Abstract
In this article, a latest technology named as Augmented Reality (AR) is introduced and explained. What is Augmented Reality? How it links the real and imaginary worlds together? How does it work? Why is it significant? What are the applications of augmented technology? These are some common questions that raises in everyone’s mind when he/she hear about this new technology. This article will surely be very helpful to give all answers to your questions.Introduction
We all live in a world of technology. Scientists are moving their way to invent faster, more precise and expert technologies, in short they are going to implement all their imaginations in the real world. Just imagine a technology with the help of which you could see more than others see, touch more than others touch and perhaps even hear, taste and smell things that others cannot. What if we had technology to recognize completely computational elements and objects within our real world experience, entire creatures and structures even that help us in our daily activities? Our work would be faster than ever before due to that technology. We could do multi tasks and save our time. With such technology, mechanics could see instructions what to do next when repairing an unknown piece of equipment, surgeons could see ultrasound scans of organs while performing surgery on them, fire fighters could see building layouts to avoid invisible hazards, soldiers could see positions of enemy snipers, and we could read news and reviews in the street we’re walking in, Sports Umpires could take more precise and quick decisions, a gamer could play all 3D games in real world by emerging himself into that specific game environment. |
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Augmented reality (AR) is this technology to create a “next generation, reality-based interface” and is moving from laboratories around the world into various industries and consumer markets. AR supplements the real world with virtual (computer-generated) objects that appear to coexist in the same space as the real world.
Augmented reality (AR) is a live, direct or indirect, view of a physical, real-world environment whose elements are augmented by computer-generated sensory input such as sound, video, graphics or GPS data. It is related to a more general concept called mediated reality, in which a view of reality is modified by a computer. As a result, the technology functions by increasing one’s existing view of reality. By contrast, virtual reality replaces the real world with a simulated one. Augmentation is conservatively in real-time and in semantic context with environmental elements, such as sports scores on TV during a match. Artificial information about the environment and its objects can be overlaid on the real world.
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Research shows the application of computer-generated imagery in live-video streams as a way to augment the view of the real world. AR technology includes head-mounted displays and virtual retinal displays for visualization purposes.
Brief History
In 1960’s, computer graphics pioneer Ivan Sutherland and his students at Harvard University and the University of Utah created the first AR prototypes. To present 3D graphics they used a see-through. During the 1970s and 1980s a group of researchers at U.S. Air Force’s Arm-strong Laboratory, the NASA Ames Research Center, the Massachusetts Institute of Technology, and the University of North Carolina at Chapel Hill continued the research. In 1990s, the term “augmented reality” was introduced by Mizell and Caudell, scientists at Boeing Corporation who were developing an experimental AR system to help workers put together wiring harnesses. True mobile AR was still out of reach, but a few years later GPS-based outdoor system was developed that present navigational assistance. |
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By the late 1990s, as AR became a distinct field of research, several AR conferences began, including the International Workshop and Symposium on Augmented Reality, the International Symposium on Mixed Reality, and the Designing Augmented Reality Environments workshop.
Organizations were formed such as the Mixed Reality Systems Laboratory in Nottingham and the Arvika consortium in Germany. In the meantime, several surveys appeared that give an overview on AR advances, describe its problems, classify and summarize developments. By 2001, MR Lab finished their pilot research, and the symposia were united in the International Symposium on Mixed and Augmented Reality, which has become the major symposium for industry and research to exchange problems and solutions.
Displays
AR systems commonly apply human sensory inputs, sight, sound and/or touch. Various technologies are used in Augmented Reality rendering including optical projection systems, monitors, hand held devices, and display systems worn on one's person such as head mounted displays.Head-worn
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. Optical displays attached to the head include the video/optical see-through head-mounted display (HMD), virtual retinal display (VRD), and head-mounted projective display (HMPD). |
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Fig.4 shows examples of four (parallax-free) head-worn display types:
(a) Canon’s Co-Optical Axis See-through Augmented Reality (COASTAR) video see-through display
(b) Konica Minolta’s holographic optical see-through “Forgettable Display” prototype.
(c) Micro Vision’s monochromatic and monocular Nomad retinal scanning display.
(d) an organic light-emitting diode (OLED) based head-mounted projective display
Handheld
Handheld display AR promises to be the first commercial success for AR technologies. This kind includes hand-held video/optical see-through displays as well as hand-held projectors. Although this type of displays is bulkier than head-worn displays, it is currently the best work-around to introduce AR to a mass market due to low production costs and ease of use.Examples of Handheld can be seen in Figures below:
Fig.5 shows some Hand-held video see-through displays.
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Fig.6 shows Hand-held optical and projective displays.
