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Columbo24
04-07-2014, 12:49 PM
Hello
I've been studying the tutorials RH rigging and the dolphin tutorial for modeling. More questions.(I've been learning lightwave for 6 weeks and no other animation experience except for AE &Motion)
1.Can somebody give me a simplified explanation of IK vs FK.
2.I want to animate a robot spider. One orb with 4 legs coming out of the top of the sphere. Each leg is 3 long cylinders with two pivot pts. for the leg action and a third pivot point where it attaches to the head. Would I use IK or FK?
3.Is there a really simple tutorial to just get my feet wet with IK that I could apply to this animation or is this above my pay grade for now? I need to apply what these tutorials are teaching me , sometimes they're just over my head for now.
4.I was able to build an aquarium with gravel and actually animate a fish swimming with bones.It needs a lot of improvements that will come with time. I key framed the bones moving individually. I have four layers.Fish body and fins,dorsal fin and two eyes. I used the scene editor to parent the eyes and dorsal fin to the torso. I put 4 bones in the fish body. Problem is when I animate the bones separately with keyframes the eyes and fin do not move with the bends in the body. Any suggestions?(I'm still wrapping my head around the spatial,rotational hierarchies etc.) Should I be using IK for this?
Again thanks for everyones help.
Bill

RebelHill
04-07-2014, 01:23 PM
1. this is about as simple as it gets... https://www.youtube.com/watch?v=gd1ds0gKnYU&index=8&list=PLTds3QePYrWEWipwKkLmyNT4Tf_JTigM2
2. feet are in contact with the ground... refer to the video.
3. yep... https://www.youtube.com/watch?v=T2VYPnVIW0Y&list=PLTds3QePYrWEWipwKkLmyNT4Tf_JTigM2&index=16
4. you need to set the extra objects to use the same bones... select object (switch to bones mode, properties, use bones from... Or... just make the object one object/layer... much easier. As for animating the bones, u can use IK, but ideally u want some overlap in the action... so... (back to that first video again).

Ryan Roye
04-07-2014, 05:56 PM
2.I want to animate a robot spider. One orb with 4 legs coming out of the top of the sphere. Each leg is 3 long cylinders with two pivot pts. for the leg action and a third pivot point where it attaches to the head. Would I use IK or FK?

Is the first critter in this video similar to what you're looking for? If so I'd recommend experimenting with IKBooster part time IK; you get the best of both worlds and can apply it to IK rigs if you want.


https://www.youtube.com/watch?v=E6B-bjJ2mHA