FullControl GCode Designer: Open-source software for unconstrained design in additive manufacturing

A new concept is presented for the design of additive manufacturing procedures, which is implemented in open-source software called FullControl GCode Designer. In this new design approach, the user defines every segment of the print-path along with all printing parameters, which may be related to geometric and non-geometric factors, at all points along the print-path. Machine control code (GCode) is directly generated by the software, without the need for any programming skills and without using computer-aided design (CAD), STL-files or slicing software. Excel is used as the front end for the software, which is written in Visual Basic. Case studies are used to demonstrate the broad range of structures that can be designed using the software, including: precisely controlled specimens for printer calibration, parametric specimens for hardware characterisation utilising hundreds of unique parameter combinations, novel mathematically defined lattice structures, and previously inconceivable 3D geometries that are impossible for traditional slicing software to achieve. The FullControl design approach enables unconstrained freedom to create nonplanar 3D print-paths and break free from traditional restrictions of layerwise print-path planning. It also allows nozzle movements to be carefully designed - both during extrusion and while travelling between disconnected extrusion volumes - to overcome inherent limitations of the printing process or to improve capabilities for challenging materials. An industrial case study shows how explicit print-path design improved printer reliability, production time, and print quality for a production run of over 1000 parts. FullControl GCode Designer offers a general framework for unconstrained design and is not limited to a particular type of structure or hardware; transferability to lasers and other manufacturing processes is discussed. Parametric design files use a few bytes or kilobytes of data to describe all details that are sent to the printer, which greatly improves shareability by eliminating any risk of errors being introduced during STL file conversion or due to different users having inconsistent slicer settings. Adjustable parameters allow GCode for revised designs to be produced instantly, instead of the laborious traditional routine using multiple software packages and file conversions. The FullControl design concept offers new opportunities for creative and high-precision use of additive manufacturing systems. It facilitates design for additive manufacturing (DfAM) at the smallest possible scale based on the fundamental nature of the process (i.e. assembly of individual extrusions). The software and source code are provided as supplementary data and ongoing updates to improve functionality and the user interface will be available at www.fullcontrolgcode.com.