 Investigations description --- Augmented Reality 2 different Head-Mounted-Displays ARVision3D from Trivisio; dataGlass2A from Shimadzu, controlled by 2 PC will be used. The first HMD is a monocular optical see-through OST HMD: it is equipped with a semi-transparent LCD display for one eye. The user can directly see the physical world without limitations regarding the peripheral field of view. The second HMD is a binocular video see-through VST HMD: it is equipped with two LCD displays and a stereo camera system that records the physical environment and replays the video onto the displays in real-time. 