and “arm” appear connected at all times, and move the patch layer as needed. Once again, if the upper and under surfaces of the wing are a different color, now change the fill color back when the Y scale of the layer (“arm” or “hand”) goes from negative to positive. Again, the color change should be sudden.

5. Repeat steps 3 and 4 with the second wing, or if you’re feeling lazy you can just duplicate the first wing, which will also duplicate the animation that goes with it. Remember that when you’re seeing the undersurface of the first wing, you are seeing he upper surface of the second and vice versa, so inverse all color changes for the second wing.
Here is an animation I did that involves flying birds: https://www.youtube.com/watch?v=d86emiv ... FZeMH92gTg
Here are some reference pictures from flight cycles that I have animated in AS Pro 10.

Extreme up positions at the end of upstroke:
Image Image

Extreme down positions:Image Image

Wings rotating down: Image Image

Wings rotating up: Note how the wing “hands” are angled down. Image Image

6. Add body movement. A bird’s body and legs counter the wing movement, moving down slightly as the wings move up and moving up as the wings move down. This movement is subtle compared to the wing movement, but the leg movement becomes more noticeable if the bird is exerting a lot of effort in flight, such as when a bird is carrying something heavy. The head and tail counters the chest movement, although the head and tail movement is more subtle than the chest movement. The tail also spreads out as the wings rotate down. I control the tail spread with a simple smart bone action. For more detailed info on animating bird flight in general, visit this link, which is where I got much of my info for my tutorial. http://www.brendanbody.co.uk/flight_tutorial/
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negroclarito
Posts: 123
Joined: Sun Feb 28, 2010 6:38 am

Re: animating a bird flight cycle tutorial

Post by negroclarito »

Thank you for sharing... :D
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