Tips to increasing the usability of your HMI application

HMI application
An HMI is a visual invitation to interaction. This is where things get done – starting, monitoring, reading or adjusting – by you or someone else. And the usability of the HMI determines how well we can execute our tasks.

Usability is about ensuring that the job, whatever it is, gets done efficiently, and with satisfaction. In stand-alone consumer applications and complex industrial settings alike, the same principles for creating a user-friendly and efficient interaction apply. Here are a few tips on how to guarantee usability in your HMI project:

1. Put yourself in the operator’s place

Before you start designing HMI screens, get a clear picture of the needs and limitations of your users and of the environment the application will work in, for example by observing existing applications in use or by interviewing operators. Many aspects influence how operators will communicate with the system, and therefore also how the interface should be designed, e.g. the experience level of users, language barriers, industry and cultural conventions, lighting conditions, special circumstances like wearing gloves, etc.

2. Visualize and test the workflow

Draw up the work flows of operating your application; which are the main tasks that must be accomplished, which are rarely performed, etc. Consider how the HMI should be laid out to make it as efficient as possible to execute the needed tasks – and test your sketches on the intended users.

3. Create your HMI project – design tips: Lead the way

Help the operator see what’s most important or guide towards the next step in the task at hand by using contrasts in text fonts or button styles to show which is the next expected action. Utilize colors and animated objects in the same manner to attract and direct attention. Acknowledge the operator’s actions by changing contrasts on buttons or giving an affirmative; this helps build trust and confidence in the system. However, the golden rule is that less is more; use in moderation and only add as much content as is needed to execute the task at hand. Too many visual elements or too much information clutters the screen and makes it difficult for the operator to maintain focus.

Utilize what’s already known

Use the generally acknowledged symbols in your particular field, as well as the commonly accepted rules for, e.g., the meaning of colors, button symbols and similar to avoid confusion and to provide the user with dialogs that are understood and familiar. Increase brand recognition with your customers by personalizing your application and creating a consistent company look throughout your product range using styles and screen templates.

Repeat symbols and layout

Apply the same button style, font types, color scheme, screen layout etc. throughout your project, and be consistent in their meaning and the action connected to them. This way, users quickly learn where buttons and objects are positioned and what they mean, and can focus on the operational tasks.

Keep the screens tidy

Alignment of objects is an easy way to make a layout appear visually easier to use. Align objects vertically and/or horizontally to create order and a clutter-free screen. Place multiple objects symmetrically to help the user recognize functional groups.

Group items carefully

Objects that are placed as a group, or just in near proximity of each other, are also perceived as being connected in function. Utilize this to enhance the relationship between, e.g., several parameters shown from the same engine. Objects that are unrelated should not be placed together to avoid confusion, and also beware that if objects are designed so that they look alike, people will also perceive that they belong together functionally. If the project requires that a lot of information must be presented in one screen, smart menus and pop-up dialogs can help the user quickly get an overview of what’s most important.

“As machines and hardware become increasingly generic, the usability of your solution is an opportunity to differentiate your solution from the competition”

iX HMI – made for usability

iXBeijer Electronics' iX HMI software was developed with providing smart tools for the creation of efficient operator interfaces in mind. With a “what-you-see-is-what-you-get” design approach, developers can picture the final result and easily test workflows. The software also offers smart tools to help display large amounts of information as well as keeping a consistent design throughout the HMI application. Similarly, it’s easy to implement your corporate design profile throughout all of your HMI applications. With support for C# scripting and third party components, iX offers endless opportunities for customizing not only look and feel but also functionality to the specific needs of your application.