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Anybody have advice/ animating walk cycle???
Posted: 25 August 2012 02:53 PM   [ Ignore ]   [ # 31 ]
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head wax - 25 August 2012 06:28 AM

don’t know Joe smile

Well then, I’ll help you. I strongly suspect the answer is “yes”. If your feet are sliding, then either your IK targets are moving, or the “attraction” of your IK rig to the target is not sufficient. In some applications you can change that attraction, but I recall in Carrara you can’t. But it doesn’t matter because the attraction is very high. Which is good in this case.

So that leaves the only possibility being the IK goals moving when you don’t want them to, which then slides the feet. So if you want the feet to stick, you need to make sure the goal is in exactly the same XYZ position in each frame.

Also, you need to make sure that, between frames, the interpolated motion is flat or “linear”. Otherwise, the program will throw a curve in there (“Bezier” or whatever), and make the goal move between frames, sliding the feet. If you want goals to stick, use linear interpolation. That’s a pretty common technique across software applications, especially with feet. Check the Graph for the XYZ position of each goal and make sure there’s a flat line between frames, and both keyframes are the exact same position.

I suppose I could infuriate everyone once again by saying that these are the kinds of basic animation principles and techniques you read about in a book on basic computer animation principles, but probably won’t see in any software-specific tutorials that folks here seem to love so much. But I won’t.

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Posted: 25 August 2012 05:06 PM   [ Ignore ]   [ # 32 ]
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Well then, I’ll help you

Thanks for your kindness Joe.
Have a good weegend!

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Posted: 26 August 2012 12:37 AM   [ Ignore ]   [ # 33 ]
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In addition to what Joe wrote - floating and foot slippage is also caused by using the traditional walk in place technique, then not matching length of stride and distance covered to the foot movement.  Which is why I incorporate forward movement into the cycle.

With so many excellent tools as mentioned before available, doing your own walk cycle is really just an exercise.

For those who want to, Mark Bremmer has done an excellent Carrara-specific tutorial on a cycle for a spider, see http://www.markbremmer.com/3Bpages/DAS08spider.html

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Posted: 26 August 2012 03:24 AM   [ Ignore ]   [ # 34 ]
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Okay, I may have given Carrara a bit of a bad rap that isn’t really deserved when I used an example of knee bending when you lower the hips. Turns out that’s pretty easy to do, as well as maintaining the feet/toes planted flat on the ground throughout the motion.

Below is an animation of H4 (the first time I’ve ever used the guy…anyone else think he’s really weird looking?) doing a simple squat, then balancing on each leg. What’s normally done automatically using expressions had to be done with FK (counter-rotating the spine to maintain balance), so since Carrara doesn’t have expressions the other examples I gave are still legit. But knee bends and foot planting are do-able.

The way I did it is to add an IK modifier to each shin and each toe, and then add three IK goals for each leg, and assign one each to the shin IK, the toe IK, and the foot IK. Took a bit of tweaking to figure out the best location for the goals, but once you’ve got that it works okay. Though I did have to remove rotation limits for the foot as I recall to keep the feet flat on the ground. 

http://youtu.be/IQNnuT02WPE

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Posted: 26 August 2012 08:25 AM   [ Ignore ]   [ # 35 ]
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JoeMamma2000 - 26 August 2012 03:24 AM

Okay, I may have given Carrara a bit of a bad rap that isn’t really deserved when I used an example of knee bending when you lower the hips. Turns out that’s pretty easy to do, as well as maintaining the feet/toes planted flat on the ground throughout the motion.

Below is an animation of H4 (the first time I’ve ever used the guy…anyone else think he’s really weird looking?) doing a simple squat, then balancing on each leg. What’s normally done automatically using expressions had to be done with FK (counter-rotating the spine to maintain balance), so since Carrara doesn’t have expressions the other examples I gave are still legit. But knee bends and foot planting are do-able.

