Getting IK Handles to Work

As mentioned in the last part, I wanted to seek some advice about my IK handle problem, I do so by speaking to one of my lecturers who suggested creating a pole vector constraint using control curves that were parent constraint to the joints. This system would mean that the direction the pole vector was would be the direction the knee would face.

Obviously this worked, it meant that I wouldn’t need to move any joints around, which would save me some time and it would ensure that the knee joint would always move in the correct way no matter how I rotated the IK handle.

However, when adding the pole vector constraint, it twisted my mesh. Unsure for the reason this happening I looked online and found a forum post where a user called SuperSparkplug was having similar issue. I was lucky enough to find the solution to my problem in the replies to SuperSparkplug’s post:

“…i would do the skinning after rigging, since the joint chain normally twists a bit, after adding an IK…” (antweiler, 2015)

Simply by unbinding the joints from the mesh and then binding them again fixed the issue.

Now better understanding how IK’s work, I decided to also add them to the arms of my bear, this way I’ll be able to animate my model, for example, grabbing a chair and walking around it keeping it’s hand in the same place.

As I mentioned earlier, for this rigging with the IK handles, I used curves that control the joints. This means that I can freeze the transformations of these curves without worrying that the mesh will deform. An added benefit to this is that I will be able to zero any of the control curves after transforming them when animating and have my model go to its original pose. So that I will be able to do this for all the joints, next time I’m going to add in control curves for all them.

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Bibliography

SuperSparkplug (2015). [Maya] IK Handle deforming model. [Forum Post] Polycount Forum. Available at: https://polycount.com/discussion/147898/maya-ik-handle-deforming-model [Accessed 5 Dec. 2019].

antweiler (2015). [Maya] IK Handle deforming model. [Forum Post Reply] Polycount Forum. Available at: https://polycount.com/discussion/147898/maya-ik-handle-deforming-model [Accessed 5 Dec. 2019].