Duffing Oscillator Chaos

x'' + δx' + αx + βx³ = γcos(ωt) — Poincaré section, phase portrait, bifurcation

Phase
Poincaré
Bifurc.

Parameters

Double-well Duffing: α<0, β>0 gives two stable equilibria ±√(−α/β).

Chaos: at γ≈0.3, ω≈1.2 → strange attractor with fractal structure.

Poincaré section: sample (x, ẋ) once per forcing period — periodic orbit → finite dots, chaos → fractal cloud.