How exactly does artificial gravity work?
If you were in a zero-gravity environment (e.g., in earth orbit or in a coasting trajectory en route to Mars), alone in your space suit, you would feel no gravity.
If a big pipe were placed around you in your zero-g environment, you would still feel no gravity. The pipe would have no effect on you at all.
If the pipe were spun with you inside it but not in contact with it, you would still feel no gravity, because you and the pipe would not be interacting. It makes no difference whether the pipe's spin rate is steady or accelerating.
However, if you moved to the spinning pipe's inside surface and grabbed hold of it, you would feel yourself first yanked by whatever you were hanging onto (because after all it is moving relative to you), and then you would feel yourself being pressed against the inside surface of the pipe. This is for the same reason that a rock swinging around in a circle on the end of a string makes the string taut: centripetal force exerted on the rock by the string tension causes the rock to move in a circle instead of fly off at a tangent.
From the above you can see the answer to the third part of your question: If you are floating in zero-g and enter a spinning chamber, you are not attracted to the walls of the chamber. To someone pinned to the wall by centripetal force, watching you enter the chamber, you will a) seem to be rotating, and b) float like Superman.
It works exactly like a merry-go-round. In a merry-go-round you feel an outward force. If you lie down with your head toward the center, you feel an downward force toward your feet. That is exactly what artificial gravity would be like.
1) A spinning object is accelerated. Each point on the merry-go-round or spinning spaceship is accelerated toward the center, making the point travel in a circle. With no acceleration, each point would travel in a straight line at a constant speed.
2) At the center, you would feel no acceleration, no centrifugal force.
3) The farther from the center, the stronger the centrifugal force. It grows smoothly as you move outward.
You could fly over the ship or merry-go-round without feeling the centrifugal force if you are not spinning or flying in circles. You can stand next to a merry-go-round or run by it without feeling a centrifugal force. If you rode a bicycle around the merry-go-round, you would have to lean in because you would be continually turning. You would feel a centrifugal force.
Lots of good answers for the title but not the enumerated questions.
- Must it always be accelerating? (The rate of rotation for it to work?)
The angular rotation can be constant, but even at a constant speed it is still accelerating.
- If no, and even if yes, if one were to place themselves right at the center of this spinning structure, would one feel no gravity?
They would feel no gravity at the center.
- If one were to be moving from a part of the ship with no centripetal rotation and thus 0 gravity to the part with it what would the experience be like transitioning? Would one technically be able to just fly over the entire rotating thing? If you never touched it in the first place?
It would be similar to being lowered down into one of those fast spinning carnival rides (example pictured). Grabbing onto it would be a similarly unpleasant experience.
