Analog simulation of the dynamics of a van der Pol oscillator coupled to a Duffing oscillator

This paper studies with analog simulators, the dynamics of a system consisting of a van der Pol oscillator coupled to a Duffing oscillator. Amplitude-response curves are obtained in the case of internal resonance. The jump or hysteresis phenomenon is round. Various bifurcations are observed, and it is found that chaos can appear suddenly, through period-adding or through torus breakdown, The experimental results are compared with the numerical solutions.