Space robot commanding and supervision by means of projective virtual reality: The ERA experiences

The symbiosis between computer graphics and modern planning and control methodologies is the basis for the development of projective virtual reality based telepresence techniques at the IRF. Virtual worlds appear close-to-reality for the user because of the interaction modeling techniques borrowed from the field of robotics research. These techniques provide an intuitively operable user-environment for a great range of applications. The underlying idea of projective virtual reality is to first let the user work in a virtual world modeled after the physical plant to control and supervise. A projective virtual reality system then automatically deduces the impact of the user's actions on the state of the virtual plant and in turn employs action planning methods to generate the equivalent impact on the physical plant using robots or other means of automation. Thus the robots are "projecting" the user's actions From the virtual into the physical world. The developed Projective Virtual Reality System is of especially great use for space applications. For the German/Japanese project GETEX (German ETS-VII Experiment), the IRF realized the telerobotic ground station for the free flying robot ERA on board the Japanese satellite ETS-VII. During the mission in April 1999 the Virtual Reality based command interface turned out to be an ideally suited platform for the intuitive commanding and supervision of the robot in space.