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Carl
06-27-2003, 03:04 AM
Hi, not sure why this thread was deleted. I would much appreciate any crits on this walk cycle. The idea is that it is carrying a heavy load as it walks across a wasteland. It's about a 900k file (quicktime) software used-Lightwave:

click here for animation (http://www.itg.uiuc.edu/people/burton1/beast_on.mov)

Kirt
06-27-2003, 03:48 AM
You're thread may have been deleted because ...Important- Artist, please state your software used, and also post a wireframe along with your final render or progressive paintings (if 2D). This is here to cut down on the redundant posts asking for them.We're watching this forum very closely so it's important that everyone read the General Rules (http://www.cgtalk.com/showthread.php?s=&threadid=70610) before posting here.

To critique your animation ... the back hind leg is the only one that really looks like it's moving properly. Still that's iffy considering it's obscured most of the time.

The other back leg has two weird lifts in the hip that don't coiencide with the placement of the creatures weight on the leg.

The front leg furthest away never leaves the ground and just slides back and forth.

The front leg closest to the viewer doesn't settle down before the weight of the creature moves forward.

That's just the most obvious errors. Fix those and then you'll probably get more critique to refine the other problems.

ed209
06-27-2003, 07:01 AM
I'm guessing your going for a heavy set type animal like an elephant. A large heavy animal like this actually doesn't have a standard quadruped walk cycle. An elephant for example will always have 3 legs planted at once. Here is a great example of what I'm talking about.

http://www.oaklandzoo.org/atoz/video8.htm

The cycle you have going needs allot more work. The feet are painfully slow and don't even feel like they touch the ground. The legs are also hyper extending as the creature steps. I would suggest looking for some reference material and study how similar creatures walk.

Carl
06-27-2003, 09:23 AM
Hey, thanks for both of your comments. That's a really interesting point about 3 feet on the ground. Hadn't thought of that at all. Very helpful and instructive comments. I'll see what I can do. Any more are welcome of course.

CarmineRedrum
06-27-2003, 08:35 PM
I agree with the previous statement about making this look more like an elephant. However most of the source material I found doesnt adhere to the statement that an elephant will ALWAYS have 3 legs planted. For a great 4 legged walk cycle referrence go to this page (http://www.freetoon.com/prestonblair/02-charactermov/pages/120.html) .

I know its been posted before but the online version of Preston Blairs Cartoon Animation (http://www.freetoon.com) is a great referrence for animators of any skill level.

aazimkhan
06-28-2003, 06:00 AM
Frist of all I would suggest buying the ANIMATORS SURVIVAL KIT by Richard Williams, amazing book.

If i were to do such a walk cycle. I would Animate the front legs normally like a humans leg, and then i would animate the rear legs , maybe like a dinosaurs leg?

Try animating them seperately, front, then later the rear - i dont know but right now they look off-sync.

Carl
06-30-2003, 07:24 AM
Ok, I tried to take into account many of your suggestions. I animated the two front legs first, then did the back ones. I also tried to add a greater sense of weight to the steps. Let me know what you think.

(quicktime/1.5 meg)

click here for version 2 of animation (http://www.itg.uiuc.edu/people/burton1/beaston2.mov)

CarmineRedrum
06-30-2003, 04:50 PM
It seems to me that the upward movement of the body is out of synch with the movement of the legs. Its hitting its extreme before the next leg leaves the ground. This is causing the legs that are about to step to fully extend and lock then then bend and lift. Also, the weight downward may be a bit too jerky.

Looking at the large piece on the creatures back made me notice that your side to side torso rotation gets pretty static as the creature moves along. You could adjust your tangents to correct that.

What makes it look even more odd is that they dont lift until weight is bieng shifted to them. While its good for the weight to shift just before the feet are fully planted, your weight is already there before the leg leaves the ground.

As far as the legs go they are a bit difficult to critique with the torso movement as it is. There are a few places where the knee joints lock and pop but I think that has alot to do with the torso. So maybe work with that a bit more then repost so we can pay attention to the legs.

aazimkhan
06-30-2003, 05:02 PM
Here are the things that i notice:
- He weight transfer right-left is too much and happening fast.
- Also the rotation of the heavy object on his back is too much, thats because you are shifting the weight
- His steps are too wide, make them smaller
- I think when he is lifting himself, there is some sense of weight, but he comes down really quick and loses sense of weight.

Another thing i notice is, your whole character has ONE COG!. I think he should have indvisual COGs for front and rear legs.

Carl
06-30-2003, 09:13 PM
These critiques are very good/useful. Thanks all. CarmineRedrum, could you perhaps rephrase what you mean when you say

It seems to me that the upward movement of the body is out of synch with the movement of the legs. Its hitting its extreme before the next leg leaves the ground. This is causing the legs that are about to step to fully extend and lock then then bend and lift.

WHat do you mean by "its extreme" and "fully extend"? Extend forwards? Sorry if I'm missing something obvious.

What makes it look even more odd is that they dont lift until weight is bieng shifted to them. While its good for the weight to shift just before the feet are fully planted, your weight is already there before the leg leaves the ground.

Do you mean that the torso shifts all the way to the character's left before its left front leg leaves the ground?

CarmineRedrum
07-01-2003, 07:20 PM
Yeah sure...Ill try to explain it better. Sorry it was hard to follow I was typing fast.

What I mean about the upward movement is that the torso is at the highest it goes when the foot is already touching the ground. So if the left side is stepping forward, the left rear foot touches the ground, the torso continues up for a few frames...then lowers. Im guessing from the rotation of the legs that you have IK set up on them. So whats happening is you plant the left rear foot, but the torso is still moving up, so the knee straightens out instead of bending. And finally a few frames later the torso drops to put weight on the leg. Its not as noticable on the front legs as it is rear.

What you could try to do is leave the legs as they are...but make the torso hit its highest point a little sooner. So that its already moving down when the next foot or feet are about to hit the ground.

Do you mean that the torso shifts all the way to the character's left before its left front leg leaves the ground?

Yes...but the more I look at the animation the more I think this could be solved by fixing the problem I mentioned above.
.

Carl
07-07-2003, 01:27 AM
Ok, here's the update. Let me know what you think. Thanks for your useful comments.

(1.5 meg/quicktime)

version 3 of animation (http://www.itg.uiuc.edu/people/burton1/beaston3.mov)

SDIT
07-07-2003, 01:41 AM
hey
i don't know if anybody has pointed this or not (sorry i haven't read all the posts throughly) But it seems like you are simulating the movement by sliding the legs backwards instead of pulling the creature foward. That looks weird. You might be able to pull it off but right now it does not look good. It is noticeable.
Your front left knee is snapping a little too. If you check out both of your front legs you will notice you have animated them differently. The one on the right doesn't snap. Check out the rythm too, i am pretty sure the whole cycle is irregular. Check out your extreme positions inbetween the keyframes.
Good luck. Cool creature.
cheers

stib
07-07-2003, 07:04 AM
when the legs are fully bent the keyframe should have more tension. At the moment they just sortof hit the bottom and start straightening up again, which makes the movement look very hard, almost like when the suspension of a car bottoms out. As the leg bends it should slow to a stop and then slowly start straightening. This will help give the idea of weight. The walk is really improving though.

SteveDavy
07-07-2003, 09:38 PM
I think you need to practice your cycle with something that's maybe easier to animate -- a quad walk cycle isn't easy and this is a weird looking creature that is only going to make it much harder. I think this would be a difficult animal for an accomplished animator to work with. Try getting a model of a horse or simply make your own stick figure quad to practice with first.

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