1. VIRTUAL REALITY (VR) INTRODUCTION AND BASIC APPLICATIONS الواقع الافتراضي : مقدمة وتطبيقات Dr. Naji Shukri Alzaza Assist. Prof. of Mobile technology Dean of Community Service and Continuing Education University of Palestine, Alzahra City, Gaza, Palestine najishukri@hotmail.com, www.najishukri.wordpress.com

2. VR OUTPUT DEVICES 4

3. Objectives Dr. Naji Shukri Alzaza 3 Students should be able to understand the:  VR visual output display  Desktop Display, Spatially Immersive Display (SID), Head Mounted Display (HMDs), Workbench and Wall  VR auditory display  Sonification of Interface, Sound Effects, Environmental Audio, Spatialized Audio, Speech Generation  VR haptic display  Tactile, Force, Motion Platform

4. VR Output Devices Dr. Naji Shukri Alzaza 4  In VR systems, one goal is to involve as many of the user’s senses.  So displays have been searched for almost all of the senses (visual, auditory, haptic (touch), olfactory (smell) and vestibular (motion).  Current research has ventured into gustatory (taste) display.  This lecture will concentrate on the 3 most common types of displays: VISUAL, AUDITORY and HAPTIC.

5. VR Visual Output Display Dr. Naji Shukri Alzaza 5  Visual display is the indispensable piece of hardware in VR system. Often it reflects the type of VR system.  There are 4 general categories of VR visual displays: Desktop Displays Spatially Immersive Displays (SID) Head Mounted Displays (HMDs) Workbenches and Walls

6. 1. Desktop Displays Dr. Naji Shukri Alzaza 6  The most common VR visual displays – desktop monitor used for Desktop VR.  Sometimes such displays are enhanced by using stereo graphics and stereo glasses to allow better depth perception.  But for the most part, desktop displays are identical to the displays used by all computer users.

7. Dr. Naji Shukri Alzaza 7  To achieve immersiveness a more complex visual display device is needed that allows the VE to appear to surround the user, or that fills the user’s Field of View (FOV) with the computer graphics.  SID approach – to physically surround the user with the display.  Example : CAVE – uses 4 -6 large projection screens in the shape of a cube into which the user can walk. 2. Spatially Immersive Displays

8. Dr. Naji Shukri Alzaza 8  Stereo graphics are projected onto the screens, so that user sees nothing but the VE and their own body.  The CAVE allow multiple viewers unlike some other VR technologies, but only one viewer has the correct perspective view. 2. Spatially Immersive Displays

9. Dr. Naji Shukri Alzaza 9 Inside a CAVE System

10. 2. Spatially Immersive Displays Dr. Naji Shukri Alzaza 10  Another type of SID – Dome / Hemispherical Display, uses only a single curve screen that wraps around the user to provide immersion.  The Hemispherium is an example of this type of display.  It uses a six meter dome mounted vertically. The user sits in front of the dome so that the display fills his entire field of view.  SID often provide excellent sensations of presence and high resolution graphics but can be costly and are usually not fully immersive (except in the case of 6 sided CAVE.)

11. 2. Spatially Immersive Displays Dr. Naji Shukri Alzaza 11 User seated in the flight chair of the Hemispherium

12. 3. Head Mounted Display Dr. Naji Shukri Alzaza 12  HMD was the earliest VR display and represents another method for achieving immersion.  HMDs use 2 small LCD or CRT screens mounted inside a helmet worn on the user’s head.  The HMDs blocks out the user’s view of the physical world so that only the virtual world can be seen. When the HMD is combined with a head tracker, the user can view the VE in any direction simply by turning his head.

13. 3. Head Mounted Display Dr. Naji Shukri Alzaza 13  HMD can be much less costly and more portable than SID and provide complete physical immersion.  However they have a narrow field of view (30-90 degrees horizontally), a low display resolution (typically 640 x 480 or 800 x 600) and can be heavy and cumbersome.

14. 4. Workbench / Wall Dr. Naji Shukri Alzaza 14  Another approach to providing some level of immersion and wide field of view (FOV) is to use a single, flat, very large display surface.  Typically this takes the form of a horizontal screen upon which the user looks down (workbench) or a vertical screen mounted in front of the user (wall).  Most workbench/ wall displays user rear-projected stereo graphics and stereo glasses for the user.  Head tracking is also common although not required.

