31-01-2012, 02:37 PM
MOBILE AUGMENTED REALITY-REALIZATION
[attachment=16910]
INTRODUCTION
Augmented reality (AR) is a term for a live direct or indirect view of a physical real-world environment whose elements are augmented by virtual computer-generated imagery. It is related to a more general concept called mediated reality in which a view of reality is modified (possibly even diminished rather than augmented) by a computer. As a result, the technology functions by enhancing one’s current perception of reality.
In the case of Augmented Reality, the augmentation is conventionally in real-time and in semantic context with environmental elements, such as sports scores on TV during a match. With the help of advanced AR technology (e.g. adding computer vision and object recognition) the information about the surrounding real world of the user becomes interactive and digitally usable. Artificial information about the environment and the objects in it can be stored and retrieved as an information layer on top of the real world view. The term augmented reality is believed to have been coined in 1990 by Thomas Caudell, an employee of Boeing at the time.
PRIOR WORK IN MOBILE AUGMENTED REALITY
A recent demonstration of an outdoor mobile augmented reality application running on a cell phone is Nokia’s MARA project by Kähäri and Murphy . The system does not perform any image analysis, instead it uses an external GPS for localization and an inertial sensor to provide orientation. PhoneGuide is one of the first object recognition systems performing the computation on a mobile phone, instead of sending the images to a remote server
EXAMPLES
Commonly known examples of AR are the yellow "first down" lines seen in television broadcasts of American football games using the 1st & Ten system, and the colored trail showing location and direction of the puck in TV broadcasts of ice hockey games. The real-world elements are the football field and players, and the virtual element is the yellow line, which is drawn over the image by computers in real time. Similarly, rugby fields and cricket pitches are branded by their sponsors using Augmented Reality; giant logos are inserted onto the fields when viewed on television. In some cases, the modification of reality goes beyond mere augmentation.
HISTORY
• 1957-62: Morton Heilig, a cinematographer, creates and patents a simulator called Sensorama with visuals, sound, vibration, and smell.
• 1966: Ivan Sutherland invents the head-mounted display suggesting it was a window into a virtual world.
• 1975: Myron Krueger creates Videoplace that allows users to interact with virtual objects for the first time.
• 1989: Jaron Lanier coins the phrase Virtual Reality and creates the first commercial business around virtual worlds.
• 1992: Tom Caudell coins the phrase Augmented Reality while at Boeing helping workers assemble cables into aircraft.
HARDWARE
The main hardware components for augmented reality are: display, tracking, input devices, and computer. Combination of powerful CPU, camera, accelerometers, GPS and solid state compass are often present in modern smartphones, which make them prospective platforms for augmented reality.
HEAD MOUNTED DISPLAYS
A Head Mounted Display (HMD) places images of both the physical world and registered virtual graphical objects over the user's view of the world. The HMD's are either optical see-through or video see-through in nature. An optical see-through display employs half-silver mirror technology to allow views of physical world to pass through the lens and graphical overlay information to be reflected into the user's eyes.
