At Autodesk's Pier 9 workshop in San Francisco -- and no, this isn't an ad, pull down the description for more! -- there are giant robot arms using welders to 3D print with stainless steel. Which seemed like a good place to talk about programming abstractions, high-level languages, training pendants, and just how safe something like a robot arm needs to be.
FULL DISCLOSURE: Autodesk were good enough to cover my travel to San Francisco, but they haven't paid me and they had no control over the script, the content or the final cut! You can see more about Pier 9 at http://www.autodesk.com/pier-9/ আরও দেখাও