View Full Version : Walk Cycle - Motion Mixer? - Cyclist? = Headache

01-05-2007, 06:37 PM
I am admittedly new to LightWave, but I have played around with other animation software so I think I understand some of the most basic concepts involved. I've also read quite a few of the tutorials I've found at NewTek and elsewhere.

My problem is I can't get my walk cycle test figure to walk more than one step. I've been struggling with this for 2 days now and I think its time to ask for help. I first made a key framed walk cycle where the figure torso basicly remains in place throughout the walk cycle and the limbs move forward and backward. I've tweaked it and tweaked it so the stride moves consistently and the feet stay n the ground plane when I move along the time line. Its not perfect but visually it works.

Once that was done I tried everything making the motion in Motion Mixer. Set Behavior set to Offset Repeat. Tried Baking the Motion. But ultimately everything is giving me the same results. The figure walks in place for one cycle and the stops as the timeline keeps moving. I tried working with Cyclist too, same result.

So I decided that I would make my figure actually move in layout the along the Z Axis length of one stride. When he takes a stride the whole body and limbs move along the Z Axis one stride. I went back into Motion Mixer and my results are just about the same except after making the motion the figure would take one step and then stop as the timeline continued to move, OR the figure would take one step forward and then snap back to the point of origin, take another step, snap back to the starting place, etc, etc.

What am I missing? I know this is operator error once again but I can't seem to find that magic combination to make it walk. I'd be happy with just going in a straight line past the camera for starts. What magic key do I need to press, or what key did I hit that I should have left alone?

Is there a magic tutorial that goes through all the steps of what to do somewhere? Nothing I've read or watched seems to go through everything in a direct line from start to finish.

I have got such a Headache after 2 days of this.



01-05-2007, 07:34 PM
I think its easier to do this in the graph editor.
Get the character to walk forward for one cycle. This should be easy to do after measuring its stride length etc.

Put every channel of every item that youve used to create the walk cycle into the channel bin. whether its IKGoals, bones etc.
you can filter out the scale channels or others you dont need. I also usually create a favorite set so I can pull up the same channels when I need to.

For bones you typically are only concerned with rotational channnels. IKGoals you usually need both translation and rotational channels (if using match goal orientation). You may need the translation channel of whatever item youre using to move the character forward. That can be the character itself, a bone or a null object.

Once you have all the proper channels in the channel bin multiselect them and set the post behavior to REPEAT.
For the item used to move the character forward set that channels post behavior to OFFSET REPEAT. At this point the character should be able to keep walking foward while repeating the walk cycle.

Once youve accomplished that, multiselect all your channels again and hit the b key to BAKE the motions onto all your proper channels This will also remove the post behavior. Now you can filter the keyframes down to something manageable. Doing this will allow you to edit the welkcycle anywhere along its animation and give it a bit more character.
Hope this helps :)

01-06-2007, 07:51 AM
Thanks you so much! I was finally able to a get repeated forward motion cycle of the figure along the Z Axis. I still encountered a few quirks in doing so and it maybe because I didn't bake the channels as you said to. It took a few tries to get something I could work with.

In one instance the figure walked perfectly along Z and part way through the motion dropped straight down along Y from one step to another, but continued to move along Z. I tinkered with things in the channels to see if I could get rid of that Y movement but I just made things worse.

In another attempt the figure walked forward along Z for 40 frames and then slipped/skipped back and the forward along Z several feet, and then resumed action as if nothing was wrong.

I have an idea, but I'm not positive exactly what I did wrong in either instance, but after that slippage in the second description the figure carried along perfectly fine for several hundred frames so I got some useable renderings. At least I hope I got some reasonable renderings. I set up a short walk scene early this morning and its still cranking away as I type. :)

I appreciate your help. I'll have to try baking the channels to see what difference that makes in the movement.


01-06-2007, 08:19 AM
An easy way to tell whats going on is to check out the curves in the graph editor. If your forward motion is nice and linear you should have a nice diagonal line. Any problems will show up as spikes in the graph.

01-08-2007, 08:39 AM
An easy way to tell whats going on is to check out the curves in the graph editor. If your forward motion is nice and linear you should have a nice diagonal line. Any problems will show up as spikes in the graph.

Larry - I went back to the model and corrected a few things, added a few more bones to stop some deformations from happening and then re-did the walk cycle using better animating techniques. Once I had done that I used the channel method you described to get the character to walk without any sudden or erratic movement :thumbsup:

My question is now, when you talk about baking the movement are you referring to baking the single cycle or the longer group of repeated cycles. In this case its 10 cycles repeated. - thanks - Kim

01-08-2007, 12:21 PM
motion mixer can also repeat motion.

assuming you've already added a motion to an actor:
select the motion, right click on it, and select "add post behavior"
right click on the post behavior (which is currently labled "constant")
and select "repeat" or "offset repeat".

that said, I found MM to be very quirky, difficult to deal with and generally a poor tool all around. I wish it was better designed/implemented, because without rock solid tools like MM, we're living in the stone age.

01-08-2007, 08:48 PM
You can bake the single cycle or multiple cycles. Set the post behavior on the relevant channels as I mentioned earlier and you can bake all that. You can also do it in motion mixer and its worked for me as well. I just prefer to be able to have those motion curves right where I can see and use them immediatly to tweak the walk or animation. :)