Module 1 VR.pdf
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Virtual reality is a medium that allows users to experience and interact with simulated environments. It uses interactive computer simulations to sense a user's position and actions to provide feedback to their senses, giving the feeling of presence in the virtual world. The key elements of a VR experience are an immersive virtual world, sensory feedback, and interactivity. A VR system combines hardware like head-mounted displays, software, and a virtual environment to produce the VR experience.
Module 1 VR.pdf
- 1. Virtual Reality Mrs. Rashmi Bhat Asst. Professor St. John College of Engineering and Management
- 2. Terms you should know... • The state or quality of being real. Reality • Being in essence or effect, but not in fact. Virtual 2 Prepared by Mrs. Rashmi Bhat
- 3. What is Virtual Reality? Virtual reality is a medium, a means by which humans can share ideas and experiences. • Experience convey an entire virtual reality participation session. • The part of the experience that is “the world” witnessed by the participant and with which they interact is referred to as the virtual world. • Virtual world can be • Virtual reality world • Contents of novels, movies etc. 3 Prepared by Mrs. Rashmi Bhat
- 4. Key Elements of VR Experience • Virtual world • Immersion • Sensory feedback • Interactivity 4 Prepared by Mrs. Rashmi Bhat
- 5. Key Elements of VR Experience Virtual World • A virtual world is the content of a given medium. • Virtual world can be defined as • An imaginary space often manifested through a medium. OR • A description of a collection of objects in a space and the rules and relationships governing those objects. • A virtual world can exist without being displayed in a virtual reality system. 5 Prepared by Mrs. Rashmi Bhat
- 6. Key Elements of VR Experience • Immersion • VR is an immersion into an alternative reality or point of view. • It is important to manifest the ideas of our imagination into some medium. • e.g. Novel, drama or movie • Each of these media produce only one-way communication: from creator to audience. • Mimesis: a writer's ability to pull the reader into the story. • There is no direct interaction between the viewer and the world • These media often present their worlds from a third person's point of view (POV). 6 Prepared by Mrs. Rashmi Bhat
- 7. Key Elements of VR Experience • Immersion • In VR, immersion is physical and mental. • Immersion is a sensation of being in an environment; can be a purely mental state or can be accomplished through physical means. • Mental immersion is a state of being deeply engaged; suspension of disbelief; involvement. • Physical immersion is a bodily entering into a medium; synthetic stimulus of the body's senses via the use of technology. • Physical immersion is a defining characteristic of virtual reality while mental immersion is probably the goal of most media creators. • Presence: sense of presence; being mentally immersed. 7 Prepared by Mrs. Rashmi Bhat
- 8. Key Elements of VR Experience • Sensory Feedback • VR allows participants to select their vantage point by positioning their body and to affect events in the virtual world. • What Reality is? • Imagined reality refers to the experiences we have in our thoughts and dreams or that we experience second- hand in novels, films, radio, and so on. • Imagining ourselves within the world presented through the medium known as the diegesis. • Physical reality is what we experience firsthand. • Virtual reality is the medium through which we can experience an imagined reality with many of our physical senses 8 Prepared by Mrs. Rashmi Bhat
- 9. Key Elements of VR Experience • Sensory Feedback • The VR system provides direct sensory feedback to the participants based on their physical position. • A typical VR system will track the head of the participant and at least one hand or an object held by the hand to generate sensory output. • Position tracking is the computerized sensing of the position (location and/or orientation) of an object in the physical world-usually at least part of the participant's body. 9 Prepared by Mrs. Rashmi Bhat
- 10. Key Elements of VR Experience • Interactivity • For virtual reality to seem authentic, it should respond to user actions i.e. VR should be interactive. • Forms of Interactivity • The ability to affect a computer-based world • The ability to change one's viewpoint within a world. • Interactive fiction (IF) can be defined in terms of the user/player's ability to interact with a world by changing locations, picking up objects and setting them down. • Virtual reality (VR) is more closely associated with the ability of the participant to move physically within the world, obtaining a new vantage point through movements of the head. 10 Prepared by Mrs. Rashmi Bhat
