This week at the Paris Air Show, Malloy Aeronautics revealed a deal with the U.S. Department of Defense to develop its Hoverbike. The Hoverbike, which is similar to a quadcopter, uses four standard helicopter style rotors, and would operate in a new class of Tactical Reconnaissance Vehicles."
I've been following a private, home built, man carrying quad copter design in progress. The guy is doing a lot of testing, and the electronic parts is done so well in toys, that THAT part is easy. He's using IC engines, and the response time is the issue. Batteries won't allow the range to get to the store.
There's a lot of interest in the Zero and other electric motorcycles in light aviation. An old flying buddy of mine, Eric Raymond, is now in Slovenia building, and flying, some amazing machines.
Human carrying multi-copters are a bit more difficult.
For example, these guys made the first man carrying multi copter flight. Not very high, and you have to love the genius behind the landing gear. ( durable, light, cheap... three words not often found together in aviation ) The big, pretty version has flown RC inside, but I haven't heard of anyone buzzing around Stuttgart with one.
I suspect the U.S. home builders will be at the leading edge in this, despite the vast sums of money thrown at it by governments.
BTW, the "artists" rendering of the "hoverbike" shows a suicidal Cuisinart, with no engines, batteries, or possibility of functional reality. The real deal will not be as pretty, but you might live in a hard landing. Or maybe not.
Remote control, and a light dummy, but at least partly working.
Need a cvt for each engine to get response time quick enough, that also allows single engine power. Alternate might be variable pitch blades which should be even faster than the cvt.
CVT would be slow to control, I'd think. Multicopters change speed on the motors to keep upright. Variable pitch blades could work, or perhaps computer controlled fuel injection?
The Former Soviet States are also a hotbed of aviation design & manufacture. They may be New Russian States soon, and there have been some companies caught up in the war that are in limbo or gone.
"variable pitch blades which should be even faster than the cvt"
Constant RPM with variable pitch props might be an answer. The advantages are that you can get near real time lift increases and decreases and also higher efficiency, since you can tune the engine to make power in a very narrow band.