I got here late, was googling for / to make a 3Dmodel using existing environmental sections designed for the ISS, placed at a 30 ft radius, NOT coupled to the center/longitudinal section. Running on magnetic rail system so there is minimum drag. Of course there would be some drag buy the magnetic field. I figured two 14 foot sections for the radius. Making some thing between 60 - 90 feet for the diameter. Rotating fiber optic data communications. Solar panels can be on the ring so no need for a power coupling. This is a very interesting conversation because, even at 60+ it may be seen in my life time. A trip to Mars should have some form of gravity for spinal issues. Either the entire ship would rotate during the year and stop rotation near the planet if needed. I can see only looking out the window to be an issue with the rotations. Solar panels can be directed and the angle of attack from the vessel would not matter during the flight. I think it could be done with under 20 units, or made larger if the inflatable units hold up. Kind of like an Avalon inflatable boat, sections open but sealed and separate in cause of an issue. Either 2 , 3, 4 tubes, sections from the center of the craft to the ring.
I can not see a way to have the ring attached to the main ship and rotating while trying to keep a seal 5 meters in diameter. The magnetic coupling to limit drag I can see. But the best result (in my thoughts) is to have a sold connection and the entire ship rotating. I am thinking of printing something for fun but realistic. Comments/ suggestions, appreciated. If a solid connection/ship what issues would one think the crew would have. I can see only if their point of relativity is out the window being an issue, but not looking out the window, I can see ZERO G in the center of the vessel and maybe .25 or .5 G at the outer part of the ring. My sentences may be a little broken, but I think you can get the idea. Using existing units, how can a vessel be made for a 3 year trip? I don't see a space shuttle type of ship, more like something in the show Passengers, but we do not have the skill to do some thing that size. Just to keep the sun exposed side and the non exposed side the same shape would be a huge challenge. But if made from fabric, maybe. What am I missing. Thanks
George