When designing an industrial process interface, the idea of a user’s situational awareness (SA) may arise within your team. At face value, it may just seem like another buzzword, but it’s a really important concept to grasp. At its core, situational awareness means taking the user’s context into consideration. How might their environment, attitude, personality, location, etc effect their interaction with your HMI design? Asking these questions at the beginning of a new industrial application project will save you countless headaches in the future.
Situational Awareness is User Context
As a designer or engineer creating an industrial application, understanding your users contexts is crucial. Your user’s situational awareness may include:
- Being aware of what is happening around them.
- Understanding what that information means to them now.
- Understanding what that information may mean to them in the future.
A user’s context relates to the goals and objectives of their specific responsibilities, as it relates to your SCADA application. Going a bit deep here, situational awareness really consists of these three levels.
Level 1: Perception of needed data
The status, attributes and dynamics of elements in the environment.
Level 2: Comprehension of the current situation
Comprehension is based on a synthesis of the disjointed Level 1 elements and a comparison of that information against one’s goals. Novices may not have the knowledge base to draw on and may be at a disadvantage when trying to develop Level 2 SA.
Level 3: Projection of future status
The ability to predict what will happen. This can only be achieved by having a good understanding of Level 2 SA, along with a highly developed mental model of the system. By understanding how operators select and use goals, designers can better understand how information is perceived. Without understanding the user’s goals on SA, the information presented has no meaning.
What May Effect an Operator’s Situational Awareness?
Situation awareness depends upon human information processing which is a complex process. Because of this fact, there are manny factors that may undermine an operator’s effective context and awareness in a situation. A few examples of these detractors of focus to look out for are outlined below.
Attention tunneling is the act of fixating on one set of information to the exclusion of others. This is the most common type of SA failure. A poorly designed SCADA interface may easily contribute to this through misuse of hierarchy, colors, alarming, etc.
Working Memory Traps
A fancy word for a very simple concept. Humans only have so much working memory that can be called upon during a task. When we rely on this limited short term memory to get through a complex flow or to complete a lengthy goal, the user is doomed to fail.
Workload, Anxiety and Fatigue
This type of barrier results in the reduction of a person’s capacity to process information. At its simplest, you have overworked operators or stressful situations which lead to cognitive fatigue. The Fatigue could also be physical, dependent on the operator’s context. Perhaps their eyes are strained trying to read small text, or are overloaded with alarms, trying to sort our which really matter.
A similar situation is that of data overload. This happens when overwhelming amounts of data can reduce a person’s SA. For example, text moves through our mental pipeline much more slowly than information presented graphically. Your HMI’s design may be unknowingly forcing the operator to do a lot of the mental math themselves when interacting with your application. An effective UX design and talking to operators about the goals with a SCADA system can help to alleviate this type of issue.
Flawed Information Architecture
Information architecture is the organization and hierarchy of your application’s data. Based on the application and user’s context, certain forms of information will demand more salience than others. What should call the users attention? If your HMI’s visual design conflicts with the apps core goals and the users principles, distractions will occur. For example, the color red, animations, and flashing lights can distract a person away from information that may be more important.
It’s difficult to develop an accurate mental model of how a system works when there are too many features. An application that spans thousands of screens and dynamically presents data to the user can quickly become overwhelming. Training, navigational design and repetition of use can help to reduce the complexity of any application. Additionally, user research and testing sessions may surface pain points that can be redesigned to ease operator stress.
The good news is that each of these flaws are avoidable with a compelling and well-executed interface design. Working alongside user experience design experts and researchers can shed compelling light on any potential problems before they arise. Getting an HMI design done correctly the first time around will save countless hours of frustration and rework in the future.
Was this article helpful? Consider purchasing the HMIcons Master Collection. It’s a sophisticated graphics library, purpose-built for industrial applications. With SVG vector industrial graphics of specific machinery and tools commonly found on factory floors, this illustration set will help you to design any interface, report, presentation or dashboard in the industrial automation industry. Level up your designs!