Robust control techniques for stabilization of twin rotor mimo system trms in the non linear regime

Abstract

With the advent of robust control techniques and state-of-the-art mathematical newlinesolvers, it is now possible to solve robust control problems of many Multi Input Multi newlineOutput (MIMO) systems in affordable time. In this research work, the Twin Rotor newlineMIMO System (TRMS) is considered for experimentation that invariably exhibits one or newlinemore of the typical attributes, viz. RHP zero dynamics, cross coupling, model newlineuncertainties, sensitivities to exogenous inputs, singularities, and resonances. All these newlineattributes together find this system (TRMS) very challenging from control prospective. newlineClassical linear control of TRMS has certain difficulties in the context of computational newlineintricacies, especially in the MIMO domain. It is also stated that classical feedback newlinelinearization techniques are not fit for system with non-minimum phase dynamics. In this newlinework, it is proposed to design a H2/Hand#8734; controller from the nominal Linear Time Invariant newline(LTI) model of the system, in order to achieve internal stability in tracking and newlineregulation. Thus, this research work comprises of two stages of control system design, newlineviz. 1) modelling of the physical TRMS, and 2) designing the controller and testing on newlinethe physical plant. Controllers are validated experimentally on TRMS 1) by computer newlinesimulation, and 2) in real time. newlineModelling is generally the first step in the process of control systems design. newlineSeveral efforts have been made by researchers in past to develop nominal LTI models for newlineTRMS. So far, the preferred test inputs for system identification of TRMS are square newlinewaves, sine waves, white noise or binary inputs as reported in former works. In this newlineresearch work Chirp inputs are suggested as most suitable test signals for input output newlinetest of TRMS. The LTI models are developed by two different methods as required by newlinethe present research problem, explained next. newline