PDA

View Full Version : Robot Walk Cycle


Animatter
07-19-2008, 02:28 PM
Hi I just 'finished' this walk cycle,

As far as I can tell the knees are a bit jerky and some of the follow though doesn't seem to add up physically, I may have offset some of the overlap too far, or maybe not, I'm quite happy with how it looks but Its got a little way more to go in my opinion, before the whole body moves in perfect harmony.

If anyone can put it into more useful and objective terms than me, I would be most grateful.

CLICK HERE (http://www.angelfire.com/mattjmit/Boris.html)

thebeesneeze
07-20-2008, 03:06 AM
Looking really good!

a couple of small things that caught my eye straight away . . .

- like you said the ik pops on the knee are quite distracting.

- the arm swings are nice, but they really need some 'hang time' when they hit their extreme's. especially when they go back. right now their timing is quite even.

- the hips in the front view have a lot of movement. Theres nothing wrong with their movement, its just quite independant of the rest of the upper body. It might be nice to try and counter rotate the spine to help blend this hip rotation through to the body more.

any way just a couple of thoughts, looking great though!

Nucleo
07-20-2008, 06:12 AM
Hey man

This looks very good already i like the hips rotations you got in there they show real weight.

Try fixing the poping knees and check the arcs of your wrists from the front view espiecially when the arms are at the highest point which should be (if iam not mistaken) the squash pose.

Also check the back feet in the cycle when its lifting up they should push the body and hips forward instead now it feels to me that the hips lead the action. Very nice work and keep it up iam doing walks myself now and they hard so keep working on them.



Cya

Animatter
07-21-2008, 01:14 PM
Thanks Both of you! theres some realy geat stuff to be getting on with from what you've both written there, I'll post some updates when I've tweaked him a bit more.

There is one thing I would like to ask though, what is the root of my problem with the knee jerks? I had it worse before so I tried to fix it by rolling the foot forward less at the back of the down pose, this has helped a bit, but as you can see I'm still having throuble.


Also heres something I knocked up the other night, It's the first run cycle I've done:

http://www.angelfire.com/mattjmit/Balltail.html


Thanks again.

Matt

thebeesneeze
07-21-2008, 01:26 PM
Your IK controller is moving past the point of full extension on the leg. A frame or two later the knee 'pops' back into place as the ik constraint kicks back in and bends the leg again. A simple way to fix this I find is to never let the IK take the leg to 'full' extension. drop the pelvis down on its highest positions and the whole thing may go away. .

As far as your other anims go, they look great!!

SheepFactory
07-21-2008, 02:55 PM
To add to what Shawn said, I think the hands are too relaxed for his attitude. He looks like he is pissed yet the hands look like he just had a 2 hr massage session and is relaxed. A lot of walks have this default hand pose but most of the attitude lies in the hands. Spend some time with em and your animations will be much better!

great job otherwise.

switchblade327
07-23-2008, 11:24 PM
To add to what Shawn said, I think the hands are too relaxed for his attitude. He looks like he is pissed yet the hands look like he just had a 2 hr massage session and is relaxed. A lot of walks have this default hand pose but most of the attitude lies in the hands. Spend some time with em and your animations will be much better!

great job otherwise.

Along these lines, while the fingers are loose and relaxed, the thumbs are strangely erect, most noticable from the side view.

It might also be nice to add just a hint more of rotation/bob on his head. His torso and hips have a lot of weight but the head feels kind of inconsistent to me with it's purely side to side motion.

Also, it'd be nice to see some secondary action on those detached eyebrows. The shouldn't be so still for not being attached to anything.

Looks really nice though! This are fairly minors nitpicks (the knees mentioned before being the biggest issue).

Animatter
07-24-2008, 10:01 AM
cool, I did think it was plain lazy of me to have left the thumbs. It wasnt so much lazy because I didnt want to animate them, it was more that I had got impatiend and wanted to see it all rendered, then I was too damn lazy to go through rendering again, so anyway that was pretty dumb. The thumbs and the head should be pretty easy to fix, its just a case of doing them, but the knees are killing me Im getting all kinds of issues, If any of you guys could give me a list of techinical things that you have to look out for when working with the knees, I would greatly appreciate it. I'm going to be working on them today so ill post video of some of my usual problems so you maybe tell me what im doing wrong.

I tried not extending the legs too far but then i got a different problem with the knees that I always seem to get so ill show it later when I have a quicktime.


Also it was a decision I made not to do anything to the face since it was on such a short loop , but ill try some things out if you think it could look better.

brainoise
07-24-2008, 04:28 PM
It looks pretty good, good job. Just a couple of comments, and sorry if someone already broght this up. Watch out for the knees popping, it's happening a lot. Also, you might want to have more side to side movement just to kkep the balance, so that when the robot is on one leg his body looks totally balanced on that one leg. Keep at it...

switchblade327
07-24-2008, 06:28 PM
Also it was a decision I made not to do anything to the face since it was on such a short loop , but ill try some things out if you think it could look better.

