CAD-BASED AUTOMATED G-CODE GENERATION FOR DRILLING OPERATIONS

Abstract

The automated generation of G-code for machining processes is a valuable tool at the hands of every engineer and machinist. Nowadays, many software systems exist that provide automated functions related to G-code generation. Most free software require the import of a Drawing Exchange Format (DXF) file and cannot work directly on a 3D part. On the contrast, the equivalent commercially-available software systems are feature-rich and can provide a variety of automated processes, but are usually highly priced. The presented application aims to supplement the existing free Computer Aided Manufacturing (CAM) systems by providing a way of generating G-code for drilling operations, using already owned commercial 3D Computer Aided Design (CAD) systems such as SolidWorksTM. Thus, in the case of 3D part drilling, a standard 3D CAD system is sufficient since the code can be adopted by most modern CAD software with minor changes. Moreover, no specialized CAM software is required. In order to achieve this automation, the Application Programming Interface (API) of SolidWorks™ 2018 was utilized, which allows for the design of visualized User Interfaces (UI) and the development of code under the Visual Basic for Applications (VBA™) programming language. The available API methods are employed to recognize the features that were used to design the part, as well as extract the geometric parameters of each of these features. In addition, an embedded calculator automatically defines the cutting conditions (cutting speed, feed and tool) based on the user selections. Finally, the application generates the Computer Numerical Control (CNC) code for the summary of the discovered holes according to the standardized G-code commands; the output can be a typical TXT or NC file that can be easily converted to the preference of the user if necessary.