Virtual reality technology is advancing. There are many glasses with augmented / virtual reality interfaces. here is demonstration of Meta glasses that enables user to sculpt 3d model with hand gestures and then control 3d printer via virtual interface.
This is how Elon Musk is doing it:
http://diy3dprinting.blogspot.com/2013/09/elon-musk-is-iron-man.html
Company page:
https://www.spaceglasses.com/
ZeroUI 3d sculpting software:
http://www.zeroui.com/
Update (26.5.2014.):
Here is another similar project but with less interaction based on CastAR optics:
http://diy3dprinting.blogspot.com/2014/05/virtual-reality-interface-for-3d.html
