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View Full Version : IK Flipping/Twitching Problems



Nicolas Jordan
04-30-2007, 12:18 PM
I am trying to animate a Oil Pump and I can't seem to solve this IK Flipping problem. I have had this same problem in the past on things like bone chains for tails but inserting a secondary goal midway with a different goal strength usually solves it. I also tried to prebend the model at the joints so they aren't at 90 degree angles but that doesn't seem to work either. I attached the scene and object file with a 100 frame animation of it the pump cycle. Any help with this is much appreciated.

adamredwoods
04-30-2007, 12:27 PM
One trick I've learned lately is that you can help the IK solver by setting the stiffness under the motion->limits panel. set 0 for your main movement on one of the HPB axis (say Pitch), then set a range of 10-20 for the secondary axis (say H) and then double the last value for the last axis (say Bank).

I've noticed this helps IK solve for each of the axis's in order.

I haven't looked at your file, so I can't say which order or if this will solve it outright. I do know there are many ways to solve this problem (IKBoost, Spline control displacement modifier, etc.)

Nicolas Jordan
04-30-2007, 12:41 PM
That worked really well! Theres no more IK flipping now. Your help is very appreciated, thanks a lot. :)

SplineGod
04-30-2007, 02:40 PM
Usually the simplest way is best. :)
Try this too...
http://www.3dtrainingonline.com/examples/dog_leash.mov