1. Introduction to VR
Virtual Reality (English name: Virtual Reality, abbreviated as VR), also known as the spiritual realm of technology, is a new practical technology developed in the 20th century. Virtual reality technology includes computer, electronic information, simulation technology in one, its basic realization is a computer simulation of virtual environments so as to give people a sense of environmental immersion.
With the continuous development of social productivity and science and technology, the demand for VR technology in all walks of life has become increasingly strong, and VR technology has also made great progress, and gradually become a new field of science and technology.
Virtual reality technology (VR) mainly includes simulated environment, perception, natural skills and sensing devices. The simulated environment is a computer-generated, real-time dynamic three-dimensional stereo realistic image. Perception means that an ideal VR should have all the perceptions that a human being has. In addition to the visual perception generated by computer graphics technology, there are also perceptions such as hearing, touch, force, and motion. Natural skills refer to human head rotation, eye, hand gestures, or other human behavioral actions, which are processed by a computer that processes data appropriate to the participant's actions and responds to the user's inputs in real time and feeds back to each of the user's five senses.
2. History of development (4 stages)
(1) Stage 1: The simulation with sound and shape dynamics is the stage that implies the idea of virtual reality
In 1929, Edward Link designed a simulator used for training pilots; in 1956, Morton Heilig developed a multi-channel simulation and experience system. Sensorama
(2) Stage 2: The Emerging Stage
In 1965, Ivan Sutherland published the paper "UltimateDisplay"; in 1968, Ivan Sutherland In 1968, Ivan Sutherland successfully developed a helmet-mounted stereoscopic display (HMD) with a tracker; in 1972, Nolan Bushell developed Pong, the first interactive video game.
(3) Stage 3: The emergence of the concept of virtual reality and the initial formation of the theory stage
In 1977, Dan Sandin et al. developed the Data Glove; in 1984, NASA AMES Research Center developed the Data Glove. In 1984, NASA AMES Research Center developed a visual display of the virtual environment for Mars exploration; in 1984, VPL first proposed the concept of "virtual reality"; in 1987, Jim Humphries designed the earliest prototype of the binocular omnidirectional monitor (BOOM).
(4) Stage 4: further improvement and application of virtual reality theory
Since the 21st century, VR technology has been developing at a high speed, and the software development system has been continuously improved, with representative ones such as MultiGen Vega, Open Scene Graph, and Virtools, etc.
3.Characteristics
(1) Multi-perception: refers to the fact that in addition to the visual perception that general computers have, there is also auditory perception, tactile perception, motion perception, and even taste, smell, perception and so on. The ideal virtual reality should have all the perceptual functions that people have.
(2) Sense of existence: refers to the degree of realism that the user feels as the protagonist exists in the simulation environment. Ideal simulation environment should reach a level that makes it difficult for the user to distinguish the real from the fake
(3) Interactivity: refers to the degree to which the user can manipulate the objects in the simulation environment and the degree to which the user receives feedback from the environment in a natural way.
(4) Autonomy: the degree to which objects in a virtual environment act according to real-world physical laws of motion
4. Key Technologies
1.1 Computer Graphics Technology
The technology of generating, displaying, and drawing graphics with computers is known as computer graphics technology. Graphics in computers are also represented in the form of data, and to display the graphics or draw and print them, the data must be converted into lines. Computer graphics technology not only can quickly, accurately, standardize the production of a large number of mechanical drawings, architectural drawings, circuit diagrams and geographic maps, etc., to become an important element of computer-aided design, but also can produce motion graphics and three-dimensional graphics, so that the original drawing can not be done to achieve things.
2. Stereoscopic display technology
Stereoscopic display is a realization of virtual reality. Stereoscopic display mainly has the following ways: two-color glasses, active stereoscopic display, passive synchronous stereoscopic projection equipment, stereoscopic display, true three-dimensional stereoscopic display, other more advanced equipment.
3. Visual tracking refers to detecting, extracting, identifying and tracking the motion target in the image sequence, obtaining the motion parameters of the motion target, such as position, speed, acceleration and motion trajectory, etc., so as to carry out the next step of processing and analysis, and to realize the behavioral understanding of the motion target in order to complete the higher level of the detection task.
4. Speech recognition is a cross-discipline. In the last two decades, speech recognition technology has made significant progress and is beginning to move from the laboratory to the market. It is expected that in the next 10 years, speech recognition technology will enter various fields such as industry, home appliances, communications, automotive electronics, medical, home services, consumer electronics. The application of speech recognition dictation machines in a number of fields was named by the U.S. press as one of the ten major events in computer development in 1997. Many experts believe that speech recognition technology is one of the ten most important technological developments in the field of information technology between 2000 and 2010. The fields involved in speech recognition technology include: signal processing, pattern recognition, probability and information theory, vocal and auditory mechanisms, artificial intelligence, and so on.
5. Auditory, Force and Tactile Perception Technology In 2012, many technology companies are researching natural input methods for computers, such as eyeballs, gestures and voice to realize control. Intel wants to develop a unified solution that brings these new technologies together. Intel calls such a technology "perceptual computing".
5. Technical characteristics:
(1) Interactivity of VR
Interactivity of VR refers to the degree to which the user can manipulate objects in virtual reality and the degree to which the user receives feedback naturally from virtual reality, including in real time. It is generated mainly with the help of specialized devices (e.g., operating grips, data gloves, etc.) to manipulate objects in virtual reality in a natural way, such as gestures, body posture, speech, and other skills, as if they were in the real world.
(2) Immersion of VR
The immersion of VR refers to the degree of realism in which the user empathizes with the existence of being the protagonist in virtual reality, which is the most important feature of VR technology. The main aspects of image immersion include perceptibility, autonomy, depth information in 3D graphics, the field of view of the screen, the temporal or spatial response to achieve tracking, and the degree of constraints of the interaction device, among others.
(3) Imagination of VR
The imagination of VR refers to the ability of the user to imagine the future progress of the system as it changes in its operating state in the virtual reality world based on the multiple information acquired and their own behavior in the system through logical judgment, reasoning, and associations and other thought processes. The appropriate application of the object coupled with the creativity and imagination of virtual reality can significantly improve productivity, reduce labor intensity, and improve the quality of product development.