A few weeks ago Jason participated in a workshop called "Spatially Extruded Structures" at the 2016 Robots in Architecture Conference and Workshops in Sydney Australia (link). The workshop was led by faculty from the ETH Zurich and the University of Michigan TCAUP. The official workshop description was:
"This workshop will explore the generation of spatial frame structures extruded in midair. Building upon the Mesh Mould research project developed at the ETH Zurich in close collaboration with Sika Technology AG (Patent Publication No. WO/2015/034438) we will explore the constraints and opportunities that come with non-layer based 3D printing processes This process capitalises on the strengths of industrial robots – precision in space and time – while working strategically with their limited payload by deploying minimal material for maximal geometric definition. The workshop will demonstrate the stages from algorithmic design in rhino python via custom control software to the automated generation of instruction code and the feedback of empirical material behavior back into the generative design code."
There are a number of labs around the world doing research into 3d printing freeform geometries. The most recent notable project are: the Mataerial project (IAAC/Joris Laarman Studio), Branch Technology, the ETH Zurich, Tonji University's Robotic Extrusions project (link 2), and the upcoming MX3D Bridge project, among others.
These projects all combine innovations in design, hardware, software and material science. All of these domains must be integrated and coordinated to work in a highly synchronized fashion. A fascinating diagram from the Robotic Extrusions project (above and below) give some hint of the complexities of coordinating these processes.