Future-proofing your HMIs

With the advent of the Internet of Things (IoT) and Industry 4.0, the growth of connected devices will force changes in HMI technologies. And in many applications, HMIs will be running on embedded operating system platforms, another major development.

With the arrival of IoT and Industry 4.0, the number of embedded devices connected to HMIs will grow exponentially, along with corresponding increased functionality requirements. These requirements will include connection to any device regardless of connection protocol or network, and the ability to handle very large numbers of connected devices and the data they will provide.

Interoperability is an essential characteristic for components of an efficient system based on IoT and Industry 4.0. In this context, the HMI software can assume a much broader role than it has in the past. 

The HMI needs to be able to enable communication among devices operating on different protocols. These devices include, but are not limited to, smart sensors, controllers and remote I/O. Not only must the HMI software support multiple standards, such as OPC UA, it must also support the proprietary protocols often found in hybrid systems. 

As the HMI will be connected to multiple device types, it must be able to manipulate the data, filter it and apply pre-defined rules in order to optimise overall communications. The HMI will need to transform raw data into meaningful information, or possibly even provide advanced data analysis in systems with a higher level of sophistication. 

In addition to communication among the devices (the things in the IoT) physically located on the plant-floor, pipeline, RTUs, etc, the HMI is also becoming the gateway between local devices and cloud-based systems. These cloud-based systems consolidate information and typically run analytics to enable or positively influence decision-making. In many cases this interface requires an efficient way to send and retrieve data from remote databases – a part of a Big Data system.

Once these devices are connected, they will no longer be stranded on an island, but will instead be an integral part of the automation system and supply chain. This growing number of connected devices will need an HMI with the portability and small footprint to operate on any platform and operating system.

Most HMIs installed in industrial plants run on Windows-based PCs or Windows Embedded operating systems. While these host systems will continue to be important, other platforms are emerging due to their lower costs and reduced resource requirements.

There are several operating systems that have a large piece of the pie. Windows Embedded Compact, formerly known as Windows CE, has a strong position in the industrial HMI market. VxWorks has nearly 40% market share in traditional real time operating system shipments. Linux has more than 25% of all embedded shipments, and it has even more when including Android, which is loosely based on Linux. 

While each of these operating systems has specific niches, advantages and certifications, they are all suitable for embedded platforms running HMI software. These operating systems and their host platforms allow hardware manufacturers to create disk images with small footprints and the minimum components required for their specific purposes. This is different from traditional operating systems, such as the desktop/server market, that have a much larger footprint, and correspondingly high resource requirements such as processing power and memory. 

In a high-volume market such as embedded platforms – cost, power consumption and reliability have substantially higher importance than in the desktop/server PC market. In these critical areas, embedded platforms often deliver substantial advantages as compared to industrial PCs. 

Consequently, your HMI software development package must provide the scalability, portability and footprint required for deployment on a wide variety of operating systems and platforms. 

The user experience when working with an HMI starts with development on a Windows-based PC, where a rapid application configuration environment is essential. During this phase, the ability to use the same development environment to create HMI applications for any operating system or platform should be available.  

The HMI development software should also provide a high level of integration, and simple sharing of interfaces among all deployments regardless of the platform or operating system. Many hardware manufacturers design proprietary HMI software for their specific hardware and operating system. This holds customers hostage to their combined hardware/software solution, and it imposes substantial constraints when applying standards across different platforms. 

By contrast, platform-agnostic HMI software can be compiled to run on virtually any major embedded platform as designs are created in an open environment. This increases portability to different platforms and improves return on investment in both the short and the long term by integrating hybrid platforms in a seamless manner.

Another important characteristic of HMIs for IoT and Industry 4.0 systems is the ability to access information through rich graphical interfaces hosted in thin clients, usually web browsers. Many embedded platforms are ‘blind’ and do not include a local display, and even those with integral displays are often located in remote or difficult access areas, making remote browser-based access a necessity. 

These browsers run in remote PCs, or on mobile platforms such as tablets, PDAs and smartphones. This browser-based remote access will typically be used for configuration and diagnostics, and for monitoring and control.

Consider specifying an HMI package that can connect to and exchange data with devices in use today, and with those anticipated for the future. These devices will include wired and wireless sensors, and all manner of embedded platforms. Along with connection to these devices and platforms, handling the increased data they will provide is also important.

Today most HMIs run on PCs or embedded Windows platforms. However this is rapidly changing with the widespread deployment of many different embedded operating systems. Consequently, easy development for and deployment on all of these operating systems needs to be supported by the HMI software development package.

Fabio Terezinho is InduSoft director of consulting services/product manager at Wonderware by Schneider Electric.