MOTION SYSTEMS HANDBOOK
Human-machine interfaces (HMIs) in evolution from operator terminals
HMIs and other operator interfaces and terminals function as software and hardware access points between machine and personnel. In some cases, components called operator interface terminals or OITs (consisting of pushbuttons, LEDs, switches, and hard keypads and small and moderately customizable displays) have yielded to HMIs. The latter in the context of factory and machine automation today usually refers to full ruggedized touchscreen electronics and memory loaded with operational recipes; advanced connectivity options; signal and data processing capabilities; and the ability to display relevant information and menus (even across multiple screens) to human operators. In fact, HMIs initially evolved from man-machine interfaces (MMIs) as well as graphical user interfaces (GUIs) into iterations accepting input beyond simple text — with the touchscreens just mentioned for image-based interfaces the world now takes for granted. Even HMIs from a few years ago are being superseded by new HMI hardware and software systems capable of supporting IoT functionality — usually by letting operations make more use of plant and machine data (data handling) in increasingly automated operations as well as remote operations. Such HMI functions also include system real-time supervision, event logging and triggering, diagnostics, and enterprise-
level monitoring. HMI integration with any existing supervisory control and data acquisition (SCADA) and manufacturing execution systems (MES) is key here. Where HMIs serve as a machine’s centralized controls, there is either connection to or integration of a PLC or motion controller. These controls serve to process axis feedback and I/O data for higher-level uses. Many HMIs today run real-time operating systems (OS); a few even include electronics with what’s called an asymmetric multi-processing (AMP) architecture. In contrast with common symmetric multiprocessing (SMP) architecture that runs a single OS across all CPU cores, AMP architecture lets the HMI run different OSs — usually as general-purpose logic on one CPU core and realtime controls on the other. That lets the control logic maintains real-time operations while HMI logic executes data collection, batch processing, and display tasks.
IDEC Corp. HG2G-V5 5.7-in., HG3G-V8 8.4-in., HG3G-VA 10.4-in., and HG4G-VC 12.1-in. touchscreen HMIs are suitable for both new and retrofit applications. 86
DESIGN WORLD — MOTION
HMIs — Motion Control HB 08-19 V3.indd 86
8 • 2019
motioncontroltips.com | designworldonline.com
8/19/19 11:02 AM
