User interface

The user interface ( according to society for computer science, Department of Human- Computer Interaction and User Interface) is the location or action, a man enters with a machine in contact. In the simplest case, this is a light switch: it belongs neither to the people nor to the " machine" ( lamp), but is the interface between the two.

Systematically examines the user interface is one of the man-machine systems ( MMS): Human ↔ ↔ man -machine interface machine. Various studies dedicated to the subject, such as computer science, cognitive science and psychology.

Thus, a user interface for humans is usable and useful, they must be adapted to his needs and abilities. The basic knowledge for an ergonomic and user-friendly interface design will be developed in the scientific discipline of ergonomics. The specific areas of activity are here Cognitive Ergonomics, ergonomics and system software ergonomics ( usability engineering).

• 4.1 I & C
• 4.2 Guidelines

Man-machine interface

The user interface is also called " man-machine interface " (MMS ) or English " Human Machine Interface" ( HMI) or " Man Machine Interface" ( HMI) called and allows the operator may pass over the operation of the machine, the monitoring of the plant states and the intervention in the process. The provision of information ( "Feedback") either via control panels with signal lamps, display fields and buttons or by software via a visualization system running on a terminal, for example. When the light switch is the visual feedback from the impression of "light" and the position " a " or " dark " and "off". The driver's side of a car has numerous User Interface - of the control devices ( pedals, steering wheel, shift and turn signal lever, etc.) to the optical feedback of the "machine " Auto ( displays for speed, range, radio program, navigation system, etc.).

Examples

Photographs

Modern man-machine interface of a ICEs

User interface of a Japanese toilet

Voice-enabled user interface to Google Glass

MMS for audio mixing

MMS for the post-production ( film )

MMS in a sugar factory

Emergency stop button

Schemes

Different human-machine interfaces require each custom software implementations.

Success and failure of user interfaces

The success of a technical product depends not only on the factors price, reliability and service life, but also the factor of handling and ease of use. Ideally, a user interface intuitively explained by itself, ie without training. The light switch is, despite its popularity and simplicity is not an ideal user interface, but the compromise of a target conflict. This is that the switch should be mounted directly on the device to be switched on one hand, so on the lamp itself ( so you do not have to look for it). On the other hand, it should be near the door of his ( where he is usually ), so you do not have to grope in the dark until after the lamp.

An equally popular but also not ideal interface is the touch-sensitive screen: Here you will for example by touching the screen icon for email on the program that collects the e-mail. However, while you press on the icon of the finger conceals the icon itself, this usually creates no problems, but the precise painting or writing with fingers on the screen is impossible.

With durable products over the years the user interface are optimized. So today lacking in players for audio or video two switches that were still in the 1980s usual: The functionality of the switch for the jump to the previous or next track were integrated into the switch for fast forward or rewind. For this, the user interface is more complex because each of the two buttons now performs two functions. When the developers of user interfaces, the reduction as in this example plays a central role: the reduction of access to a complex machine to only a few controls may facilitate basic usability, but is most often does not do justice to the complexity.

At the very complex operating systems of modern computers to solve this conflict by two categories of user interfaces: one shows the user for everyday use, the icons, the trash, the folders, and so he understands without learning expense immediately and can operate: Clicking on a Link to example opens the destination web page. The other allows him via the command line interface, a deep intrusion into the computer system, however, requires a high learning curve. Thus ended about taskkill / F / IM iexplore.exe all connected to the Internet Explorer processes on a Windows system.

Characteristics

Because can pose a significant risk of many machines, to a man-machine interface to be as clear and unambiguous, that they can be operated safely in a panic. Therefore, special demands are placed on the emergency stop switch. International standards IEC / EN 60073 (VDE 0199), IEC / EN 60204-1 (VDE 0113 Part 1) based on indicator lights on the familiar colors of traffic signals on the road and guided by the fact the colors of the keypads of push buttons from. The colors in display columns machines to be used in the order shown.

In addition, symbols are provided in accordance with IEC 60417-5007, for example:

Such symbols are advantageous due to the widespread color-vision deficiency, but as some warning signs explanation.