The way I did it is to add an IK modifier to each shin and each toe, and then add three IK goals for each leg, and assign one each to the shin IK, the toe IK, and the foot IK. Took a bit of tweaking to figure out the best location for the goals, but once you’ve got that it works okay. Though I did have to remove rotation limits for the foot as I recall to keep the feet flat on the ground. 

http://youtu.be/IQNnuT02WPE


Just to clarify, Joe, when you say IK goals, are you referring to target helper objects?

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Posted: 26 August 2012 09:08 AM   [ Ignore ]   [ # 36 ]
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I am of the opinion that, if you want to do animation (cartoon), the manual way is required. There are some principles that you have to go by, like: timing, squash and stretch, anticipation, overlapping motion, etc. It is an art, like drawing. But if you want to do realistic motion, then motion capture is peobably the best way. Sometimes, you have to mix both. Here I have roughly used the manual way with Gaba’s IK “Genesis helpers” (see download link) for the feet, and for the upper part of her body I have used a Mixamo mocap. She’s supposed to be arthritic.

http://youtu.be/14OGwyaIALI
https://dl.dropbox.com/u/11970483/GenesisHelpers.zip


Some people have mentioned the Poser walk designer, which is pretty good, although somewhat mechanical. I used it in the past. But lately, I found that iClone’s animation tools are better than Poser. Although I don’t use iClone for anything else, I found that it has some pretty sophisticated animation tools. I has Human IK. You can modify your character’s walk better than in Poser. You can have your character’s feet stick to the ground at all times. You can have your character walking up and down a hill on a motion path. Here is a woman walking down a hill. If you have 3dxchange pipeline, you can import AND export animation back and forth between iClone, Daz Studio, Carrara, 3dmax, etc…

  http://youtu.be/825IWk7snTk

 

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Posted: 26 August 2012 01:08 PM   [ Ignore ]   [ # 37 ]
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What route did the figure walking down the hill take to get into Carrara - I ask because the ankles cross through each other - typical of an anim made in Studio and imported to Carrara.

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Posted: 26 August 2012 01:12 PM   [ Ignore ]   [ # 38 ]
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argus1000 - 26 August 2012 09:08 AM

I am of the opinion that, if you want to do animation (cartoon), the manual way is required. There are some principles that you have to go by, like: timing, squash and stretch, anticipation, overlapping motion, etc. It is an art, like drawing. But if you want to do realistic motion, then motion capture is peobably the best way. Sometimes, you have to mix both. Here I have roughly used the manual way with Gaba’s IK “Genesis helpers” (see download link) for the feet, and for the upper part of her body I have used a Mixamo mocap.

Argus1000, you mention timing and squash and stretch and anticipation and overlapping motion, but you don’t use them. With all due respect, the video of the woman going upstairs shows no sense of weight or natural movement.

One of the most common mistakes used by beginning animators is forgetting to move the hips, which are the center of human motion. And especially when going upstairs, there is a lot of hip motion. Arthritic or not, you must move your hips and exert effort when going upstairs. Which means the motion must have a sense of labor and effort, and the motion of the body would seem to be dragging. Especially if someone is feeling pain, the motion would be slow and labored.

One technique you can use to get a feel for how to animate is to exaggerate. Think of an extreme version of a slow, labored walk up a steep flight of stairs, with a person who is very tired. Think of how your weight would shift, how you would maintain balance, how your hips move, how your spine counter-rotates with your hips to maintain balance.

There is a lot going on when you move, and it is very complicated. It takes a lot of thought and practice. You can have software try to do it for you, but usually you’re pretty limited in having to accept what the software provides.

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Posted: 26 August 2012 02:07 PM   [ Ignore ]   [ # 39 ]
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JoeMamma2000 - 26 August 2012 01:12 PM

[Argus1000, you mention timing and squash and stretch and anticipation and overlapping motion, but you don’t use them. With all due respect, the video of the woman going upstairs shows no sense of weight or natural movement. .

