Multiscroll attractor

Strange attractor connected by two 2-dimensional rings
Double-scroll attractor from a simulation

In the mathematics of dynamical systems, the double-scroll attractor (sometimes known as Chua's attractor) is a strange attractor observed from a physical electronic chaotic circuit (generally, Chua's circuit) with a single nonlinear resistor (see Chua's diode). The double-scroll system is often described by a system of three nonlinear ordinary differential equations and a 3-segment piecewise-linear equation (see Chua's equations). This makes the system easily simulated numerically and easily manifested physically due to Chua's circuits' simple design.

Using a Chua's circuit, this shape is viewed on an oscilloscope using the X, Y, and Z output signals of the circuit. This chaotic attractor is known as the double scroll because of its shape in three-dimensional space, which is similar to two saturn-like rings connected by swirling lines.

The attractor was first observed in simulations, then realized physically after Leon Chua invented the autonomous chaotic circuit which became known as Chua's circuit.[1] The double-scroll attractor from the Chua circuit was rigorously proven to be chaotic[2] through a number of Poincaré return maps of the attractor explicitly derived by way of compositions of the eigenvectors of the 3-dimensional state space.[3]

Numerical analysis of the double-scroll attractor has shown that its geometrical structure is made up of an infinite number of fractal-like layers. Each cross section appears to be a fractal at all scales.[4] Recently, there has also been reported the discovery of hidden attractors within the double scroll.[5]

In 1999 Guanrong Chen (陈关荣) and Ueta proposed another double scroll chaotic attractor, called the Chen system or Chen attractor.[6][7]

Chen attractor

The Chen system is defined as follows[7]

d x ( t ) d t = a ( y ( t ) x ( t ) ) {\displaystyle {\frac {dx(t)}{dt}}=a(y(t)-x(t))}

d y ( t ) d t = ( c a ) x ( t ) x ( t ) z ( t ) + c y ( t ) {\displaystyle {\frac {dy(t)}{dt}}=(c-a)x(t)-x(t)z(t)+cy(t)}

d z ( t ) d t = x ( t ) y ( t ) b z ( t ) {\displaystyle {\frac {dz(t)}{dt}}=x(t)y(t)-bz(t)}

Plots of Chen attractor can be obtained with the Runge-Kutta method:[8]

parameters: a = 40, c = 28, b = 3

initial conditions: x(0) = -0.1, y(0) = 0.5, z(0) = -0.6

Other attractors

Multiscroll attractors also called n-scroll attractor include the Lu Chen attractor, the modified Chen chaotic attractor, PWL Duffing attractor, Rabinovich Fabrikant attractor, modified Chua chaotic attractor, that is, multiple scrolls in a single attractor.[9]

Lu Chen attractor

Lu Chen Attractor

An extended Chen system with multiscroll was proposed by Jinhu Lu (吕金虎) and Guanrong Chen[9]

Lu Chen system equation

d x ( t ) d t = a ( y ( t ) x ( t ) ) {\displaystyle {\frac {dx(t)}{dt}}=a(y(t)-x(t))}

d y ( t ) d t = x ( t ) x ( t ) z ( t ) + c y ( t ) + u {\displaystyle {\frac {dy(t)}{dt}}=x(t)-x(t)z(t)+cy(t)+u}

d z ( t ) d t = x ( t ) y ( t ) b z ( t ) {\displaystyle {\frac {dz(t)}{dt}}=x(t)y(t)-bz(t)}

parameters:a = 36, c = 20, b = 3, u = -15.15

initial conditions:x(0) = .1, y(0) = .3, z(0) = -.6

Modified Lu Chen attractor

Lu Chen Attractor modified

System equations:[9]

d x ( t ) d t = a ( y ( t ) x ( t ) ) , {\displaystyle {\frac {dx(t)}{dt}}=a(y(t)-x(t)),}

d y ( t ) d t = ( c a ) x ( t ) x ( t ) f + c y ( t ) , {\displaystyle {\frac {dy(t)}{dt}}=(c-a)x(t)-x(t)f+cy(t),}

d z ( t ) d t = x ( t ) y ( t ) b z ( t ) {\displaystyle {\frac {dz(t)}{dt}}=x(t)y(t)-bz(t)}

