Usability: Installation of Interactive Virtual Environments

Abstract
Installation of interactive virtual environments to evaluate questions on usability in the field of work safety.

Introduction
A badly designed human-machine-interface frequently leads to operation errors. The human-machine-interface is often designed in a way that leads the user to cognitive misinterpretations which in turn result in mistakes. The task of this research project was to investigate exemplarily to what extent it would be possible to conduct directed usability tests on working machines without any real threat for the subjects.

Implementation
At first a model and simulation of a lathe (Virtools / Ogre) was done and displayed in the Immersion Square. On top of that the display and steering of a lathe were reproduced using the input device of a real lathe (SINUMERIK MCP 483) and an industrial keyboard (activated via gamepad-controller), as well as the dynamic sound of the machine and the background noises. We evaluated this new virtual lathe by investigating subjects (lathe operaters) including surveys.

Results
The major question of this research project, if it is possible to conduct investigations on work safety of machines in a virtual environment, can clearly be confirmed. In favor of this are both the performance data (match of performance with predicted degree of difficulty of the task) and the high acceptance of the investigation by the subjects.

Another result of the concluded research project is that in future investigations on work safety in a virtual environment there should be a special focus on the quality of the display. This applies especially for the resolution of the display, the perspective (best solution would be a variable perspective, provided by head-tracking) and the synchronization of sensory characteristics of different sensory organs (vision, audio, etc.). It was shown, that dangerous situations on working machines can be simulated, so that it is now possible to investigate secure solutions in a safe environment. It is for example possible to conduct directed investigations of safety mechanisms in virtual reality to figure out if they work properly or if they handicap the user. Safety mechanisms that constrict the user with his work are often manipulated. These manipulations cause severe accidents which shows the importance of constructing the mechanisms very carefully.