Computer-based user interface

A computer-based user interface or user interface, actually user interface which is part of a computer program communicates with the user. In DIN EN ISO 9241-110, the concept of the user interface is defined as " make all components of an interactive system ( software or hardware), the information and controls available, which are necessary for the user to perform a specific work task with the interactive system to be done. "

There are the following types of computer-based user interface:

• Representational user interface (English Tangible User Interface, abbreviated TUI) In this (newer) approach, the system functionality is embodied in physical objects, and through this at the same time controlled and read. A mouse is in the strict sense no TUI, because it is simply a generic input device.
• Brain -computer interface (English Brain Computer Interface, abbreviated BCI) Enables operation of a computer via thoughts, ie without the use of the extremities. A wide range of applications can be found in the support of people with physical disabilities.
• Graphical user interfaces (English Graphical User Interface, abbreviated GUI) With graphical user interfaces can be designed complex surfaces that can be operated with the mouse, optional but also with other input devices usually. KDE or Aqua are examples of GUIs. In GUIs, the interaction elements are often represented as icons ( icons). GUI icons are symbolic- pictorial metaphors and have their origin in the office world of the 1970s.
• Command line (English Command Line Interface, abbreviated to CLI) Command line require that the user enters the appropriate commands from the keyboard. Command line interpreter (English Command Line Interpreter, abbreviated also CLI) are an example of the command line. At the beginning of computer history CLIs were the only user interface, so the more general term shell is still often used as a synonym for command line.
• Natural user interfaces ( engl. Natural User Interface, abbreviated NUI ) Natural user interfaces such as a touch screen are berührempfindlich and respond to finger and hand movements. The gesture-based operation is in sympathy with natural, habitual movements and allows an intuitive handling of interactive devices. A digital, artificial entry system ( such as mouse or keyboard) falls away, instead recorded and interpreted the surface of the touch of the user.
• Voice-enabled user interface (English voice user interfaces, abbreviated VUI ) About voice-based user interface the user via the spoken word to communicate with a system. Expenditures consist of either übermitteltem from prerecorded sound or from a synthetic voice text. Inputs require a speech recognition or a combination with other input paradigms such as text entry, mouse click or DTMF signals to phones. An example of a VUI are language dialogue systems, interactive telephone message services and dialing systems.
• Perception- driven user interface (English Perceptual User Interface, abbreviated PUI ) This approach is still in development. Among other things, the Fraunhofer Institute for Digital Media Technology employ, as well as the junior research group "Perceptual User Interfaces" at the Max Planck Institute for computer science Saarbrücken with this issue. By combining GUI, VUI and electronic communication gesture recognition should be facilitated with the computer.
• Character-based user interface (English Text User Interface, abbreviated TUI) Character-based user interfaces are text based, but do not require a command input from the user, but usually present themselves in the form of menus that are served with the keyboard and rarely with the mouse. An example of a text user interface is the file manager Norton Commander.

Although the user interface may, but need not necessarily contain any of the lower levels; Thus, the Midnight Commander has integrated such as a shell, but still belongs to the text user interfaces.

Menus are independent of whether a user interface is designed graphically, textually, aurally or otherwise.

Such a visualization system often consists of a PC with a monitor and a keyboard and mouse. Some systems require a company-specific computer, most of which can be implemented on an ordinary PC.

Control

Configurable computer-based user interfaces provide for measurement and control (including Supervisory Control and Data Acquisition, SCADA briefly ) the communication and exchange ( process visualization ) between a PLC and the people safe and are thus an integral part of a control system.

Typical of a SCADA system is the central alarm management, archiving of data, preparation of time schedules and a messaging service (SMS, e-mail, text-to -speech). A SCADA contains an HMI system as a user interface. Some of these systems, such as InTouch or WinCC contain an integrated graphics editor and a plethora of industrial icons such as motors, valves, pipes or switch.

With the keyboard, mouse or the control information, the symbol objects can then be changed depending on the programming.

Due to individual screen objects, graphics and pages then created a user interface, which represents the functions and stored data of the machine.

Guidelines

The provider of a computer operating system usually published as part of the documentation to a set of standards designed for the standardized design of the user interface, English as a Human Interface Guideline or style guide. It is often the principles of software ergonomics are taken into account. An application software will also be judged on how well they comply with this standard.

Such policies are known, for example from OpenStep (Apple, NeXTSTEP, GNUstep, etc. ), IBM ( Common User Access), GNOME, KDE, Java Swing and Windows.