Infrastructure project developed and funded by University of Nottingham’s Strategic Development Fund.
The FA3D platform is the testbed where newly developed innovative and ground breaking assembly methods and solutions for cost-effective future aerospace manufacture are tested and validated.
Manufacturing systems are often characterised by ‘silos’ of data which cannot be accessed easily horizontally, and by varied and incompatible data types. By utilising a single data bus for all data to be transmitted on, standards are more easily implemented and all data is accessible by all equipment.
This is particularly important in this context where diverse sources of data (such as metrology systems, CAD data) must be analysed by software (e.g. data analytics, metrology software), and then used to adapt a process (e.g. robotic pathing, machining processes).
When a manufacturing system is fixed and will repeat the same tasks, having hard-coded and non-dynamic data exchange may be sufficient. When a system is reconfigurable and flexible, being able to define data sources and destination in software is critical (so-called software-defined networking).
Integration of adaptive robot control technology into a complex and variable manufacturing process allows for accurate positioning of assembly components despite variability in component manufacture, existing assembly deviation, and the robots themselves.
This allows for progress towards jig-less assembly – saving non-recurring costs in the assembly of large, low batch products. Rather than building large, welded jigs and fixtures, robots are used to position and align parts. As the robots can easily be reused, this saves significant time and money.
Note: Since this demonstrator implementation, the Adaptive Robot Control and K-CMM technologies are now available from True Position Robotics .
SMEs often have an advantage over larger companies by being agile and able to change to meet demands more easily. However, this is only possible with an agile and flexible data system. For many SMEs, this burden is carried by human workers, with manual and often paper-based data management and exchange systems.
By implementing a common manufacturing service bus for data, this reliance on human data input (and the associated risk of error and time burden for skilled engineers) can be reduced, and data standards can be more easily implemented.
Though the integration of adaptive robot control represents a significant upfront cost, the ability to save money on fixturing in the long term makes the creation of low batches of large, accurate products a more realistic proposition for small to medium enterprises.
As the robots can be re-used over and over for different situations, it enables significant flexibility in what products and product variants can be built.
For flexible, reconfigurable systems where everything is connected together and must utilise a common data format, selecting the correct data format and a common structure for its use is key. B2MML worked very well for this application, but there is still scope for variation in the way terms and variables are defined, which must be settled on.
Converting an agreed process plan for manufacturing into the B2MML has some degree of automation, but also required a large amount of manual processing. More time should have been spent on automating this process.
Ideally, all components of the system would communicate directly with the service bus. Practically, not all devices will support the service bus, so use of an intermediary communication protocol such as OPC UA may be necessary.
Although process control may all be centralised with a manufacturing service bus, safety systems may not be. This can cause unexpected system behaviour when the system starts a new process unless the safety system is fully understood by the users.
Selection of flexible technologies and standards does not necessarily mean that any given implementation using those technologies will be flexible. A system implementation must be designed specifically to be flexible and future proof.
The ARC robotic control system is extremely effective for bringing a robot / part to a specific and highly accurate location. However, it does not allow for accuracy along a path, so would not be appropriate for continuous path accuracy e.g. robotic milling or welding.
The large amount of metal in the cell (robots, parts) dramatically lowered the accuracy that was possible with the RFID positioning system. Rather than being able to track parts to a specific location, we could determine no better than if a part was inside or outside the cell. Active RFID tags may help mitigate this.
K-CMM technology was extremely effective, but subject to line-of-sight restrictions for large assemblies such as aerospace fuselages.
When integrating technologies and solutions from multiple equipment vendors, the challenge is almost always interoperability and standards compliance. The ARC system was comparatively simple to integrate and commission, but integration into the larger context of a manufacturing process with a SCADA and other physical devices was more of a challenge.
OPC UA (Kepware) – Many devices could not interface directly with the service bus, so OPC UA was used to extract data and publish it to the service bus.
B2MML – Business to Manufacturing Mark-up Language. Data standard used to define the process (i.e. the set of operations to be carried out by the cell for each unique product), what resources are required for each process, the materials needed and more. The full process would be designed by engineers, and then the SCADA would break the ‘master’ B2MML process representation into sub-processes and send these to the resources via the service bus. These would then trigger the start of processes by the PLCs.
B2MML – Business to Manufacturing Mark-up Language. Data standard used to define the process (i.e. the set of operations to be carried out by the cell for each unique product), what resources are required for each process, the materials needed and more. The full process would be designed by engineers, and then the SCADA would break the ‘master’ B2MML process representation into sub-processes and send these to the resources via the service bus. These would then trigger the start of processes by the PLCs.
ATS Bus - Enabled a single, common service bus for data exchange between the PLCs and other high level components of the system, including a SCADA system. Used a broker-based publish-subscribe approach to decouple the physical sources and destinations of the data to facilitate reconfigurability.
RFID Positioning System – Use of multiple RFID receivers within the cell would allow for 3D location tracking of the parts to be assembled in the system, ensuring parts are correctly present and in the right locations before proceeding.
User interfaces were designed in WinCC
Nikon K-CMM Metrology - By positioning LEDs on the robot end effector, and on the target parts, the K-CMM system can measure relative positioning to a very high degree of accuracy even over large distances.
Siemens TIA Portal, WinCC, PLCs – The lower level control of resources in the system was performed with Siemens brand programmable logic controllers
Nikon Adaptive Robotic Control (ARC) – this technology allows data from metrology systems to correct a robot controller’s coordinate system and compensate for inaccuracies and variability.
KUKA Robotics – Compatible with the ARC system, the KUKA robots were used for part positioning.
Siemens Totally Integrated Automation Portal (TIA Portal)
OPC UA (Kepware) – Many devices could not interface directly with the service bus, so OPC UA was used to extract data and publish it to the service bus.
ATS Bus - Enabled a single, common service bus for data exchange between the PLCs and other high level components of the system, including a SCADA system. Used a broker-based publish-subscribe approach to decouple the physical sources and destinations of the data to facilitate reconfigurability.
Nservicebus - The underlying technology which enabled the ATS Bus to exchange data.
OPC UA (Kepware) – Many devices could not interface directly with the service bus, so OPC UA was used to extract data and publish it to the service bus.
OPC UA (Kepware) – Many devices could not interface directly with the service bus, so OPC UA was used to extract data and publish it to the service bus.
B2MML – Business to Manufacturing Mark-up Language. Data standard used to define the process (i.e. the set of operations to be carried out by the cell for each unique product), what resources are required for each process, the materials needed and more. The full process would be designed by engineers, and then the SCADA would break the ‘master’ B2MML process representation into sub-processes and send these to the resources via the service bus. These would then trigger the start of processes by the PLCs.
B2MML – Business to Manufacturing Mark-up Language. Data standard used to define the process (i.e. the set of operations to be carried out by the cell for each unique product), what resources are required for each process, the materials needed and more. The full process would be designed by engineers, and then the SCADA would break the ‘master’ B2MML process representation into sub-processes and send these to the resources via the service bus. These would then trigger the start of processes by the PLCs.
