Remote Machining of Prismatic Parts Through the Internet in a CNC Machine Compliant with the STEP-NC Standard
Fábio José Souza1; João Carlos Espíndola Ferreira2; Carlos Alberto Martin2; Wagner Fernando Gascho2
1 REIVAX S/A Automação e Controle; 2 Universidade Federal de Santa Catarina
doi:10.20906/CPS/COB-2015-1632
Resumo
The current standard programming of CNC machine centers is still the ISO 6983, known as G-code, which was developed in the 1950s. This language contains low-level information performing the movement of the tool in the machining process, making it difficult for the operator to take decisions in machining. For this reason, the ISO 6983 standard currently limits significantly the flexibility and interoperability of part manufacturing. Given this scenario, in the 1990s a new data model for manufacturing processes was proposed to extend the ISO 10303 standard (known as STEP), called STEP-NC (ISO 14649-1 standard), which was developed as a result of numerous projects by companies and universities. STEP-NC is based on the concept of workingsteps, machining features and machining operations, among other entities described by the ISO 14649 standard. In this paper we describe the development and validation of software and hardware that allows the user to command a CNC gantry milling machine in order to machine parts using STEP-NC. The STEP-NC controller software was developed using the Java programming language, which enabled the creation of a control interface for the CNC milling machine. A software compliant with the ISO 6983 standard (G-code) generated by the GRBL open source software was used to program the Arduino MEGA2560 microcontroller in the C programming language. G-code programming was removed from GRBL in order for it to be replaced by STEP-NC, allowing the p21 physical file (a part of the STEP standard) to be interpreted and sent to the axes of the CNC milling machine. A direct connection is established between the STEP-NC controller and a board with 8 relays to allow the CNC milling machine to work selectively (either with G-code or STEP-NC). Remote operation of the machine via the Internet was also implemented, allowing the sending of a p21 file through the web, and the machining process can be monitored via webcam.
Palavras-chave: Numerical Control; STEP-NC; Milling Machine; Standardization; G-Code; Internet