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Spatial
Spatial Augmented Reality (SAR) augments real world objects and scenes without the use of special displays such as monitors, head mounted displays or hand-held devices. SAR makes use of digital projectors to display graphical information onto physical objects. The key difference in SAR is that the display is separated from the users of the system. SAR is more beneficial than HMD and Handhelds. Multiple people can use a system at the same time without wearing Head-mounted Displays.Examples of Spatial can be seen in Figures below:
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Fig.7(a) shows AR overlay that is presented on a transparent screen.
Fig.7 (b) shows 3D holographs that solve the alignment problem.
Tracking
Before an AR system can display virtual objects into a real environment, the system must be able to sense the environment and track the viewer’s (relative) movement preferably with six degrees of freedom (6DOF). Two things are important for tracking the user’s head: its position and orientation. Modern mobile augmented reality systems use one or more of the following tracking technologies: digital cameras and/or other optical sensors, accelerometers, GPS, gyroscopes, solid state compasses, RFID and wireless sensors.Applications of Augmented Reality
Augmented reality has wide range of applications in many fields and is much beneficial for them in usage. AR was initially used for military, industrial, and medical applications, but was soon applied to commercial and entertainment areas as well. Now AR is a major part of these fields because everything is computer generated. There are some major applications of Augmented reality discussed below:Personal Information System, Personal assistant and Advertisement
Höllerer and Feiner believe one of the biggest potential markets for AR could prove to be in personal wearable computing. A wearable gestural interface is developed at MIT, which attempts to bring information out into the tangible world by means of a tiny projector and a camera mounted on a collar.Personal Awareness as assistant which automatically stores names and faces of people you meet (fig.8). Speech recognition also provides a natural interface to recover the information that was recorded earlier. Journalists, police, geographers and archaeologists could use AR to place notes or signs in the environment they are reporting on or working in.
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Medical
Augmented technology has a great work to do with the medical field. The imaging technology has always been so pervasive throughout the medical field. Most of the medical applications deal with image guided surgery (Fig. 9). |
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Pre-operative imaging studies of the patient, such as CT (Computed Tomography) or MRI (Magnetic Resonance Imaging) scans, provide the surgeon with the necessary view of the internal anatomy. Surgery is planned from these images.
Visualization of the path through the structure of the affected area (where a tumor exists, for example) is done by first creating a 3D model from the multiple views and slices in the pre-operative study. The model is then projected over the target surface to help the surgical procedure. Augmented reality can be applied so that the surgical team can see the CT or MRI data properly.
There is also another application of augmented reality in the domain of medical field i.e. ultrasound imaging. The ultrasound technician can see a rendered image of the fetus overlaid on the abdomen of the pregnant woman using an optical see-through (fig.10 ).
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Sports and Entertainment
AR is commonly used in sports broadcasting. Sports and entertainment venues are provided with see-through and overlay augmentation through tracked camera feeds for enhanced viewing by the audience. Swimming pools, football fields, race tracks and other sports environments are well-known and easily prepared which video see-through augmentation through tracked camera feeds easy. This is augmented with computer generated maps using a technique called chroma-keying. The gaming industry has benefited a lot from the development of this technology, a number of games have been developed for prepared indoor environments. Now a player can be a real part of his game. Using AR tools, one can see the whole game environment around him and can enjoy the real battle field or 3D game environment. |
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Office Workplace
AR is also proved to be very helpful in office workplace. Many conferences are held with real and virtual participants among distributed team members through this technology. This all is done in an office environment created by AR. AR tasks can include brainstorming and discussion meetings utilizing common visualization via touch screen tables, interactive digital whiteboards, shared design spaces, and distributed control rooms.Navigation
AR can augment the effectiveness of navigation devices. Information can be displayed on the car's windshield indicating information of where the user is going and the information about the weather is also offered. AR can provide traffic information to drivers as well as alert the driver in case of an emergency or highlight objects on the road that might not be caught by the driver’s eyes at a first glance. It can also be used in the sea where fishermen can use the technology to display information about the amount of fish that are in the area and how to get to them.Now some car makers (e.g. BMW and GM) are also using this technology in car windshields to display meter information and traffic information.
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Military training
The military has been using displays in cock-pits that present information to the pilot on the windshield of the cockpit or the visor of the flight helmet (Figure 18). The pilot gets into the real environment and has all the emotions just as in real environment. This is a form of augmented reality display. By equipping military personnel with helmet mounted visor displays or a special purpose rangefinder the activities of other units participating in the exercise can be imaged. While looking at the horizon, during a training section for example, the display equipped soldier could see a virtual helicopter rising above the tree line. This helicopter could be being flown in simulation by another participant. In wartime, the display of the real battlefield scene could be augmented with annotation information or highlighting to emphasize hidden enemy units. |
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