Orrery 5: Randomness, Recoverable

Stepping away from the computer as always produces new ideas. While running, I realised that I could dramatically improve my figure-yield by changing the way I randomise the orbital characteristics: instead of just multiplying each of the six parameters by a random value (between, say 0.999 and 1.001) each time, I can precalculate a random walk of values for each parameter which is guaranteed to return to 0 by:

  • generating a randomised set half of [total iterations] long;
  • copying it & multiplying each element in the copied set by -1;
  • shuffling the full-length set.

C. 50,000 random values later, done! Works well, and allows me to explore some higher-randomness spaces with reasonable yields (I still don't get 100% yield: not sure if it's accumulated floating-point errors or some other issue). 

Five rows in the figures below, with descending mutation values: from 0.005 in the first row to 0.001 in the last. Interesting to see how somewhere between 0.003 and 0.002 it becomes "rational".


Orrery 4: Only The Fit Survive

Extending my exploration of randomness. Reducing the mutation values to two-one-thousandths of their previous values yields almost perfect figures, but nine out of ten fail to reconnect at the end of the orbit. By comparing moonlet positions at start and end and writing out only those where the absolute x + y delta is < 2 pixels, I can render out about three "successful" slightly-mutated figures per minute.


Orrery 3: Things Fall Apart

So far the only things I've varied have been orbital distances and speeds. What if I let orbital distances vary by as much as 1% per frame? (Images open in lightbox)

It's hard to not feel compassion for these figures: you feel their earnest desire to do the right thing. Ordinarily a computer is a perfect executor of your instructions: the insertion of randomness seems to also insert some humanity, some fallibility.

Orrery 2

The Orrery project is a kind of playground for exploring parametric variation within a very tight set of variables. I'm deliberately restricting myself to a small subset of possible variations using a single three-body system:

  • C orbits B between 2 and 6 times per orbit of B, in either prograde or retrograde direction, at a distance of 10 to 25 units;
  • B orbits A between 3 and 12 times per single orbit of A, in either prograde or retrograde direction, at a distance of 25 to 50 units;
  • "Planets" or "radii" or both may be shown.

Even within the small set of variables there are millions of combinations, an aesthetic landscape which we can explore. It's challenging to apprehend even a thousand variations. Different values generate different associations: some are like etchings of microscopic diatoms or pollen grains: some are stained-glass windows; some are "French" in some way I can't quite understand, others are reminiscent of Celtic patterns.

Complexity is another dimension, easily accessible just by looking at PNG-compressed file size. Twelve examples from a random set of 1,000: the four largest, four in the middle, and the four smallest files: click thumbnails to open larger versions.


Orrery

Ongoing work prompted by the solar eclipse in Husavik on the 20th of March. Three-body system with orbital periods defined as a number of frames with integer multipliers (e.g. 2400/600/200). This is the beginning: it will get more complex from here on.