Ready for production thanks to a digital twin

SINUMERIK ONE controlled gantry-type machining centers: Virtual production start and training on the digital model – full productivity directly after acceptance of the machine
The end customer already received the digital twin for two new SINUMERIK ONE controlled MAKA PM270 gantry-type machining centers while the machines were being built. This means the NC programs including collision test could be loaded and the operator training completed even before the machines were being delivered. As a result, production could start much sooner.
The opportunity to prove the benefit of the "digital twin" for the end user presented itself when MAKA received a request from a leading processor of composite materials and laminates: The customer was open to the suggestion to use the digital twins in addition to the new machines – initially to prepare for production and training, but in the future also for feasibility checks and current tasks in production planning.
Machine owner benefits from virtualization
Alexander Hiller wears many hats at the MAKA Systems GmbH in Nersingen, Germany. He is in charge of electrical engineering, application engineering and the digitalization team. This means he has a pretty good understanding when it comes to the construction and use of machining centers. He is familiar with the topic of "Virtualization" from the perspective of a machine manufacturer as well as that of an end user. This made him a clear proponent of the possibility to use a digital twin as "Software in the loop" controller for digital machine models for CNCs of the SINUMERIK ONE series early on.
Digital twin
Kinematic construction data …
A digital machine twin consists of kinematic construction data, a signal interface and a controller. "This may sound somewhat abstract at first, but we have been working with kinematic construction data for some time now. We use the STL data exported from the CAD system to define for each component whether and which movements the component is capable of in the Cartesian space," explains Alexander Hiller.
… plus Software-in-the-loop CNC
"Until now, we as machine tool manufacturer have mainly used machine models that were created this way ourselves in connection with real CNCs which controlled the machine model as hardware-in-the-loop," says Alexander Hiller. "With SINUMERIK ONE we now have a high-performance CNC that comes with its own digital twin. We can link this digital twin as software-in-the-loop CNC to our machine model to form a complete digital twin that is also useful for the end user!"
The investor or machine operator benefits tremendously from such a "complete" digital twin of the machine including its CNC; a fact that became abundantly clear during the most recent project.
The user receives the "digital twin" long before the machine
The two 9-axis MAKA PM270 gantry-type machining centers that were ordered are standard machines from the MAKA portfolio. In this version, they can process 5 sides and 5 axes of blanks with a cube dimension of up to 7000 x 1300 x 420 mm (with tools up to 160 mm long). After integrating customer-specific options into the design, MAKA created the digital twin of the machine and delivered it to the end customer - many weeks before the actual machine.
Running the actual production completely in advance on the model
Based on the digital twin, the production department could start immediately with the transfer and optimization of the NC programs on the new machines. Because: The CNC is identical to the actual CNC on the machine regarding functionality and operation. Because they are part of the digital machine twin, the virtual preparations made are identical to those that would otherwise have to be made after delivery and acceptance of the actual machine. A digital twin is especially useful for a valid testing for collisions of tools, machine components, clamping devices and the part to be machined. The initial operator training is also conducted on the digital twin.
Increased project safety and drastically shorter production ramp-up
All these measures made it possible that the machines could be used for production immediately after delivery and on-site acceptance. Alexander Hiller summarizes the direct benefits for the end customer: "Compared to deliveries of the same machines to other customers, we know that it usually takes several weeks to ramp up production and train the operators. During this time, the risk of damages to machines that are caused by NC programs that were not sufficiently tested or operator errors is particularly high. During preparation of the production start on the digital twin parallel to the delivery time of the machine, the machine can practically be used for production immediately and the risk of damages is significantly lower. The machine will be making money a lot sooner."
The machine manufacturer also benefits
Even MAKA benefits from this procedure. MAKA can anticipate many of the commissioning steps on a SINUMERIK ONE based digital twin of the machine that have only been possible after the completion of the machine or functional unit in the past. By running these steps parallel to the construction of the machine, MAKA can now reduce the project runtime for such projects by a few days.
Another "major advantage" according to Alexander Hiller: Because a digital twin with software-in-the-loop capability for the CNC SINUMERIK ONE is now available in the company, existing projects can be quickly adapted with less work. "Reloading a hardware-in-the-loop project usually takes many hours. For digital machine twins with software-in-the-loop CNC, the existing project file can be opened directly to make changes."
SINUMERIK ONE and digital twin – the new standard at MAKA
And the additional costs for the digital twin? "The cost benefits when ramping up the machines for the range of parts that the end customer is manufacturing are already much greater than the price of the digital twin. The same is true for many of our existing customers. Furthermore: A single avoided spindle crash including complete productivity loss and repair makes you completely forget the price of the digital twin!", explains Alexander Hiller. "Overall, you will reach Return on Investment much quicker despite the additional investment. Therefore, we will offer our machines with SINUMERIK ONE and the 'digital twin' option as standard in the future."
Project security:
Before the machine is built, it can be clarified based on the digital twin whether the requirements for the ordered machine are complete or if changes to the design or performance data are necessary. The digital twin can be extended from the beginning by the digital models of the clamping devices and equipment that is necessary for the planned production range. Communication with the machine manufacturer will become easier and more specific thanks to the 'live' model.
Shorter production ramp-up
With the digital twin, the NC programs for the production range can be prepared or adapted, verified and optimized while the machine is still being built.
Minimized risk especially during the critival initial phase:
A comprehensive collision check can be performed on the digital twin for each individual NC program; it includes the machine parts, tools, workpieces, clamping devices and equipment. Operator training is also conducted on the digital twin without "trial & error experiments" on the real machine.
Immediate production start, quicker Return on Investment:
Working on the digital twin parallel to building the machine reduces the production ramp-up time by many weeks. Productive operation is often possible immediately after on-site acceptance.
Better machine utilization through significanty improved options in production planning
NC program preparation including runtime optimization and collision check, setup of the machine to a new product using the digital twin parallel to ongoing production minimizes the time until changeover to a new workpiece and increases process security: The machine is more productive, offers can be calculated much faster and more precisely in job order production, and production planning becomes more efficient overall.
… for the machine manufacturer
- Easier, more meaningful feasibility checks
- Improved bid security
- Improved visualization of the machine function (e.g., based on the virtual production of specific workpieces of the potential customer)
- More efficient communication between end customer and machine manufacturer
- Reduced risks during commissioning,
- Shorter project runtimes, e.g. through virtual commissioning. Processes that had to be processed sequentially so far are now run in parallel and overlapping, machines are completed earlier.
- Starting point for new services and business models
At the machine manufacturer:
Tools used at the machine manufacturer MAKA Systems in combination with the digital twin:
- Virtual CAD /CREO: CAD construction, STL data export
- Machine Builder, free tool for turning kinematic STL data into a controllable machine model
- Create MyVirtual Machine: Integration of the machine model with the digital twin of the CNC SINUMERIK ONE (Software in the loop)
- Run MyVirtual Machine: Stand-alone version of the digital twin of the SINUMERIK ONE-controlled machine, can be used without development tools