The system duly accelerates, gaining angular momentum:
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Believe it or not, this is actually just another form of kiiking, in essence:
• the weight being lowered tangentially / circumferentially is spending more time subject to the gravitating condition (ie. being accelerated or decelerated by gravity), compared to the one rising in the predominantly-radial plane (which is still receiving some angular lift too), and this up vs down 'time-spent-gravitating' asymmetry is directly proportionate to the yield of unidirectional momentum so gained from gravity
Thus the momentum gained from simple, Classic OB - albeit at energy unity, here - was always the same essential principle - the same momentum-gain mechanism - as kiiking.
Yet look closer at the above demonstration, and you'll notice something is a bit different here:
• MoI is constant! We have two equal masses changing radius, yet MoI remains pegged at 2 kg-m²-rad/s!
• In other words, zero work is being done against CF force!
This has been accomplished by carefully controlling the relative radial speeds of the weights - they have to slide in and out at different speeds relative to one another, and that ideal speed variation follows a curve; we can either vary both radial speeds to track that curve, or else hold one constant whilst varying the other. In the example above, 'MoI' is being used as reactive feedback to control this radial speed variation.
The net result is, as you see, continual OB / 360° kiiking, yet without doing any work against CF - let alone more with rising RPM. We've just done away with the whole CF game entirely..
So whereas a standard kiiking mechanism gains momentum from gravity by performing work against CF force - the rotKE increase is equal to the net work done against CF force, with zero net work done against gravity - here we've flipped the input workload over to gravity-only; the rotKE rise is now equal to the net work done against gravity, with zero net work done against CF force.
Instead, now the only input energy is GPE, and obviously, GPE is speed-invariant - it costs the same input energy per cycle regardless of RPM.. or, to put it another way, the actuator's workload is in an inertial FoR, so can diverge, in principle, if the momentum yields could be held up; under such conditions, a given actuator input F*d / GPE would cause a greater rise in output rotKE..
So speed-invariant input energy per cycle isn't a goal unto itself; the whole point is the progressing energy cost of momentum, remember, so fixing the input energy is only really productive if the momentum yield is also fixed - or at least, not reducing at a rate that matches ½mV²..
..yet here, unfortunately, that's exactly what's happening: as previously noted, per-cycle momentum yields are diminishing as RPM's climb (not currently plotting momentum but it's just MoI times RPM, so implicit already)..
..the ratio of the asymmetry is constant and RPM-invariant, however the absolute magnitude of the momentum yield is still decreasing along with the net 'exposure time' to gravity per cycle. These diminishing returns perfectly track unity; the rise in rotKE is precisely equal to the work done against gravity. GMH = rotKE.
So the next objective is to try one or more of these systems in orbiting axes; as before, torquing the central axis against them using motors, and so raising 'orbital' angular momentum of one sign, and equal axial angular momentum of the other.
Then simply employ the above OB cycle in reverse, sinking the counter-momentum to gravity. Brake the rotors back together after each cycle, so the orbiting motors always restart each cycle from the bottom of the V² ladder, hence paying only ½ J / kg-m²-rad/s regardless of current RPM. No net work is done against axial CF, no net work was ever done against orbital CF previously, so touch wood, this could be the cheapest momentum possible - paying only ½ J per kg-m²-rad/s..
The amount of counter-momentum that can be sunk to gravity per-cycle - and thus the resulting momentum yield - will probably still decline with rising RPM; the main difference will be that the principle source of torque becomes the orbiting motors, rather than OB torque, which instead will only be sinking counter-momentum.
So i'm thinking, as before, to try maybe a pair of these mounted to a larger wheel, with gravity enabled.. plot input energy in terms of motor torque * angle and actuator F*d, and compare their sum to the output energy in terms of net KE..
The broad picture's akin to spinning up a turntable by standing on its edge and counter-spinning a smaller rotor in your hands, and then dumping that counter-momentum to gravity and repeating. Simple concept, but how do the various constraints on its efficiency pan out?
ETA: sim attached