Robotic arm rig problems

I would like some help with a project. I am making a robot and I need the base to stay still when I move the tip of the arm and I need the end of the arm to hold still when I move the base, and I need a bone to move everything at once. I also need the the arm bones to rotate on one axis relative to the base, I tried accomplishing that with the limit rotation constraint, but failed.

Here is the file, http://www.pasteall.org/blend/33438

It is hard to see whats going on with your model. There are lots of joints! Also there is two duplicate rig on top of each other. I assume you want Armature.001 to work right?

When you say “base” that is the top bone named “bone” right? And the tip, that is bone 006? In that case you need IK target off bone 006. So that when the whole thing can point to it.But then there are too many joints in between and every thing is going to go all over the place. You need to think through exactly how joints should move around.

If you don’t parent the IK target to base bone, IK target will stay put in space when you move the base bone. The tip bone will stay put but pointed to IK bone when you move the base bone.

Oops, I didn’t realize they’re were 2 armatures, they’re both the same I think. The base of the robot is the top . How do I keep the bones from bending sideways relative to the base?

If you want to lock axis all you do is to go to Pose mode, display Property side bar (hot key N), there are Rotation axis and values table there at the top. Each value has lock on it. Select it to lock that axis.

Remember that bones translate and rotate on its own local axis. You can check how axis is pointed by Displaying Axis in Pose mode under Armature button. The check box is next to X-Ray display. Or,just slide one of the axis value to see how bone rotate. After check is made, axis can be locked.

I tried that and it does not seem to effect the bones rotation, it still rotates around every axis.

It seems that when I lock the rotation in the transformation locks section under the bone tab, it does not effect the bone. What I am trying to achieve is a part of the leg that always point up and down, I have not been able to do that so far. Is it possible?

Here is how I resolved my problem, http://www.pasteall.org/blend/33547