Design of the Impulsive Goodwin's Oscillator: A Case Study
Alexander Medvedev, Anton V. Proskurnikov, Zhanybai T. Zhusubaliyev
TL;DR
The paper addresses how to design an Impulsive Goodwin's Oscillator (IGO) to admit a predefined $1$-cycle by treating the continuous plant as known and the impulsive feedback parameters as design degrees of freedom, with the impulse-to-impulse map $Q$ yielding a unique positive fixed point that defines the cycle. It develops an analytical framework using the Opitz formula and divided differences to compute matrix functions, and shows that the stability of the cycle can be achieved through a static-output-feedback–like design by tuning the slopes $F'(z_0)$ and $\Phi'(z_0)$, ensuring a Schur-stable Jacobian $Q'(X)$. A concrete design algorithm is proposed to specify $(\lambda,T)$, compute the fixed point $X$ and $z_0$, shape the modulation functions, and verify stability while enforcing $F(z_0)=\lambda$ and $\Phi(z_0)=T$. A numerical example demonstrates the procedure, while bifurcation analysis reveals how the designed $1$-cycle evolves under parameter variations, including period-doubling; the work lays the groundwork for dosing applications in chemical and biomedical contexts by providing a principled method to realize robust, predefined periodic behavior.
Abstract
The impulsive Goodwin's oscillator (IGO) is a hybrid model composed of a third-order continuous linear part and a pulse-modulated feedback. This paper introduces a design problem of the IGO to admit a desired periodic solution. The dynamics of the continuous states represent the plant to be controlled, whereas the parameters of the impulsive feedback constitute design degrees of freedom. The design objective is to select the free parameters so that the IGO exhibits a stable 1-cycle with desired characteristics. The impulse-to-impulse map of the oscillator is demonstrated to always possess a positive fixed point that corresponds to the desired periodic solution; the closed-form expressions to evaluate this fixed point are provided. Necessary and sufficient conditions for orbital stability of the 1-cycle are presented in terms of the oscillator parameters and exhibit similarity to the problem of static output control. An IGO design procedure is proposed and validated by simulation. The nonlinear dynamics of the designed IGO are reviewed by means of bifurcation analysis. Applications of the design procedure to dosing problems in chemical industry and biomedicine are envisioned.
