In recent years, continuous improvements in motion control technology have led to higher levels of expertise among machine manufacturers, resulting in improved operational processes for machines in many industries. For example, previously, the printing industry used mechanical coupling between different color printing stations, achieving synchronization through a single main drive shaft; now, electronic gear coupling via controllers fundamentally eliminates this mechanical dependence. In the labeling industry, open-loop stepper motors and drivers are gradually being replaced by closed-loop position servo drivers and motors, eliminating potential stepping losses or positional inaccuracies associated with stepper motors. With the development of electronic gear and servo technology, the entire motion control platform as a system has undergone significant changes.
Today's motion control systems offer packaging machine manufacturers numerous functions and improvements. The combination of controllers, servo drives, and motors now enables more stable systems, resulting in better machine performance in terms of precision, speed, etc., higher output per unit time, longer uptime, shorter manufacturing time, less maintenance, and easier troubleshooting.
Digital networks, as an integral part of the system, are common in many current controllers. Compared to the analog command interfaces of traditional controllers, these digital networks are typically based on Ethernet communication protocols for deterministic data exchange between the controller and servo drives, operating synchronously at microsecond rates to enable real-time access to drive I/O and parameters. It's important to understand that these I/Os and parameters change rapidly during machine operation. Because of the reduced number of interface cables—effectively a plug-and-play network using standard Ethernet CAT5E shielded cables—they offer better noise immunity than analog systems. This characteristic also facilitates the placement of drives in the most suitable locations around the machine, enables modularity, and allows manufacturers to add options to basic machines with virtually no interface issues. In short, digital networks offer significant advantages over analog networks.
Printing presses and labeling machines are very similar, both having several unwinding stations and one or two rewinding stations. Materials such as paper or plastic are unwound from the rollers and fed into the machine, or exited the machine and rewound onto the rollers, whose diameters continuously increase or decrease. As the diameter changes, the roller's inertia also changes. Fluctuations in inertia generate different servo loop adjustment values for different diameters to prevent loop instability. In analog systems, it might be impossible to change this parameter while the machine is running. However, in digital network systems, these values can be accessed and changed by the controller, allowing for real-time control of the dynamically changing machine.
Because of the need for digital communication with the controller, the driver must also become more intelligent, just like the controller. Many drivers today are manufactured using DSP (Digital Signal Processing) technology, offering superior speed and processing power compared to older driver technologies. Most modern servo drivers also have built-in safety circuitry, allowing the driver and controller to be easily integrated into the machine's safety logic system.
Although servo motors have small bases, their output torque is considerable. Direct drive motors can be directly connected to loads like printing cylinders, eliminating the need for gearboxes and other mechanical mechanisms required by traditional belt-driven systems. Because the entire control system enhances the machine's productivity, corresponding improvements are also needed in other non-motion operations, such as those connected to the machine, and the activities and management of the workshop or enterprise where the machine is located.
For this reason, many control systems have embedded Ethernet TCP/IP communication to integrate devices into control systems such as I/O, vision systems, RFID readers, barcode scanners, and robots, and to exchange data with other control platforms, PCs, OPC clients, and SCADA systems.
For design engineers, this systematic approach is a welcome improvement. Since motion control suppliers typically offer comprehensive product lines, design engineers can now design machines almost entirely from a single manufacturer, rather than choosing from numerous different suppliers, each responsible for a portion of the design, and then spending considerable time and effort piecing everything together. Design engineers can focus on the design problem without worrying about resolving any interface issues. This also reduces the number of suppliers and duplicate orders. The advantages are obvious—seamless connections between components are possible in the machine assembly shop. The ease of debugging and troubleshooting also improves the level of technical service.
Therefore, a motion control system is your best choice.