- 11. Key Elements of VR Experience Interactivity 11 Prepared by Mrs. Rashmi Bhat
- 12. Key Elements of VR Experience • Interactivity • Collaborative Environment • An extension of the interactive element and refers to multiple users interacting within the same virtual space or simulation. • The users' representations in a virtual world are referred to as their avatars. • Collaborative environment is where multiple users interact within a virtual world that enables interaction among participants. • A collaborative VR environment can be referred to as multi- presence or multiparticipant. • Avatar • A virtual object used to represent a participant or physical object in a virtual world • The object embodied by a participant. 12 Prepared by Mrs. Rashmi Bhat
- 13. What is Virtual Reality (VR) A medium composed of interactive computer simulations that sense the participant’s position and actions, providing synthetic feedback to one or more senses, giving the feeling of being immersed or being present in the simulation (a virtual world). 13 Prepared by Mrs. Rashmi Bhat
- 14. What is Virtual Reality (VR)? • VR can be developed by modern computer systems through additional hardware devices to provide user position sensing, sensory display, and programming of suitable interaction. • A typical VR system will substitute at least the visual stimuli, with aural stimuli also frequently provided. • A third, less common sense that is included is skin-sensation and force feedback, which is jointly referred to as the haptic (touch) sense. • Less frequently used senses include vestibular (balance), olfaction (smell), and gustation (taste). 14 Prepared by Mrs. Rashmi Bhat
- 15. What is Virtual Reality (VR)? • e.g. Head Mounted Display (HMD) • Graphic images are dis- played on a screen or a pair of screens (one for each eye) in the helmet. • A tracking sensor attached to the participant's head tells the computer system where the participant is looking. • The computer quickly displays a visual image from the vantage point appropriate to the participant's position. • Thus, the participant is able to look about a computer- generated world in a manner similar to the real world 15 Prepared by Mrs. Rashmi Bhat
- 16. What is Virtual Reality (VR)? VR Related Technological Terms: • Cyberspace • People who are physically located in disparate physical locations can, through the use of some mediating technology, interact as if they were physically proximate. • Telepresence • It is a means to virtually place a participant in another location in which they are not physically present. • The difference from VR is that this location is actually a real place that for one reason or another is too difficult, dangerous or inconvenient for the person to visit in person. • Augmented Reality (AR) • AR gives the user an altered view of the real world. • It is the visual sense that is augmented, providing the user with abilities such as peering through walls, or into a patient’s body. 16 Prepared by Mrs. Rashmi Bhat
- 17. VR Paradigms • There are multiple ways by which VR systems provide synthetic stimuli to the senses. • Three basic display paradigms hold for not only visual displays, but also for display to other senses such as aural and touch (haptic) display systems. • Stationary displays • Head-based displays • Hand-based displays 24 Prepared by Mrs. Rashmi Bhat
- 18. VR Paradigms • Stationary Displays • These are fixed in place. • The virtual world is rendered in response to the user’s bodily position. • e.g. CAVE-type systems, single large screen systems, and desktop monitors, • Loudspeakers are an example of stationary aural displays. The CAVE, participants stand surrounded by screens onto which the virtual world is displayed. 25 Prepared by Mrs. Rashmi Bhat
- 19. VR Paradigms • Head-based Displays • These displays move in conjunction with the user’s head. • No matter which way users turn their head, the displays move, remaining in a fixed position relative to the body’s sensory inputs. • Visual screens remain in front of the users’ eyes, and headphones on their ears. • e.g. HMDs, BOOM™-type displays • Headphones are an example of head-based aural displays. The BOOM head-based display mounts the screens on an arm that keeps the weight from being applied to the user’s head. 26 Prepared by Mrs. Rashmi Bhat
- 20. VR Paradigms • Hand-based Displays • Users hold the display in their hand. • For visual hand-based displays, monitoring both the user’s head position as well as the position of the display is required, because the direction of view is important. • e.g. haptic hand-based display SensAble Technologies PHANToM™ arm. A hand-based display to superimpose virtual models on a stationary scene. 27 Prepared by Mrs. Rashmi Bhat
- 21. Collaboration 28 Prepared by Mrs. Rashmi Bhat
