FullDive

FullDive is the use of technology to fully immerse one's consciousness in virtual reality. Developed by Kayaba Akihiko, it led to the creation of the device called NerveGear. It is the basis of most of the stories in the entire Sword Art Online series.

A NERve Direct Linkage Environment System or NERDLES (ニードルス) is required for a FullDive.

Known VR Consoles

 * Nerve Gear
 * AmuSphere
 * MediCuboid
 * Soul Translator
 * Neuro Linker (Accel World crossover)

NerveGear
The NerveGear (ナーヴギア) was created by Argus. It only has a single interface that covers the player's whole head and face. It completely controls the player's consciousness by redirecting the signals the brain sends to the body and sending its own waves to stimulate the five senses. It has its own battery source, as well as a high frequency electromagnetic microwaves transmitter. NerveGear, when first produced, only puzzles, education related, or environmental type games were brought out. So, Sword Art Online was a major excitement to all gamers. This design trapped 10,000 players during the official launch of Sword Art Online in September 2022. It is the first VR technology that has been mass-produced.

AmuSphere
AmuSphere (アミュスフィア) is the revised version of the NerveGear which was co-developed by RECTO Progress Inc.. The system has been modified to make it safer than its predecessor by changing the microwaves transmitter to a low frequency one and the incorporation of various sensors that continually monitor blood pressure and brain waves which provoke a safety logout feature in case that the person's statuses become abnormal. In addition, the AmuSphere does not completely block out signals from the body, like its predecessor, the NerveGear did, so some players may pay extra for specialized rooms designed to make the experience all the more real.

MediCuboid
The MediCuboid (メディキュボイド) is a 3rd generation FullDive machine developed for use in the medical field, instead of the entertainment industry. The basic design of the machine was provided by Koujiro Rinko, based on the machine that Kayaba used to copy his memories and thoughts onto the Internet. Unlike the 2nd generation devices that only consist of a helmet that connects to the user's brain, the MediCuboid is integrated with a bed, from the head to the spinal cord, rather than just a helmet and it connects not only to the medulla, but to the spinal cord as well. It also possesses a greater processing power, allowing interaction with deeper parts of the brain. All these improvements provide the user with enhanced reflexes and reaction time. However, this machine is only meant to be used for medical purposes, specifically for patients in Terminal Care. The users of the MediCuboid hardly use their own bodies to come back to the real world; instead, they connect to external devices, like cameras and microphones, via the MediCuboid to interact with the real world.

Beyond FullDiving
During Project Alicization, a new technology is hinted at which is called Brain Machine Interface, or BMI for short, where the mind is accelerated to x times the normal, giving the person the ability to perform processing x times faster. The BMI uses a different FullDive technique. It starts with «Soul Translation». Kirito explained that this complexity is of the brain: the synapse is the sole transmitter between neurons, and then goes into a theory: Quantam brain dynamics, which is like the cell frame to support its structure, like a skull. However, it is in a shape of a tube, which has a light particle, or evanescent photon, a quantum. The collection of photons in the computer, is called «Fluctuating Light», shortened to «Fluctlight». The «Soul Translator» translate «Fluctlight», or the words humans understand and write out the information into a form that could be read.

Usage
To use NerveGear and AmuSphere, the player places the game console over the head. Then, the player will lay down in a comfortable position, usually in a bed. Afterwards, the helmet-like console will activate through the initiation words «Link Start» and will begin loading the currently inserted game.

Trivia

 * Though it is not seen or mentioned in the SAO series, the Neuro Linker is a device like the AmuSphere serving the same purpose as a VR device.

Tecnología de inmersión total FullDive Полное Погружение