The virtual touch - Haptische Rückkopplung in Virtuellen Welten

To meet the demands of complex VR applications state-of-the-art systems generate visual representations of virtual environments combined with acoustical feedback. But in some application areas, for example medicine or virtual prototyping, "seeing" and "hearing" is not sufficient. Thus, additional human perceptual channels have to be stimulated: the haptic senses. Consequently, the Fraunhofer IGD develops concepts on the integration of haptic displays into virtual environments. Haptic displays are devices which areable to feedback reaction forces and tactile stimuli as well as temperature and motion to the user. The additional feedback improves both the impression of reality and the capability to orientate oneself in virtual worlds. Furthermore, the development of two devices, a force feedback and a temperature feedback device, are described. Some of the projects with industrial partners strongly require the integraton of haptic displays. To satisfy these requirements a general approach to integrate haptic displays into our VR system "Virtual Design" will be described in the following chapters. To date we are working on adding force feedback to a certain VR application, the Virtual Reality Arthroscopy Training Simulator (VRAYS). Temperature feedback is used to simulate a spatial temperature feeling, e.g., a virtual fireplace. The three thermal phenomena conduction, convection, and radiation build the physical basis for the simulation o temperature feedback. The simulation process as well as the development of a device, the ThermoPad, will be described in more detail.