Numerical Treatment of Singularity in Hydraulic Circuits Using Singular Perturbation Theory

Numerical Integration Scheme Using Singular Perturbation Method

Some multi degree-of-freedom dynamical systems exhibit a response that contain fast and slow variables. An example of such systems is a multibody system with rigid and deformable bodies. Standard numerical integration of the resultant equations of motion must adjust the time step according to the frequency of the fastest variable. As a result, the computation time is sacrificed. The singular pe...

Singular perturbation theory

When we apply the steady-state approximation (SSA) in chemical kinetics, we typically argue that some of the intermediates are highly reactive, so that they are removed as fast as they are made. We then set the corresponding rates of change to zero. What we are saying is not that these rates are identically zero, of course, but that they are much smaller than the other rates of reaction. The st...

Geometric Singular Perturbation Theory

Singular Perturbation Theory in Output Feedback Control of Pure-Feedback Systems

This paper studies output feedback control of pure-feedback systems with immeasurable states and completely non-affine property. Since availability of all the states is usually impossible in the actual process, we assume that just the system output is measurable and the system states are not available. First, to estimate the immeasurable states a state observer is designed. Relatively fewer res...

Application of Singular Perturbation Theory to Hydraulic Servo Drives - System Analysis and Control Design

This paper describes the system analysis and control design of an electrohydraulic servo-drive using a nonlinear composite feedback control approach based on singular perturbation theory (Kokotovic, Khalil & O’Reilly 1986). A comparison with linear output feedback (P-control) and linear state feedback (LQRdesign) shows the bene¿ts of the proposed method. The nonlinear control design features fe...