Chromatophore Wave Kymograph

Neural Drive

Pattern

Drive amplitude 70%

Wave / flash speed 1.0×

Muscle Time Constants

Expansion τ (radial muscle contraction) 160 ms

Relaxation τ (passive elastic recoil) 650 ms

Pigment Layers

Yellow Red-orange Brown

Live Readout

Strip-average surface color
#4fd1c5

Mean sac coverage

Organs fully expanded

Expand : relax ratio

1 : 4.1

Pattern phase

0.0 s

How it works

This is a 2D-native reduction of the same chromatophore neural-drive model, not a flattened camera view of the 3D skin patch. The traveling-wave / flicker / flash target signal in the source model depends only on position along one axis (x) and time — the second spatial axis carries no information, only cosmetic per-organ jitter. So the physics is captured exactly by a 1D chain of organs, and the resulting time series is drawn as a kymograph: a space-time image where the horizontal axis is position across the skin strip, the vertical axis scrolls downward through time, and pixel color is the same layered pigment composite the source uses. A traveling wave becomes a visible diagonal stripe whose slope is the wave speed; a synchronized flash becomes a horizontal band; flicker becomes spatial noise with no coherent slope.

Beneath it, a phase-portrait plot tracks one representative organ's coverage fraction e against its instantaneous target, tracing the same asymmetric ODE as the source:

de/dt = (target − e) / τ_expand   if target > e   (fast: muscle contraction)
de/dt = (target − e) / τ_relax    if target ≤ e   (slow: passive elastic recoil)
radius(e) = r_max · √e             (Area ∝ e)

Because expansion is much faster than relaxation, the trajectory in the (target, e) plane sits close to the diagonal on the way up but lags well behind it on the way down — a visible hysteresis loop that is exactly what makes real octopus skin flash on instantly and fade out slowly.

Yellow chromatophores Red-orange chromatophores Brown/black chromatophores Iridophore base layer