Rigging 4 bones together at a triangle shaped joint

I’ve got a basic lamp going on and i want to rig it completely.

Basically you can see that each part of my model affects each other part of my model.

You can see on the corner there is essentially a solid triangle moving 2 seperate objects. If the top 2 objects move downwards, then it will cause the triangle to rotate anti clockwise, and thus the arm on the bottom left will move downwards.


I think what i’m trying to say is, I want to join these 2 bones at the top. So if i move the bone on the far left, they all move together but still anchored at the very bottom bone.

For example here, if i move the left object up, i want everything to rotate slightly, but then the top 2 objects must stay the same distance apart and not be able to move apart or closer (as they are joined at the top by a triangle joint thing)

How do i ensure 2 bones stay the same distance apart, by their head sections?


Please supply a blend. It will help us help you. IK constraints will likely be the answer for that rig.

Sure it can be found here:

I did try an IK and got it almost working but only for the bottom part. Now im stumped again…

https://drive.google.com/file/d/0Bz4wvYT4vWztOHczOFY1ME0xWDQ/view?usp=sharing

Does anyone have a possible solution?

My next issue is that i’ll need to export it all as an FBX file. Can IK’s be exported into FBX?