The machine crashes during testing. No problem if it is just virtual commissioning. The significant benefits of model-based engineering and simulation with hardware-in-the-loop are demonstrated by the international packaging manufacturer WestRock.
In mechanical engineering, the design process traditionally begins with the mechanical design. After this, a strict sequence is followed: The mechanical engineers pass the design to the electrical engineers, who dimension the drives and motors. Afterwards, the control unit is programmed. Only during testing does it become clear whether the routines work or not. In the worst case, you hear a bang because a step was overlooked or the kinematics are not right. Rectifying defects on the real machine is risky, expensive and jeopardizes the success of the project. Are there any alternatives? The US packaging manufacturer WestRock, with the assistance of Bosch Rexroth, has managed to minimize test risks and drastically reduce the time-to-market using simultaneous workflows.
Customized packaging lines in record time. Packaging manufacturer WestRock set out to do no less than this. Represented in 30 countries, their portfolio also includes customized plant engineering. The reason: in the beverage trade, new packaging is constantly clamoring to win the purchaser’s favor. The more appealing the design, the higher the purchase probability. Yet the cycle rates of Coca Cola and co. are high; custom packaging lines must be planned, developed and put into operation as quickly as possible.
In the meantime, WestRock is rushing on ahead of the competition, because the company relies on model-based engineering and simulation for development – not only for the packaging lines themselves, but from the packaging idea right up to transportation in the truck.
Packaging design with plausibility check
Using a virtual supermarket, the designers at WestRock test what might eventually be found on the shelves before production even begins. They place various types of packaging on shelves and shopping trolleys, determine the optimum weight for buyers, and use this to derive conclusions for the product design. Before WestRock presents the new repackaging to the beverage manufacturer in the virtual supermarket, the production planning checks the data using the simulation software and subjects it to a plausibility test. Among other things, this involves checking the outlay and unit costs at which the new packaging would be produced by the machines.
Value creation with consistently digital workflow
At WestRock, all design data flows into the 3DEXPERIENCE platform from Dassault Systèmes right from the first CAD mouse click. With the aid of simulation, the control program along with all drives and kinematics can be tested and optimized before a fitter even lifts a screwdriver and assembles the first parts of the production line. Automation partner Bosch Rexroth supplies the respective 3D and behavior models of its components such as servo motors and drives as standard, meaning complete virtual images of the installed components are available in just a few steps. All departments involved in the design process can now transfer their expertise at an early stage into a shared digital model, the digital twin, and work on this.
Virtual commissioning: pixels crash instead of steel
Once the customer has signed off on the product design, the fine tuning begins. Even then, no machine modules are assembled. Because first, the engineers test and optimize the axis movements in their digital model, which displays the machine infrastructure including the dynamics 1:1. Because the Motion Logic Control that is used as “hardware-in-the-loop” in the machine later also controls the simulated model, the system can even be virtually commissioned using 3DEXPERIENCE. This enables lengthy coordination processes during the test phase to be eliminated, unlike the conventional procedure. Synchronicity and thresholds can be tested safely, without exposing the design to the risk of damage. It’s better to crash pixels than steel, as the motto goes. The WestRock engineers use the findings gained from virtual commissioning to optimize the control program directly in the engineering environment IndraWorks.
Open for simulation results
The requirements for virtual commissioning and the associated shortening of the development process are enabled with Open Core Engineering. The accompanying Open Core Interface connects the real controller to the digital twin of the 3DEXPERIENCE platform, meaning it can interpret and correctly implement data and commands from the simulation. If the machine is later commissioned at the customer’s site by the technicians, time-intensive optimizations are redundant. This way, WestRock not only significantly reduces the development time, but the manufacturing costs too.
Retrofitting at the click of a mouse
To enable the packaging lines produced by WestRock to be adapted to ever shorter product life cycles and ever smaller batch sizes as quickly and flexibly as possible, the company is shifting more and more functions from mechanics into software. Using IndraWorks and the open interfaces and standards of Open Core Engineering, the software for this can be set up in just as modular a way as the hardware. For programming, WestRock uses PLC languages in accordance with IEC 61131 and PLCopen modules. However, standard languages are also available thanks to the Open Core Interface.
Pre-defined technology functions
In order to be able to implement more complex functions quickly and easily, pre-defined technology functions must also be provided. These no longer have to be programmed by the engineers, merely parameterized. The range includes camshaft controllers, simple actuation of stepper motors and flexible electronic FlexProfile cam disks. If a parameter is changed, all drives of the affected drive group in the model are automatically adapted.
Over 80 control cabinet-free servo drives
WestRock demonstrates another trend with a new packaging line which uses over 80 intelligent servo drives that do not require a control cabinet from the IndraDrive Mi range. They save installation space and reduce the amount of cabling work. In the future, the power supply and grid connection of the drive technology will also no longer require a control cabinet. This will save a considerable amount of space in the control cabinet. With “Safety on board”, additional intelligent safety functions in the drives will make the line even safer and easier to operate. WestRock shows this at the drinktec in Hall A2 Booth 502 together with Bosch Rexroth in a demonstrator. Several IndraMotion MLC with SafeLogic functions assume the control of the servo motors and additional modules. They are connected to one another via Sercos real time cross communication, which guarantees high synchronicity in the entire line.
With its consistently digital workflow based on model-based engineering with Bosch Rexroth and Dassault Systèmes, WestRock was able to significantly reduce the development time and in so doing respond more specifically and quickly to customer demands. Besides reduced manufacturing costs, financial benefits also result in day-to-day operation. The designers can now also model servo motors and axis movements right from the outset. The control logic arises in parallel to this and is seamlessly integrated into the model of the digital twin as part of the virtual commissioning. The result of individual commands immediately becomes visible in the 3D simulation. Because the work preparation can also simulate and calculate the subsequent production processes in advance, WestRock has very little outlay in beginning production of the packaging plant after the order has been issued. A striking advantage in an industry in which each day saved in the run-up to the product launch counts.