  Model-free reconstruction of the bifurcation diagrams of Chua's circuits by
the technique of parameter-aware reservoir computing is investigated. We
demonstrate that: (1) reservoir computer can be utilized as a noise filter to
recover the system trajectory from noisy signals; (2) for a single Chua
circuit, the machine trained by the noisy time series measured at several
sampling states is capable of reconstructing the whole bifurcation diagram of
the circuit with a high precision; (3) for two coupled chaotic Chua circuits of
mismatched parameters, the machine trained by the noisy time series measured at
several coupling strengths is able to anticipate the variation of the
synchronization degree of the coupled circuits with respect to the coupling
strength over a wide range. The studies verify the capability of the technique
of parameter-aware reservoir computing in learning the dynamics of chaotic
circuits from noisy signals, signifying the potential application of this
technique in reconstructing the bifurcation diagram of real-world chaotic
systems.
