Abstract: A device for creating a milieu for a creature in a real environment to the creature, the milieu comprising both at least one part of the real environment and at least one fictitious phenomenon, the properties of the milieu experienced by the creature depending on its position and/or orientation relative to the real environment. The device comprises a member for generating stimuli, the member including a transducer arranged to determine its position and/or orientation relative to the real environment by receiving incident optical signals and recording the relative incident directions of the received signals in relation to the transducer, and an element by which the creature and the transducer are connected for generating the stimuli by information about the position and/or orientation of the transducer and about the real environment, and a unit for transferring the generated stimuli to the creature.

Abstract: A device (4) for producing information concerning one or more properties of an environment (1), comprising a sensor (5) movable in relation to the environment, for obtaining information from the environment by recording or measuring one or more properties of the environment in one or more positions and/or directions, and a transducer (6) mechanically connected to the sensor (5) so that the relative positions and orientations of the sensor and the transducer are fixable. The transducer (6) is arranged to determine its orientation and position with respect to at least four degrees of freedom relative to the environment by receiving incident signals from signal sources (7) in the environment and thereby produce corresponding information concerning the orientation and the position of the sensor, for at least one said recording or measuring accomplished by the sensor (5).