Modeling & simulation of nonlinear dynamics of periodic cardiac pacemaker using bond graph techniques

A lot of research has been done targeting differential equations and state space of cardiac pacemakers while very few authors have discussed the circuit of the van der Pol oscillator. This paper aims at developing the van der Pol oscillator using RLC circuits with non-linear resistance. This was done by representing the modified forced van der pol oscillator with non-linear resistance using piecewise S curve obtained through an operational amplifier. The state space has been obtained, using 20-Sim software, followed by its differential equation. The phase portrait of the modified forced van der Pol oscillator has also been developed. In this paper, the behavior of real cardiac pacemaker has been reproduced in time domain and a comparison of the real and the reproduced cardiac pacemaker has been made.