- 22. VR Collaboration A set of processes, tools, and policies that encourage people to come together in a simulated virtual space where they can work together in real-time. • Participants can read and react to a co-worker’s facial expression, body language, and gestures, significantly reducing the risk of miscommunication. • Key Elements in VR Collaboration • Virtual world • 3D Avatar • VR Headset or VR Compatible device • Desktop streaming • Collaboration and productivity tools 29 Prepared by Mrs. Rashmi Bhat
- 23. VR Collaboration • VR environments can foster collaboration in a number of different ways. • Space can be shared, either physically or virtually. • Dialog can be held synchronously, or in an asynchronous form. • A major benefit of virtual shared spaces is that they allow collaboration to take place via computer networks. • In a networked collaborative environment, each participant can be represented as a virtual entity. • A virtual entity that represents a human in a collaborative environment is called an avatar. • Can be either realistic or abstract representation of the person. 30 Prepared by Mrs. Rashmi Bhat
- 24. VR Collaboration • Not every sense always needs to be transmitted in collaborative environments. • Collaborators can inhabit the shared virtual world concurrently and engage in synchronous dialog and actions, or participate asynchronously by saving the state of the system after their component of the collaborative activity. 31 Prepared by Mrs. Rashmi Bhat
- 25. Use Cases of VR Collaboration Brainstorming without location barriers Data visualization and data-driven decisions Collaborative 3D product design Education and enterprise training Employee engagement Social networking 32 Prepared by Mrs. Rashmi Bhat
- 26. Challenges in VR Collaboration • Last-mile connectivity • Gaps in global internet penetration could make it difficult for employees in certain regions to access VR • Data Privacy and Diversity & Inclusion (D&I) • Ethical discussions around employee data privacy and D&I in the VR world must be fully ironed out. 33 Prepared by Mrs. Rashmi Bhat
- 27. VR System • The creation of a virtual reality system requires the integration of • Hardware • Software • Virtual World • User Interface 34 Prepared by Mrs. Rashmi Bhat
- 28. VR System • Hardware • Computer/Graphics Engines • Display • Visual Displays • Aural Displays • Haptic Displays • Other Sensory Displays • Input Devices/User Tracking 35 Prepared by Mrs. Rashmi Bhat
- 29. VR System • Hardware: Computer/Graphics Engine • Responsible for calculating the physical behavior of the virtual world, • Renders the state of the world into visual, aural, haptic, etc. Representations. • Must require • Enough computational power • Ability to synchronize the display updates between multiple displays • Ability to render sounds • Ability to perform multiple operations at the same time • Can be • a single large computer that meets all the requirements • interconnected via a low-latency, high-speed communication network. 36 Prepared by Mrs. Rashmi Bhat
- 30. VR System • Hardware: Visual Displays • All the visual displays can either display stereoscopic images, or monoscopic. • Large-screen stationary displays • Use fixed-position screens to fill a relatively large portion of the field-of-view (FOV) • Advantage: • FOV coverage • The reduced amount of hardware worn by users • Disadvantage • include an incomplete view of the virtual world (field-of-regard), cost, and the difficulty of masking the real world if desired 37 Prepared by Mrs. Rashmi Bhat
- 31. VR System • Visual Displays • Head-based Displays (HBD) • Earlier referred as helmet-mounted displays (HMDs) • Heavy headsets with attached screens positioned in front of the wearer's eyes. • Two other types of HBDs • Mechanical arm mounted displays that users pull up to their face • e.g. BOOM (binocular Omni Orientation Monitor) • Smaller screens and weigh less than the original HMDs. 38 Prepared by Mrs. Rashmi Bhat
- 32. VR System • Visual Displays • Head-based Displays (HBD) • Advantage: • User can turn head to see any direction in the world-100% field-of- regard. • Disadvantage • Any latency in VR system is more noticeable to user and may cause nausea or a headeache. 39 Prepared by Mrs. Rashmi Bhat
- 33. VR System • Visual Displays • Desktop VR Displays (Fishtank VR) • Similar to the large-screen displays. • “fishtank VR” is derived from the way one peers into a desktop VR display. • It is a standard computer monitor, often augmented with the ability to display stereographically. • By combining the monitor with the necessary tracking and other input devices and VR software, the scene appears to actually be inside the display • If viewers moves their head left or right, they can see the fish from a different perspective 40 Prepared by Mrs. Rashmi Bhat
