Immersive 3D visualization laboratory concept
In the paper an advanced concept for a Virtual Reality (VR) CAVE installation is presented, which should allow for human immersion in a spatially unlimited virtual world. The CAVE will be completed by the end of 2013 in a special building designed and constructed for the purpose. The unit will simulate an autonomous movement of a human inside a computer generated scenery. The person immersed in VR space will be placed in a transparent sphere with a large diameter supported on rollers and equipped with a motion tracking system. Walking motion of the person will inflict the revolution of the ball and trigger changes in the computer generated images on screens surrounding the sphere thus creating an illusion of motion. The projection system will be equipped with a 3D simulation capability and supplemented with a spatial sound generation system.
Image Projection in Immersive 3D Visualization Laboratory
In recent years, many centers in the world attempted to build a virtual reality laboratory. The main idea of such laboratory is to allow the user to “immerse” into and move in a computer-generated virtual world. In the paper, the underlying principles of the system of virtual reality (VR) are described. The selected implementations constructed by the research centers of the world are also presented. The cave automatic virtual environment (CAVE) installation is planned to be implemented at the Gdansk University of Technology. In this solution, the images will be projected on flat screens arranged in the form of a cube. The user will be located inside a transparent sphere freely rotating inside a cube, which allows simulation of free movement without changing the position of the screens. A walking motion of the user will trigger changes in the computer-generated images on screens surrounding the sphere thus creating an illusion of motion. The problems of visualization in the planned installation are outlined and discussed.
Simplified impedance design and control for low-cost high-speed channels
Impedance design is the fundamentals of signal integrity at the very beginning, but controlled impedance is always costly or time-consuming for the high-speed channels. In this paper, many simulations of channel parasitics were taken and calculated that met with the specified impedances and correlated to the measurements very well. Selection of the different substrate stack-up without any layout modification in the BGA package reversed from the failed verification to pass the differential return loss. Adjustment of lead widths and spaces in the limited room of leadframe package improved 6 Ω of differential-mode impedance compared to the conventional leadframe packages. The differential pairs with wider traces routed on the 2-layer PCB are more robust for over-etching effects whose impedance errors are less than 5% without special impedance control. Moreover, those pairs inserted with a thin ground trace achieved 90 Ω differential-mode impedance and 28.2 Ω common-mode impedance simultaneously with 35% less routing area for MHL application and reserved a 10 Ω series resistor for ESD protection. With those diligent designs, the leadframe package and the 2-layer PCB can be still adopting in the consumer electronics for high-speed applications.