In which

f = d 0 z ( t ) + d 1 z ( t τ ) d 2 sin ( z ( t τ ) ) {\displaystyle f=d0z(t)+d1z(t-\tau )-d2\sin(z(t-\tau ))}

params := a = 35, c = 28, b = 3, d0 = 1, d1 = 1, d2 = -20..20, tau = .2

initv := x(0) = 1, y(0) = 1, z(0) = 14

Modified Chua chaotic attractor

Chua Attractor

In 2001, Tang et al. proposed a modified Chua chaotic system[10]

d x ( t ) d t = α ( y ( t ) h ) {\displaystyle {\frac {dx(t)}{dt}}=\alpha (y(t)-h)}

d y ( t ) d t = x ( t ) y ( t ) + z ( t ) {\displaystyle {\frac {dy(t)}{dt}}=x(t)-y(t)+z(t)}

d z ( t ) d t = β y ( t ) {\displaystyle {\frac {dz(t)}{dt}}=-\beta y(t)}

In which

h := b sin ( π x ( t ) 2 a + d ) {\displaystyle h:=-b\sin \left({\frac {\pi x(t)}{2a}}+d\right)}

params := alpha = 10.82, beta = 14.286, a = 1.3, b = .11, c = 7, d = 0

initv := x(0) = 1, y(0) = 1, z(0) = 0

PWL Duffing chaotic attractor

PWL Duffing Attractor

Aziz Alaoui investigated PWL Duffing equation in 2000:[11]

PWL Duffing system:

d x ( t ) d t = y ( t ) {\displaystyle {\frac {dx(t)}{dt}}=y(t)}

d y ( t ) d t = m 1 x ( t ) ( 1 / 2 ( m 0 m 1 ) ) ( | x ( t ) + 1 | | x ( t ) 1 | ) e y ( t ) + γ cos ( ω t ) {\displaystyle {\frac {dy(t)}{dt}}=-m_{1}x(t)-(1/2(m_{0}-m_{1}))(|x(t)+1|-|x(t)-1|)-ey(t)+\gamma \cos(\omega t)}

params := e = .25, gamma = .14+(1/20)i, m0 = -0.845e-1, m1 = .66, omega = 1; c := (.14+(1/20)i),i=-25...25;

initv := x(0) = 0, y(0) = 0;

Modified Lorenz chaotic system

Lorenz system modified

Miranda & Stone proposed a modified Lorenz system:[12]

d x ( t ) d t = 1 / 3 ( ( a + 1 ) x ( t ) + a c + z ( t ) y ( t ) ) + ( ( 1 a ) ( x ( t ) 2 y ( t ) 2 ) + ( 2 ( a + c z ( t ) ) ) x ( t ) y ( t ) ) {\displaystyle {\frac {dx(t)}{dt}}=1/3*(-(a+1)x(t)+a-c+z(t)y(t))+((1-a)(x(t)^{2}-y(t)^{2})+(2(a+c-z(t)))x(t)y(t))} 1 3 x ( t ) 2 + y ( t ) 2 {\displaystyle {\frac {1}{3{\sqrt {x(t)^{2}+y(t)^{2}}}}}}

d y ( t ) d t = 1 / 3 ( ( c a z ( t ) ) x ( t ) ( a + 1 ) y ( t ) ) + ( ( 2 ( a 1 ) ) x ( t ) y ( t ) + ( a + c z ( t ) ) ( x ( t ) 2 y ( t ) 2 ) ) {\displaystyle {\frac {dy(t)}{dt}}=1/3((c-a-z(t))x(t)-(a+1)y(t))+((2(a-1))x(t)y(t)+(a+c-z(t))(x(t)^{2}-y(t)^{2}))} 1 3 x ( t ) 2 + y ( t ) 2 {\displaystyle {\frac {1}{3{\sqrt {x(t)^{2}+y(t)^{2}}}}}}

d z ( t ) d t = 1 / 2 ( 3 x ( t ) 2 y ( t ) y ( t ) 3 ) b z ( t ) {\displaystyle {\frac {dz(t)}{dt}}=1/2(3x(t)^{2}y(t)-y(t)^{3})-bz(t)}

parameters: a = 10, b = 8/3, c = 137/5;