- 34. VR System • Visual Displays • Desktop VR Displays (Fishtank VR) • Advantages • It can make use of an existing desktop computer with a few inexpensive additions. • it can be used right at the user’s desk • Disadvantage • very limited field-of-view and very limited field-of-regard • costs to upgrade to a stereoscopic image, along with some input hardware and software to track the user’s movement 41 Prepared by Mrs. Rashmi Bhat
- 35. VR System • Visual Displays • Hand-based VR Displays • A pair of binoculars that contain two small screens instead of the typical lenses. • A screen approximately the size of one’s palm in the hand. • works well as a “magic lens” display, giving the user an altered view of the “reality.” • Modern cellular “smart phones • Advantages: • when a VR experience has a natural interface • user can choose when to look at a handheld display • These displays are not very encumbering • Disadvantage • when the application requires a reasonable amount of FOV. 42 Prepared by Mrs. Rashmi Bhat
- 36. VR System • Aural Displays • Aural image cannot be presented stereophonically. • Monophonic channel of sound can provide a deeply immersive experience. • Problem with stereophonic sound display • it is preproduced (prerendered) to seem as though particular sounds come from particular locations • Spatialization • Sounds that must appear to emanate from a particular location need to be processed to create this effect, this processing is referred to as spatialization. • Aural/Sound Display devices • Loudspeakers (stationary paradigm) • Headphones (head-based display paradigm) 43 Prepared by Mrs. Rashmi Bhat
- 37. VR System • Aural Displays • Advantage: • Loudspeakers can be more easily heard by a group of participants • headphones are generally easier to use when producing spatialized sounds • Disadvantage • When using headphones, if an excessive signal is presented, it will be very close to the listener’s ears 44 Prepared by Mrs. Rashmi Bhat
- 38. VR System • Haptic Displays • Relate to the sense of touch • Two components of haptic displays • “tactile” (input through the skin) • e.g. sensing temperature of hot water • “proprioceptic” (input through the muscular and skeletal systems) • e.g. Sensing how much effort is required to lift a box • Haptic displays can be • “world-grounded” (stationary) • “self-grounded” (body-based) 45 Prepared by Mrs. Rashmi Bhat
- 39. VR System • Haptic Displays • World-grounded displays • Those that have a base attached to the ceiling or that sit on the desktop or are affixed in some way to some object in the real world. • the user holds the end of an arm with multiple linkages leading back to the base. 46 Prepared by Mrs. Rashmi Bhat
- 40. VR System • Haptic Displays • Self-grounded displays • those that are somehow worn by the user. • e.g. glove fitted with some form of tactile display • Force display devices can also be self- grounded, a display that resists the movement of the user’s arm relative to their shoulder. 47 Prepared by Mrs. Rashmi Bhat
- 41. VR System • Other Sensory Displays • The vestibular sense (the sense of balance) • Olfactory display (smell) • computer-controlled display of gustation (taste) virtually nonexistence • most common form of vestibular display is the “motion platform.” • Another style of vestibular display is the bladder-equipped chair. • e.g. VR Chair 48 Prepared by Mrs. Rashmi Bhat
- 42. VR System • Input Devices and User Tracking • Virtual reality systems must track at least some subset of users’ bodies. • Two types of inputs • Cognitive inputs: events specifically triggered by the user • User monitoring: tracking the body movements of the user • Position Sensor • Includes electromagnetic, mechanical, optical, ultrasonic, inertial/gyroscopic, and neural/muscular devices. • Factors: accuracy and precision, interfering media and encumbrance • Props and platforms used to give cognitive inputs • A prop is any physical object that is not part of the scenery and can be manipulated by the actors. 49 Prepared by Mrs. Rashmi Bhat
- 43. VR System • Input Devices and User Tracking • Props and Platform • Are physical places where active input sensors are placed. • Platform is a means of user input to the virtual world Virtual Voyage 50 Prepared by Mrs. Rashmi Bhat
- 44. VR System • Software • Laws of Nature - Simulation code • Programmed laws of nature that govern the behaviors and interactions carried out by the objects in the world. • Only interaction possible is changing the user’s viewpoint relative to the objects in the world. • Advanced simulations can have global behaviors such as gravity, plus individual rules that apply only to specific objects. • It is possible to give objects fantastic behaviors. 51 Prepared by Mrs. Rashmi Bhat
