The National Institute of Standards and Technology (NIST) has rounded up manufacturing and software companies to participate in a project that will demonstrate the advantages of replacing 2D computer-aided design (CAD) drawings with 3D virtual models. The project will outline the benefits of using standardized 3D models in a “digital thread,” from initial design to inspection of the final part. The “digital thread” is the manufacturer’s term for the electronic processing and exchange of a part in a seamless string of activities before finalization. The project will demonstrate the compatibility of a standardized 3D part with software and readability for all designers, engineers, and manufacturers involved in the design process.
Starting the digital thread with a virtual 3D model eradicates the need for manual conversion from a 2D virtual model to a 3D model and reduces the risk of errors, redundant effort, and cycle time, the project leaders said. 3D imaging software also allows designers to embed product and manufacturing requirements that are preserved even as a user makes changes to the part. These may include specifications for materials, geometrical and dimensional tolerances, and surface texture. The International Organization for Standardization (ISO) has established STEP AP 242 as the standard of language, format, and protocols for 3D parts with specifications. This standardization allows manufacturing specs to be translated from software to software as the part cycles through the digital thread. Designers also can include process notes and finish requirements in their 3D representations.
The Design to Manufacturing and Inspection Project begins with a 3D virtual part with manufacturing specifications created by Rockwell Collins using proprietary CAD software. The original model is then translated into the standard format defined by STEP AP 242. The standardized part is then sent to Geater Machining and Manufacturing to be translated into the language readable by their CAD software to generate machining instructions. Geater will then test the STEP AP 242 model by using it to generate a code to direct a coordinate measuring machine and determine whether the part is manufactured as designed. All collaborators will document and record their involvement and experiences in the NIST project.
Collaborators in the NIST Design to Manufacturing and Inspection Project include International TechneGroup Incorporated (ITI), Advanced Collaboration Consulting Resources, Rockwell Collins, Geater Machining and Manufacturing, CNC Software, Mitutoyo America, and CoreTechnologie.