Recent advances on recursive filtering and sliding mode design for networked nonlinear stochastic systems: A survey

Copyright © 2013 Jun Hu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Some recent advances on the recursive filtering and sliding mode design problems for nonlinear stochastic systems with network-induced phenomena are surveyed. The network-induced phenomena under consideration mainly include missing measurements, fading measurements, signal quantization, probabilistic sensor delays, sensor saturations, randomly occurring nonlinearities, and randomly occurring uncertainties. With respect to these network-induced phenomena, the developments on filtering and sliding mode design problems are systematically reviewed. In particular, concerning the network-induced phenomena, some recent results on the recursive filtering for time-varying nonlinear stochastic systems and sliding mode design for time-invariant nonlinear stochastic systems are given, respectively. Finally, conclusions are proposed and some potential future research works are pointed out.This work was supported in part by the National Natural Science Foundation of China under Grant nos. 61134009, 61329301, 61333012, 61374127 and 11301118, the Engineering and Physical Sciences Research Council (EPSRC) of the UK under Grant no. GR/S27658/01, the Royal Society of the UK, and the Alexander von Humboldt Foundation of Germany

Robust passivity-based continuous sliding-mode control for under-actuated nonlinear wing sections

The stability of an under-actuated nonlinear aeroelastic wing section is addressed using a robust passivity-based continuous sliding-mode control approach. The controller is shown to be capable of stabilising the system in the presence of large matched and mismatched uncertainties and large input disturbance. It is demonstrated in theory that within known bounds on the input disturbance and nonlinearity uncertainty, the controller is able to stabilise the system globally. A numerical example, based on the Texas A&M University experimental rig, is used to demonstrate the stabilisation of the system with a fully-developed limit cycle oscillation and a flap deflection limited to 20 degrees. This is of practical interest because it shows that the system is at least stabilised locally, whereas global stability is a concept limited to theoretical studies and is impossible to demonstrate in practice

Decentralized sliding mode control and estimation for large-scale systems

This thesis concerns the development of an approach of decentralised robust control and estimation for large scale systems (LSSs) using robust sliding mode control (SMC) and sliding mode observers (SMO) theory based on a linear matrix inequality (LMI) approach. A complete theory of decentralized first order sliding mode theory is developed. The main developments proposed in this thesis are: The novel development of an LMI approach to decentralized state feedback SMC. The proposed strategy has good ability in combination with other robust methods to fulfill specific performance and robustness requirements. The development of output based SMC for large scale systems (LSSs). Three types of novel decentralized output feedback SMC methods have been developed using LMI design tools. In contrast to more conventional approaches to SMC design the use of some complicated transformations have been obviated. A decentralized approach to SMO theory has been developed focused on the Walcott-Żak SMO combined with LMI tools. A derivation for bounds applicable to the estimation error for decentralized systems has been given that involves unknown subsystem interactions and modeling uncertainty. Strategies for both actuator and sensor fault estimation using decentralized SMO are discussed.The thesis also provides a case study of the SMC and SMO concepts applied to a non-linear annealing furnace system modelderived from a distributed parameter (partial differential equation) thermal system. The study commences with a lumped system decentralised representation of the furnace derived from the partial differential equations. The SMO and SMC methods derived in the thesis are applied to this lumped parameter furnace model. Results are given demonstrating the validity of the methods proposed and showing a good potential for a valuable practical implementation of fault tolerant control based on furnace temperature sensor faults

Extensions of Retrospective Cost Adaptive Control: Nonsquare Plants, and Robustness Modifications.

Controllers that have adjustable parameters, and an update law for adjusting these parameters, are called ``adaptive controllers''. Adaptive controllers typically entail assumptions about the dynamic order, relative degree or transmission zeros of the system, and may not be applicable to systems that are not positive real, passive, or minimum phase. In 1980s, the fragility of adaptive controllers to violations in these assumptions has been demonstrated through various counterexamples. This motivated the development of robustness modifications for adaptive controllers, which is the main goal of this dissertation. In this dissertation, we focus on retrospective cost adaptive control (RCAC), which is a direct, digital adaptive control algorithm. RCAC is applicable to MIMO, nonminimum-phase (NMP) systems, but it assumes that the NMP zeros of the plant, if any, are known. The main contribution of this work includes theory and analysis for retrospective cost adaptive control of nonsquare systems and development of a modified, robust RCAC update law for maintaining stability and convergence in the presence of unmodeled NMP zeros.PHDAerospace EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/97926/1/dogan_1.pd

ABS design and active suspension control based on HOSM

This paper tackles the control of a brake assisted with an active suspension. The goal of the paper is ensure an effective braking process improving the vehicle safety in adverse driving conditions. To address this, the wheel slip ratio is kept to a desired value reducing the effective braking distance by designing of a robust tracking controller based on high order sliding modes algorithms, imposing the anti-lock brake system feature. On the other hand, the active suspension problem is carried with a nested backward sliding surface design. The purpose of this control is to improve the driving comfort. To this aim, the designed controller compensate the effects of the unmatched perturbation coming from the road. This controller exploits a high order sliding modes observer, which guarantees theoretically exact state and perturbation estimation. In both cases, a continuous control action drives the state trajectories to the designed sliding manifolds and keeps them there in spite of the matched and unmatched perturbations. The feasibility of the proposed scheme has been exposed via simulations.Consejo Nacional de Ciencia y TecnologíaUniversity of Bordeau

Diseño de controladores continuos convergentes por un tiempo fijo para sistemas dinámicos con incertidumbre

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