What Is virtual reality?
Virtual reality can be defined as an upcoming technology that makes users feel in a Virtual Environment (VE) by using computer hardware and software. It was originally conceived as a digitally created space which humans could access by donning special computer equipment. It enables people to deal with information more easily. VR provides a different way to see and experience information, one that is dynamic and immediate. For example, in a computer game, user’s joystick motions are tracked and the objects in the game are moved according to the joystick movements. In the same way a simulated, three-dimensional world is created around the user in which he/she could interact with objects, people, and environments. Typically, three-dimensional life-sized images with support of audio devices are presented around the user and the perspective is modified in accordance with the user input (generally head or eye movements). Many devices along with the computers are used to create a virtual environment.
To enter in a VE, a user wear special gloves, earphones, and goggles, all of which send their output to the computer systems. The virtual environments are intended to replace the real world environment with the digital one and the human senses are immersed in the VE. Immersion is an experience of losing oneself in the VE and shutting out all cues from the physical world. A Virtual Environment can be created on different extents depending on the computer based platform ranging from a cell phone screen to a desktop monitor or a fully Immersive Virtual Environment (IVE).
The tracking and rendering turns the whole process more immersive and interactive than the traditional media like televisions and video games. The user actions result in immediate and observable impact on the content of virtual environment.
- Following are the main components of a virtual environment:
- The visual displays that immerse the user in the virtual world and block out contradictory sensory impressions from the real world.
- The graphics rendering system that generates the ever changing images at 20 to 30 frames per second.
- A tracking system that continuously informs the position and orientation of the user’s movements. 4.The database construction and maintenance system to build and maintain a detailed and realistic model of the virtual world.
- A sound system that can produce high quality directional sounds and simulated sound fields.
- Devices like tracked gloves with pushbuttons to enable users to specify their interactions with the virtual objects.
How VR works?
A simple example of ‘Counter Strike’ game can give a thought as to how virtual reality works. The software program for the game is the major element which runs with the help of the computer system and the interfaced input output devices. Every Character and environment within the game behaves closely to reality as per the code written for them. The code facilitates characters and environment to interact with the other characters controlled by the input devices. The code is interpreted by the processor which handles the input – output devices accordingly. This is the simplest example of how VR works. The working of more immersive virtual reality environment is quite similar to working of the game besides the fact that a number of advanced input and output devices along with a high performance processor are added to increase the immersion. The processor executes the processes quickly according to the input given by the user and output is presented to the user in a way that user feels itself a part of the environment and its objects.
The 3D visualization component enables the user to see 3D scenarios by using a display methodology like a head mounted device. Typically, the 3D images superimpose the real environment by using one of the display, screen based or projection based. The screen based virtual environment generally uses a high quality display screen in terms of resolution and color, or a head mounted device along with the sound system as output devices. A keyboard, microphone, head tracking sensors, finger trackers, gesture recognition system, a joystick or similar gears are used as input devices. When user moves the gear or joystick, make move of the head, or press any key on the keyboard, the objects of the screen are changes accordingly in a way that user feels if he/she is directly controlling the objects and environments on the screen. A high speed powerful processor processes the inputs. An Application Programming Interface (API) provides the interface to the input devices connected to the system as well as to standard devices like mouse and keyboard. The timings and relationship between input and output devices are so perfect that user feels an immersion with the virtual environment.
The other technique used to create a virtual environment is projection based, which is more immersive than the screen based method. The display images are projected on the multi-screen spaces ranging from two to six screens. A six screens would make a better virtual environment. Both floor and ceiling uses a rear projection while the other four screens yield large surrounding views for both panning actions and looking down. Consequently, objects inside the space could be walked around and virtual entreat to be touched.
Virtual Reality (VR) Categories
Several categories of virtual reality technologies exist, with more likely to emerge as this technology progresses. The various types of virtual reality differ in their levels of immersion and also virtual reality applications and use cases.
Below, we explore a few of the different categories of virtual reality:
- Non-Immersive
Non-immersive simulations are the least immersive implementation of virtual reality technology. In a non-immersive simulation, only a subset of the user’s senses are stimulated, allowing for peripheral awareness of the reality outside the virtual reality simulation. Users enter into these three-dimensional virtual environments through a portal or window by utilizing standard high resolution monitors powered by processing power typically found on conventional desktop workstations.
- Semi-Immersive
Semi-immersive simulations provide a more immersive experience, in which the user is partly but not fully immersed in a virtual environment. Semi-immersive simulations closely resemble and utilize many of the same technologies found in flight simulation. Semi-immersive simulations are powered by high performance graphical computing systems, which are often then coupled with large screen projector systems or multiple television projection systems to properly stimulate the user’s visuals.
- Fully Immersive
Fully-immersive simulations provide the most immersive implementation of virtual reality technology. In a fully-immersive simulation, hardware such as head-mounted displays and motion detecting devices are used to stimulate all of a user’s senses. Fully immersive simulations are able to provide very realistic user experiences by delivering a wide field of view, high resolutions, increased update rates (also called refresh rate), and high levels of contrast into a user’s head-mounted display (HMD).
References
- https://www.engineersgarage.com/articles/virtual-reality-environment
- https://www.realitytechnologies.com/virtual-reality/