Artificial gravity is created, in most cases, by placing a disk made of super-conducting material inside a sealed environment. The disk is suspended within a magnetic field so that it can not touch any portion of its casing, and then spun at extreme velocities (Approximately 130,000 RPM). This creates a gravito-magnetic field that extends outward from the device in a 100 ft radius. For most small craft, one or two generators is usually enough to create approximately 1G (Earth normal) of gravitational force throughout the entire vessel.
It is important to note that the addition of artificial gravity to space-faring vessels, while an important step towards space exploration and colonization, was not the final answer needed to make it more plausible. There are several factors of space travel that must be considered for long-term exposure purposes, gravity being a significant one. Other factors include but are not limited to the following:
Radiation/EM shielding (filtering out those energies present in space which are NOT present in a livable atmosphere)
Radiation and EM field generation (reproducing those energies that ARE present in a livable atmosphere, and necessary for long-term health)
Acceleration/decelaeraion/inertial compensation (in order to keep the human body from turning to paste during sudden maneuvers and alterations in ship velocities)
These gravity generating devices can also be used in fixed/planetary applications in order to increase whatever gravity they have to 1G. In this application they are usually known as “Gravity Levelers” since they are not creating the entire gravity field by themselves, but rather adding to an existing field in order to increase its strength. At present there is no known way of reducing a gravity field in order to make high gravity installations more palatable to the human body.
There is research into other means of creating gravity artificially, using the same principals as the Gravitic super-luminal drive systems, however, creating a field that is dispersed widely enough and consistently enough for practical purposes is proving to be troublesome at present.