15. 4. Workbench / Wall Dr. Naji Shukri Alzaza 15  Some display such as Immersive Workbench allows the screen to be rotated to produce a workbench configuration, a wall configuration or anything between.  Workbenches and walls provide only limited immersion, but they do allow multiple users to share the display and afford direct manipulation of the displayed data.

16. Auditory Display Dr. Naji Shukri Alzaza 16  Audio plays a significant role in VEs.  User’s sense of presence may be increased considerably by the use of sounds during navigation and interaction.  Naturalness of audio can be achieved by both the presented audio spectrum (the number of different kinds of sounds used) and the sound locations.  Employing spatial sound allows the participant to become aware of the location and direction of sound.  The audio signals continuously change to reflect the participant’s movements, creating a feeling of space.

17. Auditory Display Dr. Naji Shukri Alzaza 17  Many advanced VR systems use spatial audio, which presents auditory information that sounds as if its source is at a particular location in 3D space.  Audio sub-topics: 1. Sonification (Use of non-speech audio to convey information) 2. Sound Effects (Classic Multimedia, game tool) 3. Spatialized Audio (2 ears allow localization) 4. Environmental Audio (Air Absorbtion, Room acoustics) 5. Speech Generation (Prerecorded words, phonemes and diphones)

18. Auditory Display Dr. Naji Shukri Alzaza 18  Audio Display Devices – PC sound boards – External 3D Processor – External synthesizer, mixer – Stereo Headset – Stereo speakers – Multiple Speakers – Bass Shaker Speaker – Amplifiers

19. Haptic Display Dr. Naji Shukri Alzaza 19 Terminologies  Haptic - Relating to the sense of touch.  Kinaesthetic - Meaning the feeling of motion. Relating to sensations originating in muscles, tendons and joints.  Tactile - Pertaining to the cutaneous sense - the sensation of pressure  Force Feedback - Relating to the mechanical production of information sensed by the human kinesthetic system.

20. Haptic Display Dr. Naji Shukri Alzaza 20  Tactile information is produced by perturbing (disturbing) the skin Pins - either alone or in an array, as in devices for Braille display and typically used for fingertip stimulation. Air jets blow to produce a disturbance. Cushions of air can be inflated or deflated to vary pressure on skin. Electrical stimulation -low levels of current provide a localized tingling sensation.  Typically used in gloves, or for larger body areas.

21. Haptic Display Dr. Naji Shukri Alzaza 21 VITAL (acronym for VibroTActiLe) CyberTouch

22. Haptic Display Dr. Naji Shukri Alzaza 22  Kinesthetic haptic devices are available, either in laboratories or commercially, for a wide range of application areas including:  Desktop Interfaces: Interfaces are developed for desktop application like Virtual Sculpture or Computer Aided Design. They are intended to be used with a workstation and act as a 6 DOF mouse with force feedback.  General Haptic Interfaces / Hi-Fidelity Teleoperation: Interfaces are intended for general purpose haptics and teleoperation applications requiring high precision and sensitivity (like telesurgery).

23. Haptic Display Dr. Naji Shukri Alzaza 23  Scale One Interfaces / Remote Handling : These interfaces are used in workbenches or large scale environments to virtually simulate real manipulation as close as possible to scale one.  Hand exoskeletons: They are intended to allow natural finger interaction. Ease of use and adaptability to general public is of particular importance.  Arm exoskeletons: They are intended to allow natural hand interaction. They can also be used for rehabilitation purposes.

24. Haptic Display Dr. Naji Shukri Alzaza 24  Many types of haptic display in VE.  The most common type is a mechanical linkage device that displays force to the user at a single point, such as the Phantom device.  This device allows users to probe virtual objects with a fingertip or stylus in order to feel the surface. PHANTOM 1.5 High Force / 6DOF

25. Haptic Display Phantom Dr. Naji Shukri Alzaza 25

26. Haptic Display Dr. Naji Shukri Alzaza 26  Exoskeleton allows users to grasp virtual objects and feel the force on all five fingers.  These two types can be combined to allow both grasping and probing. Exoskeleton (left) and combination exoskeleton and mechanical linkage (right) haptic devices

27. Haptic Display Exoskeleton Dr. Naji Shukri Alzaza 27

28. 28 Dr. Naji Shukri Alzaza