View Full Version : I'm trying to animate an elephant's trunk

01-04-2009, 06:33 PM
I've created bones and weight maps. I've tried using IK Booster but I'm not quite sure what I am doing wrong. I tried setting the end bone in the end of the trunk with just a limit on the pitch and it is better but not working right yet? Any suggestions?

I saw the video on the 24 hours free training on introduction to bone dynamics and the octopus has the kind of movement I want as far as the tentacle curling? I could sure use any pointers on how to get that kind of movement for my trunk.

01-05-2009, 03:56 PM
Lock your heading channels.

Also, a quick screenshot would be good to see what is messing up.

01-05-2009, 09:02 PM
I'm still learning to use these forums. So, I did not even know how to put a picture up here. The heading lock didn't work though, and just locking the pitch you can see what is happening....any ideas? Thanks for the help.

01-05-2009, 09:41 PM
For a trunk I wouldn't lock any headings.
There is a bone right below the eyes. Did you click IK STOP on it? If you want a few curls in the trunk, make the bones smaller so you get more control and put in more IK STOP points.

Good Luck

01-05-2009, 10:08 PM
looks like the bank is spinning on one of the bones in the trunk. My guess is don't lock heading, but try locking bank!

01-06-2009, 03:11 PM
Thanks so much, I'll give it a try and let you know.... I did not put an IK stop on the bone between the eye - and I did not put IK stops on any of bones in the trunk
Thanks much....I'm still learning and desperately trying to get this to work.....

01-07-2009, 11:22 AM
I'm not a rigging expert, but attached is a scene and object file that may help you.

The object file contains a fake elephant and trunk along with skelegons.

The scene file has the model loaded and skelegons converted to bones.

I have 1) locked the X,Y,Z of each bone, 2) placed Heading and Pitch limits to limit the trunk movement to some reasonable angle (you can change this in the bone motion properties), 3) locked Bank but you may just want to place some Bank limits as opposed to locking, 4) enabled IK booster, 5) created a Trunk weight map and instructed the bones to use the weight map (just for grins).

When you open the scene, enable IK Booster in the Modify tab.

Grab the end bone and start dragging it around. I don't see any twisting.

Professional riggers out there may want to wave a magic wand over the scene to help you even more.

This scene is for 9.5+ so if you're using 9.3.x and earlier you will need to get the latest.

I hope this helps you.


01-07-2009, 03:17 PM
I just wanted to say Thanks to all of you for your help! i did try to split trunk bones and that has really helped a little more with the control. I've been trying to lock different combinations of locking bank, pitch and heading....
WOW! I really appreciate the files. I will try the files.... You guys are incredibly AWESOME! It has been really hard for me to get this to work...and I still have much to learn....
Thanks So Much!

01-07-2009, 03:37 PM
you could try stop motion style, FK animation. Not so elegant but gives you total controll over your bones.

01-07-2009, 06:35 PM
Beginning of this video shows how you might want to set it up:


Worth watching the others in the series too:


01-10-2009, 11:43 AM
Daniel the files really helped, but the x,y, and z did not show as locked in the settings when I opened them, but those files are really good. Thanks much! You look like you are really good at rigging. Thanks to all of you again for your help, and I will definitely check out the videos. This idea just got bigger and harder than I thought it would be... I didn't realize how hard getting it to deform/react right would be....
Thanks Again!

01-12-2009, 04:14 PM
Also, using precidias generously supplied scene, try this:
In a new scene import the trunk test object
Go to convert skelegons to bones.
Open the scene editor select all the bones and assign the trunk weight map under the bone's influence. ( not absolutely necessary for testing but a nicer effect.)
Back in the main layout window click the bones button at the bottom and select all the bones
press y for rotate and just start moving your cursor around in the window.
If you select all bones in a chain and rotate it can be very effective for things like tails, trunks and other flailing appendages. :)

01-12-2009, 05:48 PM
Artsy7, I am glad the scene helped you.

What I meant by "locked the X,Y,Z" is that the X, Y, and Z channels for each of the trunk bones is locked.

Attached is a screenshot of the scene editor. When you first open the scene, select the "Scene Editor->open..." menu item. I expanded each of the trunk bones.

Notice the red lock for each X,Y,Z for each bone (Channels:Lock States under the Property tab).

If you select any of the bones in the trunk and press the 't' key (Modify->Move menu item) you will not get the z/y/z move direction arrows. That is, you cannot move (translate) the bone.

This is done so you don't accidentally move a bone. The more you can lock down and restrict your rig (restrict bone rotations, etc.) specific to the constraints of your character or object, the easier life will be during animation.


01-12-2009, 06:16 PM
Artsy7, two other tidbits I have learned.

Bone rotation is very important. Start early and check often.

When I create skelegons, I spend time ensuring the bone rotation (pitch) is correct in the skelegon.

Attached is a screenshot of the skelegons in modeler. I have selected the "Edit Skelegons" menu item. Notice the large circles at each bone connection point. More importantly, notice the small circle connected to the large circle by a line. This point shows the bone rotation. In this case I ensured each of the trunk bones are oriented down the trunk with the bank rotation handle vertical and in-line with the trunk.

If you have the bank rotation handles properly configured in Modeler, then when you bring them into Layout and convert them to bones, all the bones will have the proper pitch alignment.

The second screenshot I have attached shows the green pitch circle all properly aligned vertically down the length of the trunk in a nice even plane.

If you don't align the bone pitch properly your bones will bend and twist in all sorts of weird ways when you apply IK to them (depending on how pitch changes from bone to bone).

In summary, it is very important to spend time ensuring that skelegons are properly aligned (if you use skelegons, some people don't, but I like to keep my initial bone structure embedded within the model) and that the bones are all rotated and aligned properly before you apply IK and start moving them.

Combine that with locking down X,Y,Z and rotation angles and you will create a very solid rig that won't have a crazy hair day when you apply IK/IKBooster and start moving them.

Rigidity breeds stability. Or is that the other way around?