For some years now, there has been a steady increase in control complexity in the production environment. Conventional operating concepts follow the complexity through a multitude of interaction elements and control levels. Experienced users are spending more and more time navigating through the menus of machine controls in order to issue the appropriate commands or extract the right information from the flood of data collected. For new users, this means long training periods, a high risk of frustration and uncertainty in handling the system. In the industrial environment, there is a need for more intuitive operating systems, such as those already used in the consumer market, and for a stronger focus on the needs of the user.

In a study published by the Fraunhofer IAO on the production work of the future, 661 companies were surveyed on current topics: 73% of all companies surveyed see great potential in the use of mobile devices and 47% believe that the documentation effort can be drastically reduced with mobile devices. In the near future, it can be assumed that the interaction between man and machine will increase significantly and that an efficient interface between machine and man will become increasingly important. A large number of sensors will also make it increasingly possible to incorporate the context into information processing.

Application-oriented design

The development of a usable human-machine interface is an iterative process. It should begin with a detailed description of the activities to be carried out and the relevant user groups. The second step is to describe the information requirements for each user group in the respective work context: Who uses the interface in which situation for what? In step three, the hardware components and software tools used by the user to access information and carry out operating steps are defined. Finally, the overall solution is implemented so that each user only has access to exactly the information and operating options required for the respective work step.

Modern HMI systems should be designed in such a way that only authorized persons have access to certain data and information.

© WZL of the RWTH Aachen

Large amounts of data can be collected from the means of production and the production process. If this data is not processed automatically, it must be filtered and channeled. After all, the user requires significantly less information for his work process than the data collection generates. Ideally, the user has all the information he needs to complete the task without being irritated by superfluous information. When preparing the data, it is therefore important to fully capture the context of use and thus the information requirements. To do this, each individual user is assigned to a user group, known as a role. After creating a role-based profile that contains all role-specific work tasks, each task can be assigned a role-specific information requirement.

With the help of an additional context level, the interaction location (position), the information requirement can be further limited. The system (the machine, the installation) can now actively and individually support the user according to his current information requirements, knowing the role, the task and the position. Three aspects should therefore be included for a comprehensive context description:

■ the user's current work task (to support action-oriented dialogs):
■ the user's role (to derive authorization/views);
■ the user's location.

A work task often consists of several, sometimes sequential work steps that the user must complete in the correct order.

Action-oriented dialog presentation

The larger the HMI device, the greater the information content. However, the opposite is true for flexibility.

© WZL of the RWTH Aachen

For frequently recurring, standardizable processes, the individual steps can be mapped in the operating system, resulting in an action-oriented dialogue design in the form of task-specific workflows. In this way, even inexperienced users can work through complicated work steps in the correct sequence without having to search for the corresponding functions. Experienced users can also benefit from an action-oriented dialog design. In production operations, for example, processes are often monitored by a machine operator who regularly moves away from the machine to prepare for further activities. With the help of a smartwatch, they can monitor the status of the machine even when they are absent and are automatically notified of upcoming work steps.

Eaton's Galileo visualization software offers many options for configuring operating and visualization dialogs that are only available to certain roles. For example, it is possible to block sensitive areas of the user interface for web access. In addition, a web user can be given a different start page than a user who logs into the system locally.

The importance of the position

Location information can be a helpful addition to the complete description of the context of use. This allows dialogs to be called up automatically when entering certain areas. For example, a service technician could be shown a corresponding error message on a mobile display device when approaching a machine tool with a fault. If required, he can then display the relevant data, such as the error log, directly on his smart device and react accordingly. Another application is the location-specific configuration of messages and operating options. By defining zones, certain messages or operating elements can be activated or deactivated on the smart device. Typical smart devices, such as cell phones and tablets, are not necessarily designed for industrial use. Falls from normal working heights can cause considerable damage. In addition, you usually need both hands to operate them, which further limits their manageability. Smart watches could therefore represent an interesting alternative in the future. One suitable localization technology is the use of iBeacons, which are based on the widespread Bluetooth Low Energy (BLE) standard.

The increasing complexity of system control and the ever-increasing flood of data make an expansion of classic input systems urgently necessary. User-friendly, user-friendly and intuitive human-machine interfaces not only save time in the work process, but can also reduce the susceptibility to errors in operation. However, structural challenges - such as the definition of user roles and profiles - and technological challenges - such as filtering data according to definition and actual requirements, intuitive menu navigation, customizable controls or mobile interfaces - must be mastered, for which developers and users should work closely together.

Author: Stefan Selke is Marketing Manager MOEM at Eaton.

White Paper

Further information on this topic can be found in the white paper "Human-machine interaction in the production environment - design and development of user-friendly operating systems", which was produced in collaboration with a team of authors led by Prof. Dr. Christian Brecher, Head of the Machine Tool Research Department at the Machine Tool Laboratory WZL at RWTH Aachen University. It can be downloaded free of charge at Eaton.com/en/HMI.