One of the foundational aspects of Industry 4.0 protocols is the creation of electronic “digital twin” models of product data and production processes. This includes an exact replica of all machine tools, including complex work envelopes showing the particular spindles, fixtures, and cutting tools. The virtual models correspond with physical shop floor processes and allow manufacturing operations to be simulated, tested, and altered to avoid possible problems and downtime, while also facilitating process optimization. Such cyber-physical systems bridge the gap between the real and virtual manufacturing environment.
The latest generation of advanced machining simulation software works directly with ISO NC machining codes to simulate, verify, and optimize machining programs based on specific parts, tooling, and machine tool characteristics. Three-dimensional graphics help prevent crashes while complex algorithms and embedded process-based knowledge enable optimization of cutting conditions. Use of the software reduces time spent debugging programs, eliminates risk of spindle collision, tool breakage and scrap, and improves cycle times, process efficiencies, and machine OEE (overall equipment effectiveness).
The software provides machining verification in three steps: it investigates and corrects coding errors, simulates to detect collisions and correct motion errors, and validates the machining results. It also monitors production transfers, tool management, and machine status. Its use can help manufacturers meet delivery schedules, maintain product quality, and reduce preparation times up to 70 percent, while cutting costs 20 percent.
When programmers simulate and view the process in a digital twin, they see the acceleration and deceleration of the machines, the macro programming routines, and so on. They have a much closer estimate of how much time it will take to process a job, thereby improving the scheduling on that particular machine or in that specific cell. More accurate scheduling leads to improved deliveries and higher customer satisfaction.
Further, troubleshooting the G-code on the computer is a much smarter and more efficient approach than proving jobs out on machines. This is not exactly news. Manufacturers understand that machines should be working and not playing.
However, what is new is how everything going on in the background of these programs is becoming more accurate, more robust, and truly plays well with most major CAD and CAM programs. Better integration via API leads to better modeling, coding, and communication between the engineering and machining departments.
Of course, even though much of the prove-out work can be accomplished on the computer, an operator may sometimes need to make an adjustment on the actual machine. We call it “automation,” which allows uploading the modification so that it’s applied to the future runs of that particular job as well.
A key benefit of simulation, according to our customers, is the ability to experiment with the digital twin. For example, they can nudge the accel/decel and see what happens. Oftentimes, they discover in the digital realm that it can be pushed a little without problems, and the real cycle time gets shaved by a few minutes. Multiply that by a large lot of parts, repeated several times a year, and that testing becomes very profitable.
An advancement not too far into the future will provide messages during this testing phase, warning that the programmer is going beyond the bounds of the machine, in essence saying “stop wasting your time.”
We feel fortunate to be in the thick of the revolution with a product and capabilities that users need now and certainly even more as Industry 4.0 continues to evolve.