- 45. VR System • Software • Rendering libraries • Convert the form of the world from the internal computer database to what the user experiences. • Must include the appropriate rendering algorithms for whatever sense is to be portrayed. • Include features to render the basic elements of a “scene” along with features to enrich the display. • VR Libraries • Acquire the necessary information about the participant. • Must operate in “real time.” • Include the ability to perform multiple tasks at once. 52 Prepared by Mrs. Rashmi Bhat
- 46. VR System • Software • Ancillary libraries • Modeling software • Sound editing software • Image processing software • User interface libraries 53 Prepared by Mrs. Rashmi Bhat
- 47. Representation • VR experience may have represented • With high degree of accuracy or • With disregard to the structures and limitations extant in the real world and create surreal or fantastic worlds with never- seen-before objects, behaviors, and beings. • A mapping must be made between concepts in the virtual world, and the stimuli that will be presented to the user’s various sensory organs. • The choice of representations is limited to the kinds of transducers available in the system • Within the modes of presentation, tradeoffs exist regarding fidelity versus cost and performance issues. • User's avatar 54 Prepared by Mrs. Rashmi Bhat
- 48. User Interaction Interaction Techniques • Direct Interaction • Best mimics methods of manipulating the real world. • e.g. Moving an object. • Physical Interaction • Input to the virtual world through input devices that the user actually touches. • e.g. Interaction through handheld wand, steering wheel etc. • Virtual Interaction • The “devices” with which one interacts are a part of the virtual world itself. • e.g. virtual button • Rely on physical or direct interactions to activate the virtual device 55 Prepared by Mrs. Rashmi Bhat
- 49. User Interaction Interaction Techniques • Agent Interaction • Communicating with a computer entity (the agent), one lets their desires be known, and expects the system to comply. • e.g. travel through a solar system world, one might say the name of a planet and be taken into orbit around the specified celestial object. Making Selections • Selecting an object on which to act, or to select a direction in which to go. • Pointing with a finger, gazing with the eyes, or facing with the torso. • Using a joystick or steering wheel • The user makes contact with an item to activate it. 56 Prepared by Mrs. Rashmi Bhat
- 50. User Interaction Manipulating Virtual World • Manipulated elements can be either an object of the virtual world or an attribute of the overall virtual reality system • e.g. throwing a ball or saving current status of VR experience in file. • Way of acting on elements • Mimicking the action of forces on elements • Changing attributes of objects in the world 57 Prepared by Mrs. Rashmi Bhat
- 51. User Interaction • Navigation • Describes how we move from place to place. • Navigation can be divided into two subcomponents: Travel and wayfinding • Travel is the act of controlling one’s movement through the world • Wayfinding is using information about the world to guide the direction and speed of travel. 58 Prepared by Mrs. Rashmi Bhat
- 52. User Interaction • Navigation • Common travel paradigms • Physical locomotion • The ability for participants to move their bodies to change the position of their point of view within the virtual world • Ride-along • The method of travel that gives participants little or no freedom • Tow-rope • The user is being pulled along a predetermined path , but with the ability to move off the centerline of the path for a small distance. • Fly-through • A generic term for methods that give the user almost complete freedom of control, in any direction. • Walkthrough: participants’ movements are constrained to follow the terrain 59 Prepared by Mrs. Rashmi Bhat
- 53. User Interaction • Navigation • Common travel paradigms • Pilot-through • The form of travel in which users controls their movements by using controls that mimic some form of vehicle in which they are riding. • Move-the-world • Users “grab” the world and can bring it nearer, or move or orient it in any way by repositioning their hand. • Scale-the-world • Reducing the scale of the world, making a small movement, and then scaling the world back to its original size. 60 Prepared by Mrs. Rashmi Bhat
- 54. User Interaction • Navigation • Common travel paradigms • Put-me-here • A basic method that simply takes the user to some specified position. • Orbital viewing • The world seems to orbit about users depending on which direction they look. • Constrained travel helps users find their way around • Wayfinding aids include • The provision of maps, • Paths in the world to follow, • Obvious landmarks by which to site one, • Virtual compasses. 61 Prepared by Mrs. Rashmi Bhat
- 55. Conclusion History of VR Background of VR Terminologies associated with the VR Technologies VR Applications 62 Prepared by Mrs. Rashmi Bhat