I recently attended a session aimed at raising awareness of Additive Manufacturing during a regional manufacturing conference. Part of the message was have manufacturers understand that Additive Manufacturing is moving far beyond its "Rapid Prototyping" roots and, in the right circumstances, it can be a viable manufacturing process for production. If GE's recent moves in this area (GE Developing Additive Manufacturing parts for LEAP engine) didn't make this clear, then manufacturers are simply not receiving the message. So here is an exciting new (not really new, actually; some of the originating technology goes back at least 25 years!) technology that requires the use of a 3D solid model as an input to the manufacturing process but there are not many tools to aid the designer inside the CAD system and seemingly no standards or training for the designer to rely on to take advantage of what this technology has to offer.
Image from CADspan
Developing Modeling Strategies for Design for Additive Manufacturing
Most conventional manufacturing methods (stamping, casting, forging, molding, extrusion, forming, machining, etc.) can trace their roots to a time before 3D solid modeling became mainstream. These manufacturing methods had no reliance on 3D solid models. The early CAD operators and designers would be expected to use the existing best practices (proper draft, avoiding undercuts, minimum radii, etc.) for a particular manufacturing method when creating the solid geometry for components. Eventually, the CAD systems offered analysis capabilities to check for unfavorable geometry, new workflows and wizards were introduced, and new modeling modes (think sheet-metal mode vs. standard solid modeling) were available. These capabilities enabled a skilled designer to develop components faster and allowed modelers with less awareness of the limitations of particular manufacturing methods to still be productive and minimize "no-build" situations.
With Additive Manufacturing the situation is reversed - the solid model was essential for the additive manufacturing machine to work off of; no 3D model, no 3D part. Any best practices that developed (closed solid volume, manifold geometry, minimum thicknesses, support geometry, considerations for orthotropic material properties, joining techniques, etc.) were a result of working with the technology and may be particular to a certain type of machine (there are many classes of additive manufacturing methods; all based on a layered build). These heuristics continue to evolve in this fast-moving field so it can be difficult to establish standards.
What type of training can be offered to designers and engineers to best take advantage of what additive manufacturing has to offer? Who should do this? Should universities be offering classes in Design for Additive Manufacturing? Should the CAD vendors or their VARS do it? What about the developers of the machines? SME, along with the Milwaukee School of Engineering and America Makes, have defined an Additive Manufacturing Body of Knowledge and offers an Additive Manufacturing Certificate Program.
Before I expect to see specific analysis tools integrated into the mainstream CAD tools, the rest of the community (designers, machine developers, academics, etc.) should take the lead in defining what analysis tools and workflows will best take advantage of the opportunities to design with Additive Manufacturing methods. I do think that there are many opportunities here for tools and techniques to be developed to help designers create not just new parts, but new systems. Techniques like integrated topology optimization may really be key in helping to develop ideal structures for production via additive manufacturing. How can CFD be used to help create new geometries for pumps and valves that can not be created with conventional manufacturing methods?
I'm convinced there is a manufacturing Renaissance underway enabled by Additive Manufacturing methods. The engineers, designers, modelers, and artists will need fresh training and new modeling tools and techniques in order to maximize this opportunity.