Machine speak

It is the critical link between man and machine, and has a vital position in the modern process plant.

So what’s next in the evolution of the human-machine interface (HMI) for control systems?

According to process equipment suppliers, an effective HMI should alert operators long before process problems can take hold and then offer intuitive controls to quickly remedy the situation.

The information displayed on those screens must go beyond the schematic to more compact visualisations of information from across a wider scope of responsibility to direct the operator to what needs attention and what needs to be done

Honeywell’s Jason Urso

But some of the old infrastructure that still persists in many process control operations has been standing in the way of progress.

“For many years now, the operator’s console has been built primarily around schematic displays that present information in terms of the structure of the plant and process,” says Jason Urso, chief technology officer of Honeywell Process Solutions.

He says this can present a number of drawbacks when it comes to controlling processes.

“Because the schematic-based display model presents information in terms of the structure of the process, it can require operators to navigate through several displays to find information they need to fully understand a situation,” he says.

Presenting information via an array of monitors can also create a disjointed visual experience, he adds.

The traditional keyboard and mouse create additional hurdles as operators often juggle several devices in order to navigate information and perform process actions.

The solution, according to Urso, comes in the form of larger, ultra-high definition displays with flexible and unified information layouts.

“The information displayed on those screens must go beyond the schematic to more compact visualisations of information from across a wider scope of responsibility to direct the operator to what needs attention and what needs to be done,” he says.

This was the thinking behind the release of its Experion PKS Orion console earlier this year.

Andrew Stuart, Control Room product manager at Honeywell Process Solutions, says Orion is the natural next step in the evolution of HMI in the control room.

What is critical to operators, says Stuart, is the need to know whether the processes delivering their key revenues are going up or down.

“Rather than show a picture of the plant, we are displaying a graphic that leads them to running the plant in an optimal way,” he says.

The other widely reported issue is speed of response, says Stuart.

“Operators have found that running a modern control system with a mouse and keyboard is not the optimum solution,” he says.

“One operator said to me: ‘I have got to make five changes in two minutes when the plant trips, which can cost us millions of dollars’.”

He says this frustration was behind the development of operator touch panels that Honeywell aims to release next year.

“It will give them back that touch response,” says Stuart.

“Touch is everywhere and it is the future.”

The other issue highlighted by operators was their long shifts, which often made them feel quite isolated.

Honeywell’s answer is a tablet-sized HMI which they can take away during quiet periods, and still maintain a situational awareness of the control room, says Stuart.

According to the ARC Advisory, innovations such as these are becoming increasingly sought-after capabilities for HMI.

“Today, many end users and OEMs want more than what the traditional HMI software has provided in the past,” says ARC’s European research director, David Humphrey.

“There are changes in the way the leading edge of users are deploying HMI software, including smarter HMI design, broader use of HMI visualisation to improve different categories of business decisions, and distributing real-time data to all levels of the manufacturing organisation through workflow and other complementary technologies.”

Karl Walker, automation product marketing manager at Omron Electronics agrees that HMIs are becoming much more than a simple display device.

The company’s NA-series HMI is a touch panel designed to work alongside its Sysmac automation platform.

“It’s fair to say that the HMI has become the nexus of the machine, simplifying even the most complex processes,” says Walker.

This might include simplistic graphical representations of errors that could be linked to a video that walks operators through the recovery process or key component replacement, he says.

The HMI’s presentation can also determine the fate of the process equipment it interacts with.

“Even if the machine incorporates cutting-edge technology with superlative design, performance and build quality, a poorly executed, counterintuitive set of operator control screens, which lack ergonomics and aesthetics, can convey the impression of a poor quality machine,” he says.

He adds that being in the age of smartphones and tablets, screen size, number of colours, pixel count and graphical capability are becoming increasingly important to users.

“Although the industrial market has never traditionally mirrored the fastmoving consumer market, attitudes are changing,” he says.

“These ‘bells and whistles’ are now expected.”

Walker sees future HMI’s incorporating the same technology found in consumer devices that use Omron’s OKAO ‘face vision’ detection and recognition technology, for “visual authentication of different levels of operator and maintenance personnel”.

“The same cameras could also help to identify causes of machine errors by providing a visual audit trail of operator actions,” he says. “They could recognise behaviour and intention, and consequently alert to problems before they even occur.”

Andy Courtney, Advantech’s industrial automation sales manager, says process visualisation is key to HMI technology.

“It is about having something visual in front of you with good resolution.”

However, he says mobility and touch are also increasingly important.

“In addition to advances in screen technology, you have the internet of things, and cloud computing, and these are changing how people interface with information and use visualisation displays,” he says.

“With the advent of the iPad, the expectation of multi-touch and gesturing plays a big part now. Our customers expect it to be there. I’m not saying touch is a substitute for hardwired switches in a safety-critical situation, but in time they could be.”

Advances in haptic technology are also likely to feature in future products, says Courtney, with onscreen keyboards offering a feel that is more like a physical keyboard.

“This will make a big difference for data input because it combines a familiar data interface with the flexibility of touchscreen,” he says.

According to researcher Frost & Sullivan, touchless sensing technology represents the next paradigm in HMI.

“With advanced touchless sensing technologies like gesture sensing, voice commands, brain wave sensing and eye tracking coming to the fore, the application potential of these solutions has expanded considerably,” says the researcher’s recent report on Touchless Sensors Technology.

But not everyone wants a cutting edge solution says Fabio Melegazzi, product manager at Telestar Automation.

“Some customers are moving towards new generation HMIs with features like those of smartphones or tablets, but others choose to stick with old style interfaces using keypad and numeric display,” he says.

“[This is] because they don’t need touch screen capabilities or these are not compatible with their application.”

Telestar Automation distributes Unitronics products as part of its range, which features a palm-sized PLC with inbuilt HMI which has been tailored for use in clean environments.

“The HMI must be bright and sharp with good contrast because the customers must be able to see very clear data not only in front but also from an angle,” says Melegazzi.

“We consider Unitronics [devices] as some of the best.”

But whichever device they choose, Melegazzi says the most important aspect is their ability to “match existing processes with current and future production goals and keep the operation running smoothly”.