I never said I was an animator. I am a realistic man. I always use motion capture. Yesterday, I couldn’t find a realistic mocap of a woman going up the stairs. The feet were always off. So I decided to use Faba’s Genesis helpers IK features to make my character go up the stairs in a precise fashion. I found it easy to use. So I decided to share my discovery.

You seem to have something against that. I don’t know why. Besides, I said: “Here I have ROUGHLY used the manual way”.

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Posted: 26 August 2012 02:13 PM   [ Ignore ]   [ # 40 ]
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Roygee - 26 August 2012 01:08 PM

What route did the figure walking down the hill take to get into Carrara - I ask because the ankles cross through each other - typical of an anim made in Studio and imported to Carrara.

Thank you for reminding me that her ankles go through each other. Very easy to correct. I could have corrected in Daz Studio or in Carrara in two minutes.You’re right, because when I made the animation in iClone, the ankles didn’t go through each other. It must’ve happened when imported in Daz Studio.

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Posted: 26 August 2012 02:33 PM   [ Ignore ]   [ # 41 ]
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argus1000 - 26 August 2012 02:07 PM

So I decided to share my discovery.

You seem to have something against that. I don’t know why.

Relax, I’m not trying to attack you. I’m trying to help you and others who might want to improve their skills. If you don’t want to improve your skills then just ignore what I’m saying. If you do want to improve your skills with animating, then consider what I’m saying.

I did a quick and sucky, and slightly exaggerated demonstration to show a single cycle of walking up some stairs. I slowed it so you can see the details. It isn’t that difficult if you just understand a few simple concepts. And if you do it manually it might save you some money, and might actually be fun.

What you need to consider is weight and balance. Notice in the video how she first moves all of her weight to her right leg as her right foot steps onto the lower step. Once her weight is over the right foot, her right leg then extends and lifts the body up, raising it for the first step. She then balances for a brief moment on her right leg as her left foot is up in the air, dragging behind, until it reaches the second step. Then the cycle repeats. And once you have that simple motion laid out, check it from the front and sides to make sure it looks natural. Often with animating it can look okay from the side, but something isn’t quite right, then look at it from the front and it becomes obvious that the abdomen needs to rotate or something like that.

Also notice how the hips move, and the abdomen and chest counter-rotate to maintain balance. With a little practice you can work out a draft motion like this in maybe 1/2 hour or so.

http://youtu.be/n9gkNCX_8Hw

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Posted: 26 August 2012 02:54 PM   [ Ignore ]   [ # 42 ]
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And here’s the same motion from the rear so you can see the exaggerated hip motion. Hip motion is extremely important in any character animation, as is the motion of the abdomen/chest/spine. If you aren’t animating all of those things, you may be leaving out some very important stuff…

http://youtu.be/j9lmia7jGvY

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Posted: 26 August 2012 04:15 PM   [ Ignore ]   [ # 43 ]
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Okay dokey it looks like i got enough info here to get me started. THANX to you all. My first love isnt character animation it is rather modeling and scene layout and stuff. Ill give it a try…..

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Posted: 26 August 2012 05:01 PM   [ Ignore ]   [ # 44 ]
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Some good info in this thread.  Just giving a link.. Mark Bremmer has a walk cycle tutorial for a multi leg walk cycle (spider). just FYI http://www.markbremmer.com/3Bpages/darkarts.html

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Posted: 26 August 2012 11:19 PM   [ Ignore ]   [ # 45 ]
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Hi argus - I wasn’t being critical, just very interested.  Some time ago when I was trying to get some bvh working in Carrara, I tried taking them through DS.  The walks would work perfectly in DS, but in Carrara that ankle-crossing would happen.  Used BVHacker to fix, but that also had problems because the skeleton in BVHacker doesn’t have flesh, so it is difficult to judge just how much to adjust the bones by.

This doesn’t seem to be a problem taking them through Poser, although I haven’t done that many, so can’ say for sure.

Then the realisation hit me - why on earth do we amateurs try to get real looking humans acting and moving like real humans?  Not even Pixar tries to do that.  So for me anyway, humans are for stills and cartoon characters are for animation.

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