Virtual Reality, abbreviated as VR, is a new practical technology developed in the 20th century. Virtual reality technology includes computer, electronic information, simulation technology, and its basic implementation is a computer simulation of virtual environments to give people a sense of environmental immersion. With the continuous development of social productivity and science and technology, the demand for VR technology is growing in all walks of life, and VR technology has made great progress and is gradually becoming a new field of science and technology.
Basic Introduction
Virtual Reality
Virtual reality is an important direction of simulation technology, which is a collection of simulation technology and computer graphics, human-machine interface technology, multimedia technology, sensing technology, network technology, and other technologies. It is a challenging cross-technology frontier discipline and research field. Virtual reality (VR) technology mainly includes simulation environment, perception, natural skills and sensing devices. The simulated environment is a computer-generated, real-time dynamic three-dimensional realistic image. Perception means that the ideal VR should have all the perceptions that a person has. In addition to the visual perception generated by computer graphics technology, there are auditory, tactile, force, motion and other perceptions, and even smell and taste, also known as multi-perception. Natural skills refer to human head rotation, eye, hand gestures, or other human behavioral movements, which are processed by computers to match the participant’s actions and respond to the user’s input in real time and feedback to each of the user’s five senses. Sensing devices are 3D interactive devices
Development History
The history of the evolution of virtual reality technology can be broadly divided into four stages: the simulation of sound and shape dynamics is the first stage (before 1963) that contains the idea of virtual reality as the second stage (1963-1972), the emergence of the concept of virtual reality and the initial formation of theory as the third stage (1973-1989), the further improvement and application of virtual reality theory as the fourth stage (1990-present). 1990 – present).
Features
Multi-sensory
It refers to the fact that in addition to the visual perception that a general computer has, there are auditory perception, tactile perception, motion perception, and even taste, smell, and perception. The ideal virtual reality should have all the perceptual functions that people have.
Presence perception
It refers to the degree of realism that the user feels as a protagonist in the simulation environment. The ideal simulation environment should be so real that it is difficult for the user to distinguish between real and fake.
Interactivity
The degree to which the user can manipulate the objects in the simulation environment and the degree to which the user can get feedback from the environment naturally.
Autonomy
The degree to which objects in a virtual environment act according to the laws of real-world physical motion.
Key Technologies
Virtual reality is a combination of multiple technologies, including real-time 3D computer graphics technology, wide-angle (wide-field) stereoscopic display technology, tracking technology for the observer’s head, eyes, and hands, and haptic/force feedback, stereo sound, network transmission, and voice input and output technologies. These technologies are described separately below.
Real-time 3D computer graphics
In comparison, it is not too difficult to generate graphic images using computer models. With an accurate enough model and enough time, we can generate accurate images of various objects under different lighting conditions, but the key here is real time. In a flight simulation system, for example, the image refresh is quite important, and also the image quality requirements are high, and combined with a very complex virtual environment, the problem becomes quite difficult.
display
When people look at the world around them, they get slightly different images due to the different positions of their two eyes, and these images are fused in their minds to form an overall view of the world around them, a view that includes information about distance and proximity. Of course, distance information can also be obtained by other methods, such as the distance of eye focal length, comparison of object size, etc.
In VR systems, binocular stereo vision plays a big role. The different images seen by the user’s two eyes are produced separately and displayed on different monitors. Some systems use a single monitor, but when the user puts on special glasses, one eye can only see odd frames and the other eye can only see even frames, and the difference between the odd and even frames, which is parallax, creates a sense of stereo.
User (head, eye) tracking: In the artificial environment, each object has a position and pose relative to the system’s coordinate system, and so does the user. The view the user sees is determined by the user’s position and the orientation of the head (eyes).
Virtual reality headgear that tracks head movement: In traditional computer graphics technology, the field of view is changed by mouse or keyboard, and the user’s visual system and motion perception system are separated, whereas by using head tracking to change the perspective of an image, the user’s visual system and motion perception system can be linked to each other and feel more realistic. Another advantage is that the user can not only recognize the environment through binocular stereo vision, but also observe the environment through head movement.
In the user-computer interaction, keyboard and mouse are by far the most commonly used tools, but they are not well suited for three-dimensional space. In three-dimensional space because there are six degrees of freedom, it is difficult for us to find a more intuitive way to map the plane motion of the mouse into arbitrary motion in three-dimensional space. Now, there are already some devices that can provide six degrees of freedom, such as 3Space digitizer and SpaceBall space ball. Some other devices with better performance are data gloves and data suits.
Technical Features
VR art is an emerging and independent art category that came into being with the advent of the “virtual reality era”. The art form that uses artificial intelligence technologies such as virtual reality (VR) and augmented reality (AR) as a medium is called virtual reality art, or VR art for short. The main characteristics of this art form are hypertextuality and interactivity.”
“As a comprehensive embodiment of the frontier of modern technology, VR art is a new form of art language that visualizes and interacts with complex data through a human-computer interface. The important thing that attracts artists is the close interplay between artistic thinking and technological tools and the new cognitive experience generated by the deep penetration of the two. Compared with new media art under traditional window operation, interactivity and extended human-computer dialogue are the keys to VR art presenting its unique advantages. In an overall sense, VR art is an interactive art form based on a new type of human-computer dialogue, whose greatest advantage lies in constructing a dialogue between the work and the participant, and revealing the process of meaning generation through dialogue.
Through the application of VR, AR and other technologies, artists can adopt more natural means of human-computer interaction to control the form of their works, shape a more immersive artistic environment and dreams that cannot be realized in real situations, and give new meanings to the process of creation. For example, interactive installation systems with VR nature can set up interactive channels for viewers to traverse multiple senses and the process of traversing the installation, and artists can facilitate communication and feedback between participants and the work with the smooth cooperation of software and hardware to create good participation and manipulability; they can also perform motion capture through video interfaces and store clips of visitors’ behaviors to maintain participants’ enhanced consciousness as based on simultaneous projection of enhanced effects and reshaped and processed images; through augmented reality and mixed reality, combining the digital world with the real world, viewers can control the projected text through their own movements, such as data gloves that provide force feedback, movable scenes, and 360-degree rotating sphere space not only enhance the immersion of the work, but also allow viewers to enter the interior, manipulate it, observe its process, and even empower the audience to participate in its re-creation.”