Industrial HMI software: simple use & straightforward visualizations

Due to the increasing complexity of the machines, it is becoming more and more important to be able to display a large amount of information in a small space. At the same time, however, this information must also be displayed in a way that makes sense to the worker according to ergonomic points, so that he can grasp and react to it quickly.

An HMI (Human Machine Interface) deals with two areas, on the one hand the clear display of information and on the other hand the simple operation of the machine.

HMI visualization as a challenge

  • Standardization: Due to the various manufacturer-specific solutions, there is no uniform design and operating concept, which hinders the operator and maintenance staff both in learning and in performing their tasks.
  • Flexibility: Restrictions due to manufacturer-specific hardware specifications for the operator terminal. Mostly use of a resource-intensive FAT client.
  • Transparency: Display of local machine and process data only, thus lack of transparency for the entire production.
  • Functionality: Fulfillment of customer requirements through the functional framework of the solution.
  • Integration: Connection of many different terminals in the production network (IT restrictions regarding security and total productive maintenance).

What is an HMI?

  • Human Machine Interface (HMI).
  • Execution via terminaldirectly on or next to the machine
  • Great differencesdepending on the type and complexity of the machine
  • Control and monitoringof various real-time data and functions of the machine
  • The more user-friendlyand demand-oriented an HMI module, the more efficiently the plant can be operated by the worker and used for digital shopfloor management.

levels of an HMI software: field, control, and operator level

HMI software overview

  • Decentralized perspective: Local operator terminal with plant-related visualization and operation
  • Server-based solution for graphical process visualization and process-related operation
  • Supports up to several hundred individual stations
  • Low latency (< 1 second) for production critical interactions: Data stream without detours via database
  • Rights concept for user-specific functions

Overview of the plant within the HMI software

HMI software designer as a graphic editor for the visualizations

  • Legato Graphic Designer based on function stack (xml-graphic files)
  • HMI Designer 100% web-based (cloud-ready) as an integral part of Legato Sapient
  • Standard libraries for graphic elements (e.g., process engineering ISO standard)
  • Direct loading, editing, and saving of graphic files on the server possible (no down-/upload required)

Editing the design within the HMI software

Transfer from edit mode to live view

  • The visualizations can be easily displayed in the Web Browser and
  • transferred to the MES system Legato Sapient for live view.

Transferring the HMI from the browser into the MES

Dynamic HMI software from MES data pool

  • Variables are linked to visualization elements via so-called “data bindings” and can dynamically change their style attributes
  • Dynamizations possible via simple calculations, logical operations, or mapping functions
  • Creation of project-specific visualization objects including function logics and saving as templates in customer-specific libraries

dynamic objects inside the HMI software

Using the HMI software designer


  • The machine supplier creates HMI projects
  • Providing a projecting environment in the cloud
  • Visualizations are stored directly in a directory
  • Creation of a file that assigns required variables


  • Local installation that connects to the cloud


  • Only HMI project and mapping table are required


  • AWS administration by Gefasoft
  • Vendor needs to work with browser and local setup is required once at the beginning

graphic representation of the connection of the HMI and the cloud

Look and Feel

  • A traditional design following detached application can be applied for high user acceptance or
  • a more modern design based on the look and feel of Legato Sapient.

Design options of the HMI software of Legato Sapient

FAQ: Frequently asked questions about HMI software

Learn more about HMI systems in our answers to the most frequently asked questions.

Where is HMI software used?

In principle, HMI systems can be found throughout everyday life. All automated processes that are operated by humans, be it the roller shutter, cruise control or vacuum robot, include an HMI module. In automated industry, HMI systems are used to control and operate machinery – so-called industry 4.0. In addition to manufacturing, HMI systems are used in the wastewater industry, energy industry and food industry, among others.

What does HMI have to do with SCADA?

An HMI module is a subcomponent of a SCADA system. It is an HMI module that directly controls and operates a machine. A SCADA system brings together all the HMI modules and collects and stores the data that they hold.