techflash

Advances in handheld HMI

April 12, 2007
With the expanded capabilities of handheld HMIs, the functionality of built-ins can be obtained, but with some portability and less cost. Read how in this latest installment of Tech Flash.
A year ago, we examined the unfulfilled promise of handheld HMI. Few industrial OEMs pushed its use as a machine interface unless pressed by a customer. Lack of robustness was cited as one reason; ease of use—­­­­­­­­actually, its lack thereof—was another.

Despite this general perception, there’s been consistent use by some niche machine builders who construct certain types of mechatronics, such as robots, cranes, hoists, gantries, etc. These mechatronics require frequent reprogramming or must be taught specific operations. Now, with the expanded capabilities of many handhelds, the functionality of built-ins can be obtained, but with some portability and less cost.

Another look at recent advances might put this in perspective. For example, QSI Corp. now offers a smorgasbord-type selection process to allow customers to configure its QTerm-G55 handheld HMIs the way they want them. Customers can select NEMA4 or NEMA12-rated units. Choices in keypad and screen configurations address the ease-of-use issue. All come with QSI’s object-based programming language, Qlarity.

Siemens E&A sees a significant market for handheld HMI products, and its latest offerings seem to address many machine builders’ concerns. Siemens now offers more robust Mobic industrial WebPad handheld data monitors and Simatic Models 177 and 277 mobile panels, which are more an extension of built-in HMIs and conventional OITs.

The latest Mobic designs include industrial hardening to meet the demands of severe industrial environments, more memory, a faster CPU, higher resolution screen, better ergonomics, additional communication ports, and longer battery life. Docking stations can be placed throughout a factory for charging. New battery technology reportedly holds a charge for eight hours.

Physical communication ports now include not only a serial port, but also an Ethernet TCP/IP port. Wireless communications also are included. The operating systems on all Siemens handhelds is embedded Windows CE.

The Simatic mobile panels, on the other hand, are configured for machine-mounted junction-box docking and mobility up to 25 m via an umbilical cord. “The trend towards mobility allows for standardization,” stresses Jay Coughlin, Siemens’ HMI products manager. “The mobile panels are positioned to offer machine builders more space-savings and operator flexibility.” This handheld design also ties-in nicely with modular machine design because of built-in diagnostics and new, self-correcting software. These mobile panels now offer a desktop-like  interaction with multiple machines.

The new diagnostic and self-correcting software in the mobile panels includes Sm@rt Access and Sm@rt Service. The former provides machine programming changes and diagnostics locally, while the latter offers diagnostics remotely via a built-in web browser.

Software Horizons takes a more straightforward approach through a “design once and deploy anywhere” philosophy. Its InstantHMI platform supports Windows CE, touch panels, PDAs, and smart phones (Windows Mobile). The HMI project (tag database and screen objects) can be designed once and deployed anywhere on any of the supported platforms without modification. The PDA-based InstantHMI doesn’t require a PC as a server.

“Our view of ‘plant’ allows for plants to be outside and distributed, as well as inside the four walls of a factory,” says Ramal Murali, Software Horizons’ president. “While PCs in the framework of data historians are excellent workhorses for collecting huge amounts of data, the InstantHMI philosophy is to enable ‘discrimination, integration and distillation’ into the data collection and analysis process. PDAs bring mobility, flexibility, and agility to the data-collection process.”

InstantHMI handhelds maintain information in a tag database. Graphical display of screen objects presents the requested information. Moreover, InstantHMI units such as Symbol-PowerFlex and iROC provide a communication interface to link screen objects with data sources such as machine-mounted sensors. They also include several tools for data logging and trend viewing that might be useful in the machine data analysis. Communication protocols supported include wireless IR and RF (Wi-Fi) technologies, and Bluetooth RF options.

The HMI software onboard, in conjunction with a wireless link to relevant information, offers a huge assistance in isolating critical subsystems that need immediate attention. This critical information can be logged for later analysis, and also can be accessed remotely via cellular network or Internet.

  About the Author
Loren Shaumis principal at Comtec, Syracuse, Ind., which provides research in the machine and general factory automation markets. You can reach him at[email protected].