2. Contents 1. Introduction Introduction 2. Virtual Reality (VR) Virtual Reality (VR) 3. VR v/s AR VR v/s AR 4. Need for Augmented Reality (AR) Need for Augmented Reality (AR) 5. Design Design 6. Challenges Challenges 7. Applications Applications 8. Future Prospects Future Prospects 9. Conclusion Conclusion 10. References References 2

3. 1. Introduction Augmented Reality : An Augmented Reality system generates a composite view for the user. It’s a combination of the real scene viewed by the user and a virtual scene generated by the computer that augments the scene with additional information. AR systems have the following three properties: 1. Blends real and virtual, in real environment 2. Interactive in real time 3. Registered in 3D 3

4. 1.1 AR View 4

5. 2. Virtual Reality (VR) “A computer generated, interactive, three- dimensional environment in which a person is immersed.” Requires high performance computer graphics to provide an adequate level of realism Blocks out all the external world and present to the wearer a view that is under the complete control of the computer 5

6. 3. VR v/s AR Virtual Reality  Totally immersive environment.  Completely immersed in an artificial world and becomes divorced from the real environment  Visual senses are under control of system Augmented Reality  System augments the real world scene  User maintains a sense of presence in real world  Needs a mechanism to combine virtual and real worlds 6

7. 3.1 Reality-Virtuality Continuum 7 Milgram’s Reality-Virtuality Continuum  The real world and a totally virtual environment are at the two ends of this continuum with the middle region called Mixed Reality.  Augmented Virtuality -> systems which are mostly synthetic with some real world imagery

8. 4. Need for AR  For some applications, it may be desirable to use as much as possible real world in the scene rather creating a new scene using computer imagery. Eg. Medicine and telerobotics  Can maintain the high-level of detail and realism that one finds in the real world.  AR enhances real world, while VR replaces or simulates the real world 8

9. 5. Design The four components of any AR system are 5.1The Display System (usually an HMD) 5.2The Tracking System 5.3Mobile Computing Power 5.4Input device (usually a wrist mounted keyboard) 9

10. 5.1 The Display System  Allows the user to see the image and text created by the Augmented Reality Systems There are basically two types of display systems: 5.1.1 Optical see-through 5.1.2 Video see-through 5.1.1 Optical see-through displays Direct viewing of real world through naked eye Uses optical combiners- partially reflective, partially transmissive Similar to HUDs used in military aircrafts 10

11. 5.1.1 Optical see-through display 11

12. 5.1.2 Video see-through display Combination of closed-view HMD and one or more head-mounted video cameras Video from camera combined with graphic images created by the scene generator 12

13. Advantages of Optical see-through display Simplicity- cheap and simple (one video stream). Resolution- user’s real world view is not retarded Safety No eye offset 13 Advantages of Video see-through display Flexibility in composition strategies Wide field of view Real and virtual view delays can be matched Additional registration strategies Easier to match brightness of real and virtual objects

14. 5.2 The Tracking System Used to find the position and orientation of the viewer Where the user is located with respect to his surroundings Movement of user’s head The two main functions of tracking system:  Find the person’s position in space  Using the three Cartesian coordinates- x, y and z  Find the direction in which the person is looking  Using three angles- pitch(or elevation), roll and yaw(azimuth) 14 These are called six degrees of freedom (DOF)

15. Tracking System (contd) The six degrees of freedom 15 Positive pitch- upward head tilt Positive roll- left head tilt Positive yaw- left head rotation 2 conventional tracking devices used:  Hi-ball Tracking System(for indoor applications)  GPS (for outdoor applications)

16. 5.3 Mobile Computing Power Ideal computing device – wearable computers  Freedom in movement  Ergonomics  Ruggedness (depends on the application) Features:  Portable while operational  Hands-free use  Attention getting  Always ON 16

17. Mobile Computing Power (contd) 17 Eg. Xybernaut Wearable Computer  HMD  CPU module  Wrist-mounted Keyboard

18. 6. Challenges/Design Issues 6.1 Display Issues  Focus and contrast  Eye offset  Field of view 6.2 Registration Issues 6.3 Tracking Issues  Sample rate  Update rate  Latency 6.4 Portability Issue 18

19. 6.2 Registration Issues 6.2.1 Static Errors  Optical Distortions  Mechanical misalignments  Incorrect viewing parameters(FOV, interpupillary dist.) 6.2.2 Dynamic Errors  System lag (latency) 19

20. 6.3 Tracking Issues  Sample rate- rate at which sensors are checked for data  Update rate- The rate at which the system reports new position coordinates to the host computer  Latency(or lag)- delay between the movement of the remotely sensed object and the report of the new position 20 6.4 Portability Issue  The user moves around  Ergonomics (when mounted and used for a long duration)  The power consumption should also be at minimum since the system is to run on batteries to facilitate portability

21. 7. Applications 7.1 Medical  Training aid – Virtual instructions for a novice surgeon  Surgery – ultrasound imaging 7.2 Manufacturing and repair  Machine assembly – Instructions as 3-D drawings superimposed upon the actual equipment 7.3 Military  BARS- Battle Field Augmented Reality System  Military Aircrafts-HUDs and HMSs 7.4 Annotation and Visualization  Used in sports – to name or point out cars in a race 7.5 Entertainment  Games – the most recent one being an AR version of the popular game Quake- ARQuake 21

22. 7.1 Applications: Medicine 22 A tumor surgery Laparoscopy

23. 7.2 Applications: Manufacture/Repair 23 Laser Printer Assembly 7.3 Applications: Military BARS

24. 7.4 Applications: Annotation 24

25. 8. Future Prospects AR has a wide vista of applications in store for future:  Medical:In minimal invasive surgeries, endoscopy, laparoscopy  Collaborative Applications: Military- BARS  Commercial Applications: Ads, games and sports-Race F/X  Tourism: ARCHEOGUIDE- helps tourists with info. Implemented in Greece on a test basis.  Multimodal displays (haptics and auditory interactions) 25

26. 9. Conclusion AR systems are far behind VR systems in terms of maturity. Augmented Reality is a relatively new field, where most of the research efforts have occurred in the past few years. Because of the numerous challenges and unexplored avenues in this area, AR will remain a vibrant area of research for at least the next several years. After the basic problems with AR are solved, the ultimate goal will be to generate virtual objects that are so realistic that they are virtually indistinguishable from the real environment. 26

27. 10. References [1] Ronald T. Azuma, “A Survey of Augmented Reality”, Presence- Teleoperators and Virtual Environments, Volume 6, pp. 355-385, 1997 [2] Ronald T. Azuma, Yohan Baillot, Steven Feiner, Simon Julier, “Recent Advances in Augmented Reality”, IEEE Computers Graphics & Applications, Volume 21, November 2001 [3] Claudio Kimer,Ezequiel R. Zorzal, Tereza G. Kirner, “Case Studies on the Development of Games Using Augmented Reality”, IEEE International Conference on Systems, Man and Cybernetics, October 2006 [4] Lyu M. R, King I, Wong T. T, “ARCADE: Augmented Reality Computing Arena For Digital Entertainment”, Aerospace Conference 2005 27

28. 28 THANK YOU…..