Gravity is essential for human health, especially bone and optic health.
As mankind began to live permanently in space, it became essential to have some sort of gravity, or rather a passive push-down force. However, artificial gravity continued to be alchemist's gold.
Given the need and desire for space exploration, it was inevitable that mankind soon dipped into DNA modification.
In short, by year 9599, weakening bone was no longer an issue for humans in Two Clusters.
For large structures, such as space stations and outposts, gaining gravity was relatively easy as it could spin to create artificial gravity ( Centrifugal force ). It wasn’t perfect but, on a large enough scale, it was adequate enough.
However, for smaller ships such as cruisers, spinning was not an option.
Gravity by definition is basically a passive push-down force, and the easiest way to mimic such a force in a small scale is by using magnetic fields.
It resulted redesign of space uniforms used in vessels. Iron threads were embedded into uniforms and their shoes featured metal bottom coated with thin rubber.
A magnetic field would be active only on floor so that a passive push-down force could be created. The field had to be weak but constant. It had to be weak so that it would not interfere with any electronic systems. It had to be constant to be fake gravity.
Cruiser class and higher vessels had no problem implementing such a feature. Those ships also had spare processing powers to address control of magnetic fields. However, for smaller ships like frigates and shuttles, it was not possible to have a magnetic field, let alone control it. It would also increase production cost of vessels in addition.
In the end, cruiser class vessels and higher had a magnetic field implemented while shuttle and frigates didn't. For frigates, a workaround was steel floors and magnetic boots, a setup that required no additional resources. Space transports also had a magnetic field implemented for passenger comfort.
Two Clusters sets itself in a space age. It was not uncommon for an ordinary person to ride a transport from Moon to Earth or Earth to Venus. Moon to Earth was a 30-minute travel. And Earth to Venus was a two-day travel.
Implementation of a magnetic field to act as gravity resulted a fundamental change in clothing. Since passengers did not get into space suits, it was required by laws to add metal threads into common cloth. Shoes, any shoes including high heel and jogging shoes, had a thin metal plate underneath. None of these were permanent solutions for lack of gravity though. There were simply there to provide some form of extra comfort in zero gravity.
There were miscellaneous issues with zero gravity.
Hygiene also posed issues. Bath was not possible in zero gravity. Shower was possible but it was messy. Workarounds were created for showers to work. Basically, a confined, water sealed, cube was created with a shower system. It'd have a suction drain on each wall to drain floating pallets of water particles.
Another, easier method, was a steam shower which wasn’t always favored by some due to a possibility that dirty/soap steam would enter one’s lungs.
Urine was an issue as well, but a solution was relatively easy by creating a suction toilet similar to those found in air plane of our own time. It'd have a suction effect on all the time to prevent any loose pallets of urine however.
Medical technologies in Two Clusters were advanced enough to cure all other health issues from inhabiting in zero gravity for extensive amount of time.