GenesioTesi¶
Systems / ODEs / Chaotic attractors
A canonical jerk control system whose single quadratic nonlinearity, analysed by harmonic balance, produces a Shilnikov strange attractor.
Definition¶
\[
\begin{aligned}
\dot{x} &= y \\
\dot{y} &= z \\
\dot{z} &= - a z - b y - c x + x^{2}
\end{aligned}
\]
Parameters¶
| Symbol | Default | Role |
|---|---|---|
a |
0.44 |
acceleration feedback gain |
b |
1.1 |
velocity feedback gain |
c |
1 |
position feedback gain |
State variables: x, y, z
Properties¶
Lyapunov spectrum
TODO — lyapunov_spectrum failed: AttributeError
Kaplan–Yorke dimension
TODO — requires a numeric Lyapunov spectrum
Divergence ∇·f
$\nabla\!\cdot f = - a$
constant
constant
Equilibria
2 equilibria
0 stable · 2 unstable
0 stable · 2 unstable
Use it in TSDynamics¶
import tsdynamics as ts
system = ts.systems.GenesioTesi()
traj = system.run(final_time=100.0, dt=0.01)
ts.plot(traj)
spectrum = ts.analysis.lyapunov_spectrum(system)
ts.analysis.kaplan_yorke_dimension(spectrum)
Reference¶
Genesio & Tesi (1992), Automatica 28, 531-548
doi:10.1016/0005-1098(92)90177-h