1 introduction. VR（Virtual Reality）
Virtual Reality technology (English name: virtual reality, abbreviated as VR), also known as spiritual technology, is a brand-new practical technology developed in the 20th century. Virtual reality technology includes computer, electronic information and simulation technology, and its basic realization mode is computer simulation of virtual environment, thus giving people a sense of environmental immersion.
With the continuous development of social productive forces and science and technology, there is an increasing demand for VR technology in all walks of life. VR technology has also made great progress and gradually become a new field of science and technology.
Virtual reality technology mainly includes simulated environment, perception, natural skills and sensing equipment. The simulation environment is a computer-generated real-time dynamic three-dimensional realistic image. Perception means that the ideal VR should have the perception that everyone has. In addition to the visual perception produced by computer graphics technology, there are also hearing, touch, force and movement. Natural skills refer to people's head rotation, eyes, gestures or other human actions. The computer processes the data adapted to the actions of the participants, responds to the user's input in real time, and feeds it back to the user's five senses respectively.
2. Development history (4 stages)
(1) the first stage: the simulation of sound and shape dynamics is a stage that contains the idea of virtual reality.
1929, Edward Link designed a simulator for training pilots. 1956, Morton Heilig developed the multi-channel analog experience system Sensorama.
(2) The second stage: the budding stage
1965, ivan sutherland published a paper "ultimate display"; 1968, Ivan Su Zelan successfully developed a helmet-mounted stereoscopic display (HMD) with a tracker. 1972, Nolan Bscher invented the first interactive video game table tennis.
(3) The third stage: the emergence of the concept of virtual reality and the initial formation of the theory.
1977, Dan Sundin and others developed data gloves; In 1984, Ames Research Center of NASA developed a virtual environment visual display for Mars exploration. 1984, VPL company first put forward the concept of "virtual reality"; 1987, JimHumphries designed the earliest binocular omni-directional monitor (BOOM) prototype.
(4) The fourth stage: the further improvement and application of virtual reality theory.
Since the 20th century, VR technology has developed rapidly, and software development systems have been continuously improved, such as MultiGen Vega, Open Scene Graph, Virtools and so on.
3. Characteristics
(1) Multi-perception: refers to auditory perception, tactile perception, motor perception, and even taste, smell and perception. The ideal virtual reality should have the perceptual function that everyone has.
(2) Presence: refers to the real degree that the user feels as the protagonist in the simulation environment. The ideal simulation environment should reach the point where it is difficult for users to distinguish between true and false.
(3) Interactivity: refers to the user's operability of objects in the simulated environment and the naturalness of getting feedback from the environment.
(4) Autonomy: refers to the degree to which objects in the virtual environment act according to the laws of physical movement in the real world.
4. Key technologies
1. 1 computer graphics technology
The technology of generating, displaying and drawing graphics by computer is called computer graphics technology. Graphics in computers are also represented in the form of data. To display graphics or draw and print, data must be converted into lines. Computer graphics technology can not only make a large number of mechanical drawings, architectural drawings, circuit diagrams and geographical maps quickly, accurately and normatively, and become an important part of computer-aided design, but also make moving graphics and three-dimensional graphics, so that things that the original drawing can not do can be realized.
2. Stereo display technology
Stereo display is a way to realize virtual reality. Stereo display mainly has the following ways: two-color glasses, active stereo display, passive synchronous stereo projection equipment, stereo display, true three-dimensional stereo display, and other more advanced equipment.
3. Visual tracking refers to detecting, extracting, identifying and tracking the moving target in the image sequence, and obtaining the moving parameters such as the position, speed, acceleration and trajectory of the moving target, so as to carry out the next processing and analysis, realize the behavior understanding of the moving target and complete the higher-level detection task.
4. Speech recognition is an interdisciplinary subject. In the past twenty years, speech recognition technology has made remarkable progress, and began to move from laboratory to market. It is predicted that in the next 10 year, speech recognition technology will enter various fields such as industry, home appliances, communication, automotive electronics, medical care, home service and consumer electronics. The application of speech recognition dictation machine in some fields was rated as one of the top ten events of computer development in 1997 by the American press. Many experts believe that speech recognition technology is one of the top ten important technology development technologies in the information technology field from 2000 to 20 10. The fields involved in speech recognition technology include: signal processing, pattern recognition, probability theory and information theory, vocal mechanism and auditory mechanism, artificial intelligence and so on.
5. Hearing, dynamics and tactile perception technology 20 12, 1 year, many technology companies are studying the natural input methods of computers, such as eyeballs, gestures and voices to achieve control. Intel hopes to develop a unified solution that combines these new technologies. Intel calls this technology "perceptual computing".
5. Technical features:
Interaction of (1)VR
The interactivity of VR refers to the degree to which users can manipulate objects in virtual reality and the natural degree to get feedback from virtual reality, including real-time. Mainly with the help of special equipment (such as operating handle, data gloves, etc. ), objects in virtual reality are operated in a natural way, such as gestures, body posture, language and other skills, just like in the real world.
2) Immersion of virtual reality
The immersion of VR refers to the real degree of the user's empathy with the protagonist in virtual reality, which is the most important feature of VR technology. Image immersion mainly includes perception, autonomy, depth information in three-dimensional graphics, visual field of the picture, time or spatial response to tracking, and constraint degree of interactive equipment.
Imagination of virtual reality
The imagination of VR refers to the user's ability to imagine the future progress of the system with the change of the running state of the system through the thinking process of logical judgment, reasoning and association according to the obtained information and his own behavior in the virtual reality world. Adding the creativity and imagination of virtual reality to suitable application objects can greatly improve production efficiency, reduce labor intensity and improve product development quality.