Figure 9.

Typical examples showing the performance of the embedded quadratic limit cycle with external noise. The white noises, δO₁ (t) and δO₂ (t), in the range of ϵ (δO_1,2 (t) ∈[−ϵ, ϵ]) are added to the motor outputs during t = 6000 − 7000 timesteps. (A) Typical trajectories of O₁ (t) and O₂ (t) compared with the target time series. The upper, middle, and lower figures show the case with ϵ = 10.0, 5.0, and 1.0, respectively. (B) The corresponding plots in the O₁ (t) - O₂ (t) (x₁ (t) - x₂ (t)) plane. For each noise level, the trajectories are overlaid from 5000 to 30,000 timesteps.