The HMI of the future will look very familiar
HMI/SCADA applications enable companies to benefit from commercial off-the-shelf technologies adapted for industrial automation to lower costs and improve operations.
Ever since PC-based software was introduced to industrial automation, the once very separate worlds of commercial off-the-shelf (COTS) and industrial technologies have become more aligned. Many readers will remember when PC-based software was first introduced for HMI/SCADA systems in the mid-1980s. At the time, there were concerns with reliability and speed of response, but PC-based software is now the de facto standard when it comes to HMI packages, both for operator interface and SCADA applications.
HMI applications now routinely run on both office-grade and industrial PCs, and the software used to program these applications is also PC-based. At the same time, SCADA technologies are advancing to enable manufacturers to reduce costs through the use of COTS applications (see Table 1).
The word “influence” is important because industrial automation devices are not and will not be duplicates of COTS devices. An industrial PC may have the look and feel as well as some of the underlying technology of a COTS PC, but it’s also designed to withstand the demands of harsh environments, and often also includes other features to increase reliability such as solid-state data storage.
Just as desktops were replaced with laptops in many instances, laptops are now being replaced by tablets and smartphones with multi-touch technologies. This trend is also moving into industrial settings. In addition to the way we access HMI systems, the way data is manipulated and stored is being transformed by SCADA technologies for devices first developed for personal use.
Corporations are recognizing and reacting to these trends. A recent study by the Gartner research firm predicts that about half of the world's companies will enact BYOD (bring your own device) programs by 2017 and will no longer provide computing devices to employees.
The implication is clear: employees will be expected to use their own smartphones and tablets to access corporate computing systems, a move driven by both cost-saving potential for companies, and greater ease-of-use and mobility for their employees.
Faster, less expensive ways to access data
Smartphones and tablets are great products for today’s more mobile workforce as many employees are being asked to monitor and control multiple local and remote sites, often from home offices or while on the road. These workers need quick and easy remote access to HMI systems in order to make more informed decisions away from the control room, and what better way than to utilize devices that they are already intimately familiar with through everyday use.
One of the factors powering this movement is SCADA software that enables users to access automation systems as easily on their smartphones in the field as they do in the plant. Authorized users needing remote real-time access can be supplied with either read-only or two-way access, depending on their specific duties and responsibilities. From handheld devices, users typically access web-based HMI systems via a secure browser or an app. The server-browser option almost always comes standard with a web-based HMI package.
Many HMI/SCADA software packages also provide a type of server-mobile phone app for free or at a very low cost. As with SCADA server-browser platforms, remote users benefit from full-featured two-way communication. As compared to a browser, these SCADA apps connect more quickly to remote systems, load screens faster, and provide more rapid response times (see Figure 1).
Both browser and app access are much less expensive than providing access via a thin client or a PC connected to the corporate network, particularly if the company has adopted a BYOD policy. In addition, browser-based access doesn’t require any software to be loaded onto the mobile device, and app access only requires the user to load a simple app. This frees corporate IT from the task of supporting these devices, and further reductions in required support can be realized by adopting another COTS technology: cloud-based computing.
More affordable data storage
Once the domain of storing photos and music files, the cloud is now being employed as a repository for corporate data and software. But what exactly is the cloud?
Cloud computing provides 24/7 network access to a shared pool of configurable computing resources: networks, servers, applications, services, and storage. These resources can be quickly deployed and accessed with minimal effort on the part of the user. Most current cloud-based SCADA systems are configured with a local SCADA application running on a PC installed at the site, and with this PC connected to the controllers. The local PC is then connected to the cloud, sending data to the cloud where it’s stored and distributed, and receiving commands from the cloud as required (see Figure 2).
HMI/SCADA systems inherently generate tremendous amounts of data, and this data must be available for access by many users located in disparate and often widely distributed locations. Many of these users also need to be able to issue commands to HMI systems. This requirement for reliable and high-speed two-way wire and wireless access is an area where the cloud shines, as it has been applied to commercial applications with these requirements for many years.
Moving to a cloud-based HMI can significantly lower costs and enhance functionality. Users can easily view data via smartphones and tablet computers. They also receive alerts via SMS text messages and e-mail. Cloud computing also basically eliminates the high cost and problems of the hardware layer of IT infrastructure.
This new paradigm offers dynamic and affordable scalability, with potentially huge savings. Companies don’t need to spend money on software licenses, redundant hardware, and disaster recovery sites that may never be used. The cloud also lets companies quickly add new resources on demand only when they are needed, instead of designing systems upfront with excess capacity.
Until recently, data storage was a large required corporate expense as data often needed to be saved on separate servers housed in different geographical locations to provide secure backup, and IT staff were required to maintain and help provide access to the data. By contrast, cloud-based computing provides easy data archiving on a pay-as-you-go model by which users usually only pay for the amount of storage needed, with the cloud company providing all required backups and maintenance.