The face itself is fine, it's just the floating eyebrows complete lack of movement that bother me. I'm not suggesting you make the eyebrows more emotive; just have them bounce a little with the rest of his body.

As for the legs, it's just about finessing them frame-by-frame til they look right. There is no quick fix to keep legs from hyperextending, unfortunately.

mattjmit
07-24-2008, 10:00 PM
There is no quick fix to keep legs from hyperextending, unfortunately.

Balls!!!


Anyways about the eyebrows, ill give that a go, that should be cool. And brainnoise, I'll see how it looks shifting the weight a bit more, I was a bit tentative because at first I used to go over the top with walk cycles so maybe I over compensated.

And thankyou everybody who has taken the time to watch my animations, think, and feedback. I'm just reinstalling windows because My PC keeps crashing, I think its most likely over heating or under powered (psu wise) but I'm desperately hoping it just needs a format. I'll post some updates as soon as my wretched PC will allow.

One question in the mean time, is it better to block in walk cycles with stepped curves, or spline?

Animatter
07-26-2008, 09:59 PM
Hey! I got my computer fixed and its running better than ever!

I decided to start from scratch so I could keep track of everything.

Here it is with just the legs animated so it would be easier to focus on the problem I always seem to have with the knees

http://www.angelfire.com/mattjmit/knees.html

This is the most common problem I have and any other issue I had with the knees on the previous walk cycle was just a result of me desperately trying to rectify it.

Please tell me where I should go from here as I'm having real trouble identifying the route of the problem.

Thanks.
Matt.

Nucleo
07-27-2008, 06:14 AM
Hey man,

There is no easy solution to fix the knees or just a single part that creates this problem as far as i know. The best thing you can do is study walk cycles as much as you can and try to get the hips and feet to work and then you will have smaller knees pops. Then you can go in there frame by frame and fix them.

A few tips i know that could help are :

- try have the knees move forward (Depends on the walk style too)
- a walk is a controlled fall constantly falling and catching yourself. You dont show that in your last playblast which is another reason to :
- Fix everything first and leave the knees for last.
- stay true to anatomy
-Try experimenting with the up and down movement of the body. Make it more subtle.
-S&S(on the legs) can be your friend when trying to fix knee pops.

Well these are my thoughts. I hope this help.

Andreas

Animatter
07-27-2008, 10:59 AM
OK I'll et going on that.
Whats S&S though??

oh also, do people ever use fk on the legs to controll the knees better? the problem seems to be that with ik any small movement at either end of the leg is magnified on the knee. I'm ok with walkcycles in theory, I can do a hand drawn one with no knee popping, (although the curves may not be super smooth) but when it comes to 3D where you dont directly touch the knee, the knee goes crazy. Thanks for those other pointers though. I have had a problem with the knee moving backwards on this one. in betwen the highest position and the contact.

Nucleo
07-27-2008, 02:52 PM
S&S = squash and stretch just a quick way of typing (Make it subtle though as it can ruin your animation). I dont think there are rigs with FK on legs it would be much more harder than fixing the knees but iam not sure.

Depending on the rig you might want to enable knee pivot or knee IK where you can control it directly and extend the lenght of the leg.

mattjmit
07-27-2008, 05:59 PM
Cool, im going to spend some time putting all this to practice then, thanks for your help.

switchblade327
07-29-2008, 12:40 AM
OK I'll et going on that.
Whats S&S though??

oh also, do people ever use fk on the legs to controll the knees better? the problem seems to be that with ik any small movement at either end of the leg is magnified on the knee. I'm ok with walkcycles in theory, I can do a hand drawn one with no knee popping, (although the curves may not be super smooth) but when it comes to 3D where you dont directly touch the knee, the knee goes crazy. Thanks for those other pointers though. I have had a problem with the knee moving backwards on this one. in betwen the highest position and the contact.
S&S = squash and stretch just a quick way of typing (Make it subtle though as it can ruin your animation). I dont think there are rigs with FK on legs it would be much more harder than fixing the knees but iam not sure.


Yeah, I haven't seen many rigs with stretchy bones on the legs (assuming that's what you mean). Actually, I haven't seen any but maybe some of your fancy AM rigs have it :P

On a 3d Studio Max biped rig it's possible to use FK on the knees because of the way it handles IK/FK switching (entirely seamless) but on most rigs where you have to switch, it would be waaaaay more trouble then it's worth.

In this case, using trajectories can be really helpful to get the knee looking right. Minor adjustments in the height of the body root at the highest point of the walk cycle and the rotation of the hip bones are probably the easiest way to fix the popping but it's a delicate balance to keep the curves smooth and not lose the character of the walk.

CGTalk Moderation
07-29-2008, 12:40 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.