A second order sliding mode control algorithm is presented for robust control of the liquid level in a pair of interconnected tanks. The controller is implemented on a laboratory rig. The implementation results show robustness to parameter variations such as tank area, the admittance coefficients of various pipes, leakage in the tanks and uncertainty in the pump dynamics. The potential of secon...

IP protocol overheads are large and need to be compressed when used in UMTS to save radio resources. A robust header compression scheme (ROHC) has been proposed to provide high compression efficiency and high robustness. We study the performance of ROHC in the paper and investigate how to adjust some compression parameters that are recommended as implementation-dependent according to the ROHC s...

An application is presented of1 synthesis to the robust control of a large  exible space structure experimental testbed called Daisy. A perturbed left-coprime factorization of Daisy’s dynamics is used to capture the uncertainty in the modes. Designs of the 1 synthesis controller based on left-coprime factorizations of 46th-order collocated and noncollocatedmodels of Daisy are presented togethe...

We develop control laws for the pendular motion of a spinning tethered satellite system. The control laws are developed using a simplified system model that contains unknown disturbance terms that account for unmodeled dynamics in the simplified model. Principles of sliding mode and adaptive nonlinear control design are used to develop control laws that drive the pendular motion to a desired re...

We propose an optimal control approach to robust control design. Our goal is to design a state feedback to stabilize a system under uncertainty. We translate this robust control problem into an optimal control problem of minimizing a cost. Because the uncertainty bound is reeected in the cost, the solution to the optimal control problem is a solution to the robust control problem. Our approach ...

Decentralized robust controller design problem for large-scale interconnected systems which involve uncertainties in the system matrices and uncertain time-delays is considered. An error bound, which accounts for the neglected interactions between the subsystem models and uncertainties in the interactions, in the subsystem models, and in the time delays is first derived using overlapping decomp...

Observer design is classically considered as a dual problem to state feedback. But very few results address this issue in the context of uncertain system, at least in comparison of robust state-feedback design. This fact has motivated us for studying robust design of both state-feedback gains and Luemberger-like observers and we in particular show that in case of uncertain systems these two des...

Moat realistic control problems involve both some type of time-domain constraints and model uncertainty. However, there presently exist few design methods capable of simultaneously addressing both issues. We recently proposed to address this class of problem by using a "constrained robustness measure", generated by a constraint-set induced operator norm, to assess the stability ptoperties of a ...

In this paper, we evaluate the stability margin of a Fiat Dedra engine model to explore possible applications of theoretical achievements in the parametric approach to robust control problems. The study is based on two versions of the model with uncertainties. One is the original model, which has a multilinear characteristic polynomial, while the other is an affine-linearized model which is obt...

A robust controller is designed for a system consisting of two carts coupled by a spring. Special attention is given to the input saturations. This problem was posed within a benchmark collection for robust control techniques and treated for example at the 1992 ACC. μ analysis and simulation studies illustrate our design.