Rigging a robotic arm I made a model and an armature, which I did not parented yet to the mesh. I want the robot rotate towards a specific bone. Through IK I can move the whole armature towards this bone but I want the robot only to be able to rotate on the z axis. So when I move this controller bone, the robot armature should rotate towards this position on the z-axis. Is this possible in blender?
Yes it is.
In every IK chain you can select a bone and set some constraints in the IK tab of the bone section of the properties panel. The XYZ constraints are referred to the bone axis, not to the global orientation.