..minor update:
• nothing in the sim has changed - like i say, it was designed with precision - all the main meters are using all the same equations, and all i've done in debugging is copy/blow up one of the MoI-controlling actuator P*t integrals, alongside an added F*d integral for the same workload; then tuning freq / integration steps per frame and the FFB strength, until the error between those two sample metrics is minimal.
Making a
combined F*d integral for all actuators would seem dodgy, since they all have potentially different lengths and excursions, and taking 20 different F*d integrals - one for each actuator, at 32k data points per pop - is so much work as to begin defeating the purpose of simming in the first place.. So nailing the combined P*t integrals to within an acceptable error margin is the practical solution.
Results so far (still using the previous 'max freq / HQ' sim) look like this:
i-s/f = 10
FFB = 1e5
F*d = 933.1995241 J
P*t = 932.7370251 J
diff = -0.462499 J
i-s/f = 1
FFB = 1e4
F*d = 915.9918219 J
P*t = 915.1067633 J
diff = 0.8850586 J
i-s/f = 1,000
FFB = 2.5e5
F*d = 946.9764142 J
P*t = 946.7414876 J
diff = 0.2349266 J
i-s/f = 10,000
FFB = 2.5e5
F*d = 950.5879602 J
P*t = 950.3541813 J
diff = 0.2337789 J
..so it looks like v. high i-s/f's are redundant - gonna settle at a value of 100 since there's little difference between 10 and 10,000; cranking the FFB multi as high as it'll go without spazzing out seems to minimise the error, and ultimately we only need to know reliably whatever the error margin
is - be it 2 mJ or whatever - to proceed with some degree of confidence..
.. i say 'proceed' - still ain't seen any gain potential yet tho, so all i have in mind is speculative 'spin & brake' regimes (ie. lock the weight axes as they descend, then unlock 'em when rising, or
whatevs) and just measure the energies looking out for anything interesting..
..and yet in all this time spent debugging i've pretty much already run those tests in me head, and like i say, not seen anything interesting - obviously, it can't get wider forever, and even 1 full turn is way too much, so the actuators need to reverse at some point, and there needs to be a collision in between... uh.. but how to plot out a KE gain from an N3 break that way? Or a PE gain?
So while chewing over that central question, i've come back to a thought experiment that's just a slight variation on a previous rig i keep mentioning in all these threads, wherein counter-torque from a motor is cancelled by inertial torque from a vMoI:
I just figured another way of looking at this interaction.
It's the same general concept Fletch was playing with a few years back, namely, converting (somehow) a given quantity of momentum into a higher-energy distribution of mass and velocity, for (somehow) less than the resulting KE gain..
..the point is this:
• a 'rotor' and 'stator' begin in equal co-rotation; so, stationary with respect to each other, and at equal speed relative to the observer FoR
• a motor placed between them is activated, thus attempting to further accelerate the rotor, whilst decelerating the 'stator' to absolute stationary
• this would conserve the net momentum, simply migrating the initial momentum on the 'stator' over to the rotor
• however, the stator is also a 'vMoI' - as the motor fires, the stator mass is pulled inwards, generating a positive inertial torque that counteracts the motor's counter-torque, perfectly matching it..
• ..as a result, the momentum gained by the rotor has
still come at the expense of that of the 'stator', only, it has donated it in the form of MoI rather than velocity
So you see there the connection to the current line of thought - specifically, manipulating the 'MoI' component of momentum rather than 'velocity'..
..the new question i'm asking now is this: would it be possible to repeat that interaction with
unmatched MoI's instead of equal ones, such that the 'donor' MoI
loses say 1 kg-m²-rad/s with a KE value of say ½ J (its optimal value per
KE=½mV²), while the boosted MoI
gains 1 kg-m²-rad/s for ½ J of torque * angle from the motor, yet having a
KE value in the observer FoR transposed up by whatever the initial system velocity..?
IOW, exactly the same interaction as above - equal momentum in as out - but decoupling the KE loss and gain ratio. For example, instead of pulling the masses all the way in on a matched vMoI, why not pull them partially in on a much larger vMoI - so instead of starting with 1 kg-m² of MoI turning at 1 rad/s and donating ALL of that MoI, why not begin with say 10 kg-m² of vMoI at 1 rad/s so 10 kg-m²-rad/s of momentum, then reduce it by the same 1 kg-m²-rad/s, so leaving 9 kg-m²-rad/s remaining, and whilst accelerating say a ½ kg-m² 'primary' MoI against that 1 kg-m²-rad/s of 'destroyed' momentum on the vMoI?
The TL;DR would be:
• reduce 10 kg-m²-rad/s on a 10 kg-m² MoI by 1 kg-m²-rad/s
• note KE destroyed in order to sustain that 1 kg-m²-rad/s deceleration
• note KE generated as a function of the differing MoI/V distributions
..so, primary and variable MoI's begin in equal co-rotation..
..vMoI is then reduced, while maintaining velocity by:
..torquing the primary..
..thus vMoI sheds 1 kg-m²-rad/s and x J..
..while primary gains 1 kg-m²-rad/s for y J of work, but WORTH z J of KE. Type stuff.
Maybe?