initial conditions: x(0) = -8, y(0) = 4, z(0) = 10

Gallery

  • Chen attractor
    Chen attractor
  • a = 35, c = 27, b = 2.8,x(0) = -.1, y(0) = .3, z(0) = -.6
    parameters a = 35, c = 27, b = 2.8,x(0) = -.1, y(0) = .3, z(0) = -.6
  • Lu Chen attractor
    Lu Chen attractor
  • Maple plot of N scroll attractor based on Chen with sine and tau
    Maple plot of N scroll attractor based on Chen with sine and tau
  • 9 scroll modified Chua chaotic attractor
    9 scroll modified Chua chaotic attractor
  • xy plot of 9 scroll modified Chua chaotic attractor
    xy plot of 9 scroll modified Chua chaotic attractor
  • PWL Duffing chaotic attractor xy plot
    PWL Duffing chaotic attractor xy plot
  • PWL Duffing chaotic attractor plot
    PWL Duffing chaotic attractor plot
  • modified Lorenz attractor
    modified Lorenz attractor
  • Rabinovich Fabrikant attractor xy plot
    Rabinovich Fabrikant attractor xy plot

References

  1. ^ Matsumoto, Takashi (December 1984). "A Chaotic Attractor from Chua's Circuit" (PDF). IEEE Transactions on Circuits and Systems. CAS-31 (12). IEEE: 1055–1058. doi:10.1109/TCS.1984.1085459.
  2. ^ Chua, Leon; Motomasa Komoru; Takashi Matsumoto (November 1986). "The Double-Scroll Family" (PDF). IEEE Transactions on Circuits and Systems. CAS-33 (11).
  3. ^ Chua, Leon (2007). "Chua circuits". Scholarpedia. 2 (10): 1488. Bibcode:2007SchpJ...2.1488C. doi:10.4249/scholarpedia.1488.
  4. ^ Chua, Leon (2007). "Fractal Geometry of the Double-Scroll Attractor". Scholarpedia. 2 (10): 1488. Bibcode:2007SchpJ...2.1488C. doi:10.4249/scholarpedia.1488.
  5. ^ Leonov G.A.; Vagaitsev V.I.; Kuznetsov N.V. (2011). "Localization of hidden Chua's attractors" (PDF). Physics Letters A. 375 (23): 2230–2233. Bibcode:2011PhLA..375.2230L. doi:10.1016/j.physleta.2011.04.037.
  6. ^ Chen G., Ueta T. Yet another chaotic attractor. Journal of Bifurcation and Chaos, 1999 9:1465.
  7. ^ a b CHEN, GUANRONG; UETA, TETSUSHI (July 1999). "Yet Another Chaotic Attractor". International Journal of Bifurcation and Chaos. 09 (7): 1465–1466. Bibcode:1999IJBC....9.1465C. doi:10.1142/s0218127499001024. ISSN 0218-1274.
  8. ^ 阎振亚著 《复杂非线性波的构造性理论及其应用》第17页 SCIENCEP 2007年
  9. ^ a b c Chen, Guanrong; Jinhu Lu (2006). "Generating Multiscroll Chaotic Attractors: Theories, Methods and Applications" (PDF). International Journal of Bifurcation and Chaos. 16 (4): 775–858. Bibcode:2006IJBC...16..775L. doi:10.1142/s0218127406015179. Retrieved 2012-02-16.
  10. ^ Chen, Guanrong; Jinhu Lu (2006). "Generating Multiscroll Chaotic Attractors: Theories, Methods and Applications" (PDF). International Journal of Bifurcation and Chaos. 16 (4): 793–794. Bibcode:2006IJBC...16..775L. CiteSeerX 10.1.1.927.4478. doi:10.1142/s0218127406015179. Retrieved 2012-02-16.
  11. ^ J. Lu, G. Chen p. 837
  12. ^ J.Liu and G Chen p834

External links

  • The double-scroll attractor and Chua's circuit
  • Lozi, R.; Pchelintsev, A.N. (2015). "A new reliable numerical method for computing chaotic solutions of dynamical systems: the Chen attractor case". International Journal of Bifurcation and Chaos. 25 (13): 1550187–1550412. Bibcode:2015IJBC...2550187L. doi:10.1142/S0218127415501874. S2CID 12339358.
  • v
  • t
  • e
Chaos theory
Concepts
Core
Theorems
Conus textile shell


Circle map with black Arnold tongues
Theoretical
branchesChaotic
maps (list)
Discrete
Continuous
Physical
systemsChaos
theoristsRelated
articles