Abstract:
Development of Smart Factories (SF) renders an incredible opportunity for
the manufacturing industry to join the fourth industrial revolution (Industry 4.0).
With use of Digital Twin (DT), Edge Computing (EC), Machine Learning (ML)
concepts and being part of a whole as interconnected Internet of Things (IoT) SF
can collect and analyse data from sensors and embedded software for better
decision making, real-time visibility of manufacturing assets and predictive
maintenance in order to minimize machinery downtime.
Many manufacturing plants still operate conventional machines with a
Computer Numerical Control (CNC) which blindly execute given programmed
instructions. Such machines usually can be connected to a network only for
uploading these instructions and some machine parameters into the machine.
The instructions or programs consist of G-code and M-code sequences and
must be generated for every machine model and for each processed
component individually prior to manufacturing.
As part of the move towards SF it is vital to use a control language with the
ability to carry more product related data compared to G-code and M-code
language. Standard for the Exchange of Product data compliant Numerical
Control (STEP-NC) addresses these concerns. STEP-NC links process data to a
product description of the manufactured component.
During these transitional times then not every piece of equipment supports
features of the SF especially conventional CNC machines which are widespread
and still in use, but the lack of the cyber features prevents them from being
integrated into a SF. It is becoming more vivid to find ways to convert a
conventional CNC machine into a Cyber-Physical Machine Tool (CPMT)
compatible with requirements of Industry 4.0.
With current achievements of the open-source community, level of network
technologies and availability of electronics, minimal investments required to
transform a conventional CNC machine into CPMT with a highly configurable
system tailored to needs of a SF.
Developed framework provides network integration for a CNC machine and
uses a bypass of conventional CNC controller’s workflow to establish a Smart
Numerical Control (SNC). SNC is a dispersed network system that can control
more than one CNC machine and modify toolpath being executed in near realtime
manner for closed loop manufacturing with no need for G-code. The SNC
provides sensors data management and an interface to control these CNC
machines with other software, for example by obtaining a toolpath from a
STEP-NC file.