NC robots can do more with a digital twin  

Robotics integration and edge computing for existing machines 

The Siemens motor plant in Bad Neustadt has equipped a milling center with CNC-controlled robots and edge computing. The highlight: A digital twin of the robot for commissioning and work preparation – even teach-in of new workpieces is possible in the virtual world. 

Stay up to date

CNC4you newsletter

A robot – just for handling? There's more to it than that!   

The robot takes a blank from a blister pallet, places it on an alignment station, and a camera checks the position. The robot then grips it again – now correctly aligned – and replaces the finished workpiece in the milling center's workspace with the new blank. So much for a typical robot handling task – one that has been seen many times before.

 

"Such a level of automation would not have satisfied us. We wanted automation of the entire process – including changing the clamping devices, deburring as a post-processing operation and 100% in-process quality control for changing workpieces.  We also wanted our CNC programmers to be able to create, adapt and optimize the robot programs themselves," says Torsten Franz, Senior Key Expert for digitalization in metalworking and Head of the innovative robotics project in Bad Neustadt. 

System breaks of classic robotics avoided

"Conventional robot programming and third-party controllers would have changed the process chains of the work preparation, and we would have 'split' the automation of the machine and the robot," says Johannes Schunk, Head of Production Technologies/-Planning/Shopfloor Work Preparation in Bad Neustadt. It was therefore decided to integrate a robot made by Comau via Run MyRobot /Direct Control. This means that all robot actions can be programmed and controlled directly with Sinumerik – with precision and using familiar cycles, and avoiding a detour via a third-party controller.

SINUMERIK Run MyRobot and the digital twin: more flexibility, short project run times  

Generally speaking, the Sinumerik CNC of a milling center can control the robot directly. In our case, the robot was given its own Sinumerik 840D sl so that the interruption to production was kept as short as possible. 

 

A further approach to shortening the project run time was provided by the NX CAD/CAM system. This permits the simulation of machine and robot using digital twins, making it much easier to program complex processes – particularly the synchronization between the robot and the machine tool. Using the CAD models of the workpieces, the Siemens team was even able to teach the AI models for workpiece recognition by camera, with the help of the Edge app "Protect MyMachine /Setup". 

Virtual commissioning using the digital twin allowed the machining center to be taken out of production for a significantly shorter time than is the case with conventional commissioning. "Virtual commissioning not only reduces project risks and runtimes, but also has a direct impact on the return on investment of the overall project, especially for brown-field projects," explains Jakob Brottrager from Heitec. Heitec was the team partner for the automated changeover. "Without a digital twin, the project could not have been implemented in such a short time and with such low levels of disruption to production."

Virtual commissioning not only reduces project risks and runtimes, but also has a direct impact on the return on investment of the overall project, especially for brown-field projects!
Jakob Brottrager, Heitec

Familiar programming, familiar process chains: minimum training requirements 

CNC robotics also has other advantages for the Siemens plant: The workforce is already familiar with CNC programming and so can modify and optimize the programming without outside help or additional training. The robot can be programmed in the usual way using cycles, with safety features being integrated directly. Avoiding any breaks in the tool and process chains in the plant. 

In-process quality control and monitoring

The robot and machine tool are each connected to the MindSphere Cloud via Sinumerik Edge. The real-time data is evaluated on the edge CPU, without burdening the CNC.

 

This opens up completely new possibilities – for example in quality monitoring. For example, the process data of the machine tool is visualized via the "Analyze MyWorkpiece /Monitor" app. By making a comparison with a target process stored here, relevant deviations can be detected during processing and affected workpieces can be set aside separately by the robot for follow-up inspections or post-processing.

 

The advantage is that 100 percent of all workpieces are inspected – without an additional process step for quality assurance. In MindSphere, apps such as Manage MyMachines also visualize the data transmitted by machines and robots in terms of utilization, output and other key figures – at any time or location, even remote from the production process. In this way, further potential for optimization can be identified and tapped into.

Robot replaces workpieces and clamping systems, stack pallets – and deburrs  

The CNC-controlled robot at the Chiron milling center in Bad Neustadt now does significantly more than a normal handling robot: The Edge app "Protect MyMachine /Setup" uses the camera images to detect which of the current 13 different blanks are in the blister pallet, and launches the corresponding CNC programs for the robots and machine tools.

 

By deburring the preceding workpiece in parallel with the ongoing milling operation, the robot shortens the throughput time of each workpiece. "Robbie" guides the edges to be deburred over two grinding spindles.

 

If the new workpieces require a change of clamping device, the robot retools the machine.

 

If the blister pallet with the unfinished parts is empty or the one with the finished parts is full, then the robot also restacks the pallets. This means that the cell can be in production 24/7, fully automated and without any personnel. Data on quality and key performance indicators (KPI) are permanently recorded via Sinumerik Edge and monitored remotely. 

Benchmark for CNC robotics 

"At the Bad Neustadt plant, we are demonstrating how digitization and automation can increase productivity on the shopfloor, and how our hardware and software can be used to create comprehensive robotics solutions that can immediately be used by our workforce. Loading and unloading, retooling, post-processing, machining, quality control, monitoring – everything is fully automated. Together with partners like Heitec, our teams have implemented a flagship project for CNC robotics here – and further increased the productivity of our plant," says Peter Deml, Head of Factory, summing up the successful robotics project in Bad Neustadt. "I can only encourage manufacturers and CNC specialists to visit our Arena of Digitalization here at the Bad Neustadt plant, and see what really works in automation and digitalization. What's more: you're talking here to experienced practitioners who face challenges similar to your own."

Visit our Arena of Digitalization here at the Bad Neustadt plant, and see what really works in automation and digitalization. You're talking here to experienced practitioners who face challenges similar to your own.
Peter Deml, plant manager at Siemens' Bad Neustadt engine plant

Feedback on this article

Do you have any questions or a suggested topic ?

Write us!

Related Content