Positive and Negative Feedback

We construct a minimal dynamic system with both positive and negative feedback. We'll have two state variables, x and y, and render the phase trajectory as a dot. github

We can interpret x*g and y*g as velocity that accumulates in the positions x and y. The velocity of x is proportional to the position y and vice versa.

We could derive velocity from acceleration caused by magnetic attraction. If everything were balanced just right then we would get the same motion. If anything were off then we get elliptical motion or worse, if we add a few more magnets we get chaos.

The inverse square attraction gets higher as the chance approach gets closer and that "slingshots" the velocity high enough for our dot to move out of view.

This is due to sampling error in my numerical integration of position and velocity from rapidly changing acceleration.

See Magnetic Ribbon for a version dating back to 1996.

A pole-zero plot shows the location in the complex plane of the poles and zeros of the transfer function of a dynamic system, such as a controller, compensator, sensor, equalizer, filter, or communications channel. wikipeda mit

This looks even better in 3d. Crazy. Maybe with some refactoring I can get a bunch of dots flying around.

We try a hierarchy of orbits around the sun, earth, moon and lunar orbiter trailing a long string. doc doc

Note the string is in world coordinates with the sun but lead by orbiter coordinates transformed to world. doc

I need to try the cylindrical attractor as demonstrated on the space station.