•What is Virtual Reality?•Why we need Virtual Reality?•Virtual reality systems•Virtual Reality hardware•Virtual Reality developing tools•The Future of Virtual Reality

What is Virtual Reality ?•Virtual reality is, plainly

speaking, seeing an imaginary world, rather than the real one. Seeing, hearing, smelling, testing, feeling. The imaginary world is a simulation running in a computer. The sense data is fed by some system to our brain.

•A medium composed of interactive computer simulations giving users the feeling of being present in the simulations

Why Virtual Reality is needed?Operations in dangerous

environmentsThere are still many examples of people working in dangerous or hardship environments that could benefit from the use of VR-mediated teleportation.

Workers in radioactive, space, or toxic environments could be relocated to the safety of a VR environment where they could 'handle' any hazardous materials without any real danger using teleoperation or telepresence.

Why Virtual Reality is needed? Scientific Visualization

Scientific Visualization provides the researcher with immediate graphical feedback during the course of the computations and gives him/her the ability to 'steer' the solution process.

Application at NASA Ames Research Center is the Virtual Planetary Exploration. It helps planetary geologists to remotely analyze the surface of a planet. They use VR techniques to roam planetary terrains.

NASA VR Mars navigation simulation

Geologists remote analyzing the surface of a planet at NASA

Why Virtual Reality is needed? Medicine

Until now experimental research and education in medicine was mainly based on dissection and study of plastic models. Computerized 3D human models provide a new approach to research and education in medicine. Experimenting medical research with virtual patients will be a reality.

We will be able to create not only realistic looking virtual patients, but also histological and bone structures. With the simulation of the entire physiology of the human body,

Real 3D Ultrasound Experiment

Exposure Therapy For Acrophobia

Why Virtual Reality is needed?Education and training

The most common example is the flight simulator. This type of simulator has shown the benefits of simulation environments for training. They have lower operating costs and are safer to use than real aircraft.

They also allow the simulation of dangerous scenarios not allowable with real aircraft.

Virtual Reality SystemsVR Systems can be divided into three groups

non-immersive systems (like workstations)See information about the real world, presented via computer - location based services, GIS . hybrid systems (graphics on top of real world) also called: Augmented reality systems Stay in real world, but see simulated objects

immersive systems (like HMD or CAVE) See simulated world and "be" in that simulated world

Non-immersive systems

Large display, but doesn’t surroundthe user.

Augmented realityStay in real world, but see simulated objects

More Augmented RealityStay in real world, but

Augmented Reality can be used for training as well as for assembly purpose

Immersive systems (CAVE)See simulated world and "be" in that simulated world

• The CAVE (Cave Automatic Virtual Environment) provides the illusion of immersion by projecting stereo images on the walls and floor of a room-sized cube.

• Several persons wearing lightweight stereo glasses can enter and walk freely inside the CAVE.

CAVE PicturesSee simulated world and "be" in that simulated world

Illusions of immersion

Hardware used in VRInput devices:

A variety of input devices allow the user to navigate through a virtual environment and to interact with virtual objects. Directional sound, tactile and force feedback devices, voice recognition and other technologies are being employed to enrich the immersive experience and to create more "sensualized" interfaces.

Input Devices (The Data Glove)

the sensors measure the bending angles of the joints of the thumb and the lower and middle knuckles of the others fingers, Attached to the back is a Polhemus sensor to measure orientation and position of the gloved hand. Thisinformation, along with the ten flex angles for the knuckles is transmitted through a serial communication line to the host computer.

Input Devices (3D Mouse and Space Ball)

The Logitech 3D mouse Figure is based on a ultrasonic position reference array, which is a tripod consisting of three ultrasonic speakers set in a triangular position, emits ultrasonic sound signals from each of the three transmitters. These are used to track the receiver position, orientation and movement. It provides proportional output in all 6 degrees of freedom: X, Y, Z, Pitch, Yaw, and Roll..

Input Devices (Motion Trackers)

The Motion Tracking system is based on magnetic sensors which are attached to the user. Most common are sensors measuring the intensity of a magnetic field generated at a reference point. The motion of the different segments is tracked using magnetic sensors . These sensors return raw data (e.g. positions and orientations) expressed in a single frame system..

Other Input DevicesMIDI keyboardA MIDI keyboard controller has 88 keys, any of which can be struck within a fraction of second. Each key transmits velocity of keystroke as well as pressure after the key is pressed.

Real-time video inputSIRIUS® Video card from Silicon Graphics. With SIRIUS®, images are digitized at a frequency of 25 Hz (PAL) or 30 Hz (NTSC) and may be analyzed by the VR program.

Real-time audio inputSpeech synthesis facilities are of clear utility in a VR environment especially for command feedback. Although speech synthesis software is available even at the personal computer level, some improvement is still needed, particularly in the quality of speech.

Output DevicesHead-mounted displays (HMDs)

The head-mounted display (HMD) was the first device providing its wearer with an immersive experience. A typical HMD houses two miniature display screens and an optical system that channels the images from the screens to the eyes, thereby, presenting a stereo view of a virtual world. As a result, the viewer can look around and walk through the surrounding virtual environment.

BOOM (Binocular Omni-Orientation Monitor)

The BOOM (Binocular Omni-Orientation Monitor) from Fake space is a head-coupled stereoscopic display device. Screens and optical system are housed in a box that is attached to a multi-link arm. The user looks into the box through two holes, sees the virtual world, and can guide the box to any position within the operational volume of the device.

Virtual Reality developing tools(Virtual Reality Modeling Language)In addition to HTML (Hypertext Markup Language), that has become a standard authoring tool for the creation of home pages, VRML provides three-dimensional worlds with integrated hyperlinks on the Web..

The viewing of VRML models via a VRML plug-in for Web browsers is usually done on a graphics monitor under mouse-control and, therefore, not fully immersive.

However the syntax and data structure of VRML provide an excellent tool for the modeling of three-dimensional worlds that are functional and interactive and that can, ultimately, be transferred into fully immersive viewing systems.

The current version VRML 2.0 has become an international ISO/IEC standard under the name VRML97.

The Future of Virtual RealityVirtual Reality is a growing industryPC and specialized hardware are getting better, faster and cheaper because of development in VR.Maybe 3D user interfaces will replace the windows based ones?Huge demand for VRML programmers in near future.Revolution in gaming industries