Conveying, packaging, bottling, labeling. These applications represent the high-performance segment of the motion control market—that part of the market where high speed, high accuracy, and system configuration flexibility are paramount. Meeting such objectives requires ever tighter integration between motion and sequential control.
It comes as no surprise, therefore, that two of the world's biggest suppliers to the motion control market have recently announced new strategies for integrated motion control. Presented as complete motion solutions, Kinetix™ from Rockwell Automation and "Simotion", from Siemens Automation & Drives (see side story), are designed to eliminate the "mix-and-match" factor of traditional motion control systems. That means no time-critical interfaces be-tween components, and no associated programming or diagnostics.
In the past, machine builders have pursued a variety of strategies in the effort to better integrate sequential control and motion control, explains Brian Casey, director of global marketing for industrial motion control, Rockwell Automation. Examples include communication networks that may or may not have sufficient bandwidth; discrete I/O connections through the sequential controller and motion controller; and highly customized software working in a soft PLC or soft controller environment, or a PC card-based motion controller environment.
"Regardless of the approach," says Casey, "the system designer still ends up with completely different programming environments, completely separate databases, and a very difficult time tying a snapshot of the entire machine state into a larger architecture." With Kinetix, he claims, "the motion and sequential databases are one-in-the-same, and information access between the two is instantaneous."
For example, in a vertical form, fill, and seal (VFFS) application, Kinetix allows users to link, via fiber optic cable, a 1756-M08SE SERCOS Interface™ Motion Module to the multiple Ultra3000 SERCOS Servo Drives on-the-feed servo axis and one on-the-crimp servo axis. MP-Series Low Inertia Motors reside on both axes due to the high acceleration and deceleration of machine mechanics, as well as their compact size. Machine operators can use PanelView connected to the ControlLogix™ platform via EtherNet to change recipe information and monitor actual machine characteristics.
Furthermore, with the Kinetix integrated motion solution, users receive complete motion configuration and programming within a single automation control programming package using Rockwell Software's RSLogix™ 5000 software. This, says Casey, eliminates the need to purchase and maintain separate motion, sequential, and drive programming tools. Built-in motion instructions also eliminate the need to wire and coordinate two separate programs on different controllers, simplifying application programming and enhancing system performance. Other Kinetix benefits include:
Expansion flexibility. Modular memory, networking, and a multiprocessor architecture allow users to size the controller to specific application requirements.
Fast installation. Compared with an analog terminal block, Kinetix uses a fiber optic SERCOS interface connection between drives and controller resulting in fewer axis module cards and no external breakout boards to mount. Two fiber-optic connections can replace 18 discrete wires per drive, eliminating 36 terminations per axis.
Easy troubleshooting. Detailed drive and motor status information is available in RSLogix 5000 and the ControlLogix application program. Graphical trending and remote diagnostic capability also facilitate troubleshooting.
High performance. A high-resolution feedback option in the controller improves positioning accuracy and reduces motion cycle time. An absolute feedback option eliminates time-consuming homing cycles. Digital commands replace range-limited analog signals, while the integrated controller design eliminates network delays and synchronization logic.
Open operation. An IEC1131-based programming environment, support for the emerging PLV open standard for motion control function, and the SERCOS interface enhance openness.
"The foundation of Kinetix," Casey summarizes, "was a recognition that most machines on the market offer some sort of built-in sequential control along with motion control. Typically, the more axes of motion control, the more complex the sequential control that goes along with it. Because Rockwell was in the position of having mastery of both of those application competencies, Kinetix became an effective effort on our part to link the two together and connect the control of both sides into a common environment."
The result: complete solutions for industry involving all elements of integrated motion. The greater the integration between the PLC side of the equation and the motion side, the greater value of Kinetix.