PDA

View Full Version : end effector won't move


marvelatthedust
04-10-2007, 11:24 PM
i've been following few tutorials around, and i've gotten stuck, and wanted to cry for help here:

HELP!

i'm trying to rig an arm with 4 joints (shoulder, elbow, forearm, wrist) and the tute tells me to connect eh ik handle from the shoulder to the forearm, then move the effector to the wrist, the only problem is that everytime i try to move the effector it throws all the rotations off from the ik handle, and the joints end up in limbo, or somewhere nearby. is there something i am missing? some step i skipped over, or is in an id10t error?
please let me know!


thanks!

marvel

_stev_
04-11-2007, 12:11 AM
If you're using maya, to move the effector you have to hit the "insert" key, then move it to the appropriate joint, and hit "insert" again.Stev

Darksuit
04-11-2007, 12:13 AM
Lets say your using Maya Hypothetically (much better than assuming your using Maya)

After I create the joints in maya (I will start with all the joints in a straight line. Then selecting the Elbow Joint I will rotate the joint say 15 to 45 degrees in the direction i want it to bend, then right click on the joint and tell it to "set perfered angle". This will help to make sure that my arm bends correctly.

In Maya you have 2 types of IK (SC and RP). SC stands for Single Chain and RP stands for Rotate Plane. When I set up an arm in Maya, I will use the RP solver. So when I am selected in the tool, I will open up the tool options window to double check that I am in RP solver mode for creation.

Selecting the Shoulder then the ForeArm, the Forearm being the end of the chain. To Move the effector, I will then open the Outliner and select the Effector, making sure I am in the Move tool ("w" on the keyboard) I will click the "Insert" Key if I am on a PC "Home" if I am on a Mac. This allows me to adjust the pivot location for the Effector.

Holding downt he "v" key I will move the Effector to the Wrist. Holding down the "v" Key allows me to snap the selection riht to a joint.

At this point you can add in the Pole Vector Control and any other controls.

Homefully this will help you out. =)

marvelatthedust
04-11-2007, 12:50 AM
thanks darksuit,

i've followed all of those steps again, (just loaded up maya again to see if the preferred angle makes a difference) and it still throws the rotations off on the joints.

this has been my process (in maya 7):
(from http://www.thegnomonworkshop.com/tutorials/arm_ik_fk.html)
place 5 joints, make sure rotations are good on the forearm. place an ikhndle from clavical to shoulder. place ikhndle from shoulder to forearm. select the effector in the outliner, hit 'w' in the main screen hit 'insert', hit 'v', grab the handle the slide towards the wrist joint. the effector will spasm, then snap back to its original position, but the arm joints end up (usually) rotated behind the back or through the torso. i can't tell if there is some setting that i've screwed with, or if it's a glitch, or some gremlin in my pc... or the entirely possible user error :P
anyway, if anyone has ny ideas, i'm more than happy to try 'em...

thanks again!

marvel

Darksuit
04-11-2007, 03:50 AM
post your maya file, that way i can see exactly what is going on and let you know how to fix it.

marvelatthedust
04-11-2007, 12:54 PM
heres a link to the file:
http://www.ubasics.com/iannovation/images/bonesRedo1.ma

thanks for your help!

-marvel

marvelatthedust
04-11-2007, 01:10 PM
heres a link to the file:
http://www.ubasics.com/iannovation/images/bonesRedo1.ma

thanks for your help!

-marvel

Darksuit
04-13-2007, 08:34 PM
Sorry for taking so long to get back to you. Been a little busy here.

So I took the file opened it up. The first thing I did was parent the Shoulder/Arm into the spine. Then applied a IK RP solver from the base of the shoulder to the forearm joint. Then I opened the outliner and held down shift while selecting the Plus Symbol next to the root joint. (This fully expands the heirarchy in the outliner) Then I changed to the move tool and selected the effector within the outliner. With this done I was able to click "Insert" on the keyboard to move the effector holding down the "v" key allowed me to snap it out to the wrist joint. Clicking on the "Insert" key again to take me out of move pivot mode.

Doing this I had no issues with your file.

=)

So its all there, just a matter of learning the steps, and doing it a couple times.

marvelatthedust
04-14-2007, 06:57 PM
ahHA!, i found out what i was doing wrong. thanks so much for your help darksuit.
the big problem was with my ikHandle settings. i had the 'sticky' toggle on, which is what caused the effector to move the bone when it moved, i guess...

so is there any reason to have sticky on in the future? that's the way i was taught to set ikhandles up before, but i'm pretty new to this, so there is almost certainly a better way...

thanks again for the help!

-marvel

CGTalk Moderation
04-14-2007, 